User’s Guide Tenth Edition (February 2008) Part Number: T2558-96073
© Copyright 2008 Hewlett-Packard Development Company, L.P. Hewlett-Packard Company makes no warranty of any kind with regard to this material, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. Hewlett-Packard shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this material.
Table of Contents Chapter 1: Introduction ...........................................................................................................1-1 Intended audience .................................................................................................................... 1-1 Conventions used in this guide ............................................................................................... 1-1 Resources ...............................................................................
Saving a workspace ........................................................................................................................................................................ 4-5 Opening a workspace .................................................................................................................................................................... 4-6 Failover Control Center ..........................................................................................................
Understanding the Source Connection Resource ..............................................................10-6 ..................................................................................................................................................10-6 Chapter 11: Protecting Data Across a NAT or Firewall ...................................................... 11-1 Verifying the Storage Mirroring port settings .....................................................................
Queuing Storage Mirroring data ........................................................................................14-22 Understanding queuing ......................................................................................................................................................................14-22 Configuring queuing ...........................................................................................................................................................................
19-1 Log Files ...................................................................................................................................19-2 Viewing the log files .............................................................................................................................................................................. 19-3 Using LogViewer ...............................................................................................................................................
1 X Introduction Introduction Intended audience The intended audience for the HP StorageWorks Storage Mirroring® User’s Guide is network administrators with expertise in Microsoft® Windows®. The network administrator should be responsible for setup and maintenance of the network and should have working experience installing, configuring, and maintaining network applications.
2 X Storage Mirroring Overview Storage Mirroring Overview HP StorageWorks Storage Mirroring is a real-time data replication and failover software product. Storage Mirroring augments your existing data protection strategy by reducing downtime and data loss, and it provides these services with minimal impact on existing network and communication resources.
Storage Mirroring operations Storage Mirroring performs four basic types of operations.
Replication Replication is the real-time transmission of file changes. Unlike other related technologies, which are based on a disk driver or a specific application, the Storage Mirroring replication process operates at the file system level and is able to track file changes independently from the file’s related application. In terms of network resources and time, replicating changes is a more efficient method of maintaining a real-time copy of data than copying an entire file that has changed.
Failure monitoring and failover Failover is the process in which a target stands in for a failed source. As a result, user and application requests that are directed to the failed source are routed to the target. Storage Mirroring monitors the source status by tracking network requests and responses exchanged between the source and target. When a monitored source misses a user-defined number of requests, Storage Mirroring assumes that the server has failed.
Restoration Restoration provides an easy method for copying replicated data from the target back to its original location on the source. The process only requires you to select the source, target, and the appropriate replication set. There is no need to select files or to remember where the data came from on the source since that information is maintained by Storage Mirroring.
Storage Mirroring add-ons and features Special Storage Mirroring add-ons and features build on the core Storage Mirroring techology. For example, the Server Recovery Option add-on provides disaster recovery protection for an entire server. The Storage Mirroring Reporting Center feature provides reporting and analysis tools for your entire Storage Mirroring environment. The difference between add-ons and features is mainly licensing. You will need a separate activation code for Storage Mirroring add-ons.
Full-Server Failover Option The Storage Mirroring Full-Server Failover Option feature provides high availability for an entire server, including the system state, which is the server’s configured operating system and applications. Using Full-Server Failover Manager, you identify your source, which is the server you want to protect, and your target, which is the server that will stand-in for the source in the event the source fails.
Storage Mirroring Reporting Center The Storage Mirroring Reporting Center feature is a centralized reporting and analysis solution that offers detailed, custom analysis and reports of your entire Storage Mirroring environment. It has a server component that provides data collection and a monitoring engine, and there is a client component that provides the configuration, graphical reporting, and monitoring capabilities.
Sample configurations Storage Mirroring is an exceptionally flexible product that can be used in a wide variety of network configurations. To implement Storage Mirroring effectively, it is important to understand the possible configuration options and their relative benefits. Storage Mirroring configuration options can be used independently or in varying combinations. NOTE: The Storage Mirroring replication and failover features have different server requirements.
One-to-one, active/active Data from first source Data from second source Source and Target (Active) Target and Source (Active) Description Each server acts as both a source and target actively replicating data to each other. Applications This configuration is appropriate for failover and critical data backup. This configuration is more cost-effective than the Active/Standby configuration because there is no need to buy a dedicated target server for each source.
Many-to-one Source Source Target Source Description Many source servers are protected by one target server. Application This configuration is appropriate for offsite disaster recovery. This is also an excellent choice for providing centralized tape backup because it spreads the cost of one target server among many source servers. Considerations The target server must be carefully managed. It must have enough disk space and RAM to support replication from all of the source systems.
One-to-many Target Source Target Target Description One source server sends data to multiple target servers. The target servers may or may not be accessible by one another. Applications This configuration provides offsite disaster recovery, redundant backups, and data distribution. For example, this configuration can replicate all data to a local target server and separately replicate a subset of the mission-critical data to an offsite disaster recovery server.
Chained Source Target and Source Target Description The source servers sends replicated data to a target server, which acts as a source server and sends data to a final target server, which is often offsite. Applications This is a convenient approach for integrating local high availability with offsite disaster recovery. This configuration moves the processing burden of WAN communications from the source server to the target/source server.
Single server C:\Data Replication set data D:\Data Copy of replication set data on specified target path Source and Target Description Source and target Storage Mirroring components are loaded on the same server allowing data to be replicated from one location to another on the same volume or to a separate volume on the same server. These could be locally attached SCSI drives or Fibre Channel based SAN devices.
Virtual systems Guest Guest Host Host Source Target Virtual to virtual configuration Source Guest Guest Guest Host Source Target Source Physical to virtual configuration Description Source and/or target Storage Mirroring components are loaded on the guest operating system allowing data to be replicated between virtual systems. One Storage Mirroring for Virtual Machines license can be used on up to five virtual servers. Applications This configuration easily protects virtual environments.
3 X Installation Installation Review System Requirements on page 3-1 and Installation and upgrade notes on page 3-2, and then use the appropriate instructions to meet your goal. Installing or upgrading Storage Mirroring on page 3-4—Use these instructions if you are installing or upgrading Storage Mirroring. You can also use these instructions to repair or modify an existing Storage Mirroring installation.
Disk Usage—The amount of disk space required for the Storage Mirroring program files is approximately 70 MB. You will need to verify that you have additional disk space for Storage Mirroring queuing, logging, and so on. Additionally, on a target server, you need sufficient disk space to store the replicated data from all connected sources, allowing additional space for growth.
NOTE: When performing a rolling upgrade, update the target servers first. After the upgrade is complete and the target servers are rebooted, the sources will automatically reconnect to the targets. Upgrade the sources when convenient. If you are using a chained configuration, update the last target first, then update the middle server acting as both a source and target, and update the production source last.
Installing or upgrading Storage Mirroring Use these instructions to install Storage Mirroring or upgrade an existing Storage Mirroring installation. If you are using the same installation files as your existing Storage Mirroring installation, you can modify or repair the existing installation. 1. Close any open applications. 2. Start the installation program using the appropriate instructions, depending on your media source. CD—Load the Storage Mirroring CD into the local CD-ROM drive.
12. After the files have completed copying, click Finish to exit the installation program. NOTE: Depending on your version of Windows and the components installed, you may see an additional button on the last screen of the installation program allowing you to download the Microsoft .NET Framework. If you will be using Server Recovery Option or Full-Server Failover Option, you must download and install the Microsoft .NET Framework. If you do not see this button, your server already has .NET 2.0 or later.
Installing or upgrading Storage Mirroring automatically The Storage Mirroring installation program can accept command-line parameters which allow you to automate the installation or upgrade process by running an unattended, or silent, installation. The automatic process allows you to pass parameters through to the installation program instead of entering information manually during the installation or upgrade.
DTSetup.ini Paramters Parameter DTSetupType Valid Values DTNT—Storage Mirroring server and client components will be installed. DTCO—Storage Mirroring client components will be installed. DTSO—Storage Mirroring server components will be installed. DTActivationCode A 16 or 24 character, alpha-numeric activation code which applies the appropriate license to the server AddOnCodes A 16 or 24 character, alpha-numeric activation code which applies the appropriate add-on code to the server.
7. Run one of the following case-sensitive commands from the temporary directory, depending on if you have setup.exe or setup_xxxx.exe where xxxx is a four digit build number. setup /s /v"DTSETUPINI=\"c:\dtinstall\DTSetup.ini\" /qn" setup_xxxx /s /v"DTSETUPINI=\"c:\dtinstall\DTSetup.ini\" /qn" NOTE: The command must be run from the directory where the temporary files are located as well as specifying that directory for the .ini file. Spacing is critical with this command.
Uninstalling Storage Mirroring Use these instructions if you want to uninstall an existing Storage Mirroring installation. If you want to use the product installation files to uninstall Storage Mirroring, you have to use the same installation files as the currently installed version. If you do not have the same installation files as the currently installed version, you will need to use the Windows Add/Remove Programs feature to uninstall the software.
Uninstalling Storage Mirroring automatically Like the Storage Mirroring installation program, you can automate the uninstall of Storage Mirroring and use the default settings for any prompts. Before you can automate the uninstallation, you must identify the installation ID of the version you have installed. 1. Open the Windows registry and locate HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\ CurrentVersion\Uninstall. 2. Right-click on that registry folder and select Find. 3.
4 X Clients Clients Storage Mirroring has multiple GUI clients that can manage, monitor, and control different aspects and features of Storage Mirroring. The clients include the Management Console, Failover Control Center, and Recovery Manager. Each client can be started from the Windows Start menu. You can also launch the Failover Control Center and the Recovery Manager from the Tools menu in the Management Console.
Logging on and off of Storage Mirroring To ensure protection of your data, Storage Mirroring offers multi-level security using native operating system security features. Privileges are granted through membership in user groups defined on each machine running Storage Mirroring. To gain access to a particular Storage Mirroring source or target, the user must provide a valid operating system user name and password and the specified user name must be a member of one of the Storage Mirroring security groups.
Managing the Management Console Tree To better manage the servers that appear in the Management Console, you can customize the server display to fit your needs. You can create groups and move servers to those groups to help you organize your environment. Within the groups, you can insert, remove, hide or unhide servers. Each of these functions is detailed in the following sections. Groups The left pane of the Management Console is a tree view of the Storage Mirroring servers.
Servers Within your server groups, you do have the ability to further manage the servers that are displayed by using the following functions. Moving Servers—Servers that are auto-populated can be moved to different groups within the Management Console tree. Inserting Servers—If a machine is not displayed on the Management Console, it can be manually inserted. This feature is useful for machines that are across a router or on a different network segment.
Removing servers To remove a server, right-click on the server in the left or right pane of the Management Console and select Remove. You can also select Remove Item from the toolbar. If auto-discovery is enabled on the Management Console, those servers that also have auto-discovery enabled will automatically be repopulated back in the default Auto-Discovered Servers group.
Opening a workspace From the Management Console, you can open a new workspace or open a previously saved workspace. Select File and choose: New Workspace to open an untitled workspace with the default Storage Mirroring window settings. Open Workspace to open a previously saved workspace.
Failover Control Center From the Failover Control Center, you can manage, monitor, and control failover for your Storage Mirroring servers. The Failover Control Center displays a main window for monitoring failover activity. Control buttons to the right allow you to configure and manage your servers. Configuring communication ports The Failover Control Center use two ports for various Storage Mirroring communications.
Recovery Manager If you are using the Server Recovery Option add-on, the Recovery Manager allows you to manage the recovery process for a full server protection connection. The Recovery Manager displays choices for performing the recovery and an interactive window at the bottom to display the validation, configuration, and processing information.
Full-Server Failover Manager If you are using the Full-Server Failover Option add-on, the Full-Server Failover Manager allows you to create your source target connection, monitor your high availability protection, manage Full-Server Failover Option snapshots, and initiate failover.
Configuring Full-Server Failover Manager options You can configure options for the Full-Server Failover Manager client by selecting File, Options. Refresh Interval—By default, the main window of Full-Server Failover Manager will automatically update every five (5) seconds. If desired, you can modify the refresh rate. You can also refresh the main window manually by selecting File, Refresh.
5 X Getting Started Getting Started Your first task in Storage Mirroring is to establish a connection. A connection is the central management object within Storage Mirroring. You create, modify, and monitor connections to protect your data. A connection is made up of a source (the server that contains the data to be protected), the replication set (the data on the source that is being protected), and a target (the server that will maintain a copy of the source’s replication set data).
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6 X Providing Disaster Recovery for an Entire Server Providing Disaster Recovery for an Entire Server If you are using the Storage Mirroring Server Recovery Option (SRO) add-on, you can protect the entire server, including your data and the server’s system state, which is the server’s configured operating system and applications. Using the Connection Wizard, Storage Mirroring automatically creates the replication set for you, selecting all of the data and system state data on the source.
6. By default, all volumes are automatically selected for protection. You can deselect those volumes that you do not want to protect by clearing the checkbox, although if those volumes contain application data, the integrity of your installed applications will not be maintained. You cannot clear the checkbox for the boot volume because that is where the system state information is stored. A replication set will automatically be created using the volumes you select. Click Next to continue. 7.
Recovering an entire server If the source has failed, you can recover it to another server. You will need another similar server, but it does not need to have Storage Mirroring installed on it. Keep in mind the following points when recovering system state and data. The Storage Mirroring Recovery Manager triggers certain processes during a recovery. Therefore, you need to have the Recovery Manager open for the triggers to execute.
6. If desired, you can view and/or modify the optional recovery settings by clicking Configure Recovery. For details on each of the optional settings, see Configuring optional settings on page 6-5. 7. Before starting the recovery, you must validate the configuration of the recovery server to make sure it is suitable for the image of the original source. Click Validate Configuration. The validation results will be displayed in the Validation tab at the bottom of the window.
Incompatibility Level Requirement Error Architecture The recovery server and the image of the source must have the same architecture. For example, you cannot recover a 32-bit server to a 64-bit server. Storage Mirroring path The Recovery Manager must be able to detect the Storage Mirroring installation path. Processors The recovery server should have at least the same number of processors as the image of the source.
Configuring optional settings If you want to configure optional recovery settings, click Configure Recovery from the main Recovery Manager window, after you have selected your target image server and recovery server. Network Adapters—Select a NIC on the recovery server that will assume the identity of each NIC from the original source. You must have the same number of network adapters on the recovery server as you did on the original source.
Managing your Server Recovery Option snapshots If you configured snapshots in your connection through the Management Console, that snapshots will be reflected in the Recovery Manager Snapshot Manager. (The Snapshot Manager (Actions, Snapshot Manager) is only available when a target image server and a recovery server are selected in the Recovery Manager.) If you want to take a snapshot manually, click Take Snapshot.
Running Server Recovery Option from a command line You can initiate recoveries without using the Recovery Manager GUI. The same executable that launches the GUI can be used from a command prompt with options. The command line execution opens the GUI, passes through specified parameters, and initiates specified processes. You may want to use this alternate execution if you have different configuration files that you want to execute or if you have multiple recoveries.
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7 X Providing High Availability for an Entire Server Providing High Availability for an Entire Server With the Storage Mirroring Full-Server Failover feature, you can protect the entire server, including your data and the server’s system state, which is the server’s configured operating system and applications. Using the Full-Server Failover Manager, Full-Server Failover automatically creates a replication set for you, selecting all of the data and system state data on the source.
Compatibility Requirement Level Warning Configuration Memory The target memory should be within 25% (plus or minus) of the source. If the target has much less memory than the source, there will be performance impacts for the users after failover. CPU Count There are no limits on the number or speed of the processors, but the target should have at least the same number of processors as the source.
4. You must validate that your target is compatible with your source and can stand-in if the source fails. Click Validate configuration. You can also select Actions, Validate. The Validation tab at the bottom of Full-Server Failover Manager updates to display the validation check. Errors are designated by a white X inside a red circle. Warnings are designated by a black exclamation point (!) inside a yellow triangle. A successful validation is designated by a white checkmark inside a green circle.
Configuring optional settings If you want to configure optional protection settings, click Configure protection from the main Full-Server Failover Manager window, after you have selected your source and target. You can also select Actions, Configure Protection. There are multiple tabs for different types of protection settings. The Protection tab determines what on the source will be protected and how the target will handle the protection. The Failover tab controls how the failover process will be handled.
Pre-Failover Script and Post-Failover Script—If you want to execute a script on the target before failover (Pre-Failover Script) begins or after failover has occurred (Post-Failover Script), specify the path to the script on the target. You can also search for the script by clicking Browse. The script will be processed using the same user account that is configured to run the Storage Mirroring service. Scripts may contain any valid Windows command, executable, batch, or script file.
Monitoring high availability for an entire server After you have enabled protection, you can monitor the protection from Full-Server Failover Manager. The Protection Status is displayed in the right center of Full-Server Failover Manager. You can tell the status of your protection from this field. Disabled—Protection for the source has not been started. The target must be validated as compatible before you can enable protection. Initializing—Full-Server Failover is initializing protection.
Starting failover When a failover condition is met, you will want to start failover. Additionally, you can start it without a failover condition, as long as protection is enabled. For example, you may want to force failover when upgrading to a better source server. To start failover, click Failover. You can also select Actions, Failover. If Full-Server Failover determines there is a possibility that the data on the target is incomplete, you will be warned before failover begins.
Viewing the log By default, Full-Server Failover Manager logs basic processing information. To view the log file, select File, Logs, View Full-Server Failover Manager Log. The log file will be opened automatically in Notepad. The log file, FFMLog.log, is located in the directory where you installed Full-Server Failover. You can clear the log file by selecting File, Logs, Clear Full-Server Failover Manager Log.
Delete Snapshot—If you no longer want to keep a snapshot, you can delete it by highlighting the snapshot in the Existing Snapshots list and clicking Delete Snapshot. To help you understand the snapshots, use the Type and Status columns. The Status indicates the state of the connection between the source and target at the time the snapshot was taken. the Type information is displayed in the following table. Type Description Scheduled This snapshot was taken as part of a periodic snapshot.
Running Full-Server Failover from a command line You can configure connections and initiate failover without using the Full-Server Failover Manager GUI. The same executable that launches the GUI can be used from a command prompt with options. The command line execution opens the GUI, passes through specified parameters, and initiates specified processes. You may want to use this alternate execution if you have different configuration files that you want to execute or if you have multiple connections.
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8 X Protecting Specific Data Using the Connection Wizard Protecting Specific Data Using the Connection Wizard The Connection Wizard guides you through the process of protecting your data. It helps you select a source, identify the data from your source that will be included in the replication set, and select a target. The connection itself provides disaster recovery protection. If you want to extend the protection and provide high availability, you can add failover monitoring. 1.
6. Choose to create a new replication set or use a replication set that already exists. Create a new replication set with this name—If you choose to create a new replication, specify a replication set name. Use this replication set—If you choose to use an existing replication set, specify the name of that replication set by selecting it from the pull-down menu. Click Next to continue. 7.
9 X Protecting Specific Data Using the Connection Manager Protecting Specific Data Using the Connection Manager When protecting your data through the Connection Manager, you need to create your replication set manually on your own first, and then connect it to your target using the Connection Manager. The connection itself provides disaster recovery protection. If you want to extend the protection and provide high availability, you can add failover monitoring.
Establishing the connection After you have created a replication set, you can establish a connection through the Connection Manager by connecting the replication set to a target. 1. 2. Open the Connection Manager to establish the connection. Highlight the replication set and select Tools, Connection Manager. Right-click on the replication set and select Connection Manager. Drag and drop the replication set onto a target.
Custom Location—If the predefined options do not store the data in a location that is appropriate for your network operations, you can specify your own custom location where the replicated files will be sent. Click the target path and edit it, selecting the appropriate location. NOTE: If you are mirroring and replicating dynamic volumes or mount points, your location on the target must be able to accommodate the amount of data that you are replicating.
Send data only if Source is newer than Target—Only those files that are newer on the source are sent to the target. NOTE: If you are using a database application, do not use the newer option unless you know for certain you need it. With database applications, it is critical that all files, not just some of them that might be newer, get mirrored. Use block checksum—For those files flagged as different, the mirror performs a checksum comparison and only sends those blocks that are different.
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10 X Protecting Data in a Cluster Environment Protecting Data in a Cluster Environment In a MSCS cluster configuration, a single copy of data resides on a SCSI disk that is shared between cluster nodes. Data is available without users knowing which node owns a cluster resource. MSCS handles failover between nodes of the cluster.
3. On your source, create a replication set from the Management Console. NOTE: If your source is a cluster, you need to create the replication set on the node which currently owns the group with the virtual server you want to protect. a. Highlight the source in the left pane of the Management Console and select Insert, Replication Set from the menu bar. You can also right-click on the source name and select New, Replication Set. b. A replication set icon appears in the left pane under the source.
4. If your source is a cluster, you need to create a duplicate replication set on each of the other nodes in the cluster. Because the other nodes do not currently own the files, you will not be able to browse to select the data like you did on the first node. Therefore, you will have to manually enter the replication set data. NOTE: As an alternative to the following manual steps, you can stop the Storage Mirroring service on the other nodes of the source cluster, copy the file DblTake.
5. On your cluster (source and/or target), you need to disable the standard Storage Mirroring connection controls so that the MSCS resource that you will be configuring later can control the Storage Mirroring connections. a. In the Management Console, right-click a node of the source cluster and select Properties. b. Select the Setup tab and clear the Automatically Reconnect During Source Initialization check box. c. Click OK to save the changes. d. Repeat these steps on each node of the cluster(s).
h. 8. Specify your Storage Mirroring bandwidth limiting parameters. No Bandwidth Limit—Data will be transmitted using all available bandwidth. Fixed Bandwidth Limit—Data will be transmitted according to the user-specified bandwidth configuration. By default, the Unlimited checkbox is enabled. This configuration is identical to selecting No Bandwidth Limit. If you want to limit your bandwidth usage, clear this checkbox.
3. Specify the source. 4. Establish a connection from the source to the target using identical drive mappings on the target as on the source. NOTE: 5. Notice that identical drive mappings are used in the online script. If your source and target do not have the same drive letters, the online script will fail. Begin a block checksum mirror. The source will begin replication after the mirror completes. Offline Script used to disconnect a connection 1.
11 X Protecting Data Across a NAT or Firewall Protecting Data Across a NAT or Firewall If your source and target are on opposite sides of a NAT or firewall, you will need special configurations to accommodate the complex network environment. Additionally, you must have the hardware already in place and know how to configure the hardware ports. If you do not, see the reference manual for your hardware.
Configuring the hardware You need to configure your hardware so that Storage Mirroring traffic is permitted access through the router and directed appropriately. Using the port information from the previous section, configure your router identifying each Storage Mirroring server, its IP address, and the Storage Mirroring and router ports. Also, note the following caveats.
12 X Simulating a connection Simulating a connection Storage Mirroring offers a simple way for you to simulate a connection in order to generate statistics that can be used to approximate the time and amount of bandwidth that the connection will use when actively established. This connection uses the TDU (Throughput Diagnostics Utility), which is a built-in null (non-existent) target to simulate a real connection. No data is actually transmitted across the network.
4. Identify the data on the source that you want to protect by selecting volumes, drives, directories, and/or specific files. NOTE: 5. Be sure and verify what files can be included by reviewing Replication capabilities on page 13-2. After selecting the data for this replication set, right-click the new replication set icon and select Save. A saved replication set icon will change from red to black.
Establishing the simulated connection After you have created a replication set, you can establish the simulated connection through the Connection Manager by connecting the replication set to the TDU. 1. 2. Opening the Connection Manager to establish the connection. Highlight the replication set and select Tools, Connection Manager. Right-click on the replication set and select Connection Manager. The Connection Manager opens to the Servers tab.
13 X Managing Replication Sets Managing Replication Sets Depending on how you created your connection, you may have created your replication set by browsing your source and selecting which items to include or Storage Mirroring may have created it for you by automatically selecting specific items from the source.
If you rename the root folder of a connected replication set, Storage Mirroring interprets this operation as a move from inside the replication set to outside the replication set. Therefore, since all of the files under that directory have been moved outside the replication set and are no longer a part of the replication set, those files will be deleted from the target copy of the replication set. This, in essence, will delete all of your replicated data from the target.
b. If you are mirroring/replicating from an NTFS source to a FAT target, you may see additional error messages in your Storage Mirroring log file because the target file system cannot handle the NTFS attributes or file permissions. For example, if your replication set contains files with alternate data streams, you will see messages indicating that there are unfinished operations because the FAT file system cannot store the alternate data stream information. c.
Creating or modifying replication set rules manually There may be times when you cannot browse for data when creating a replication set. For example, you can create a replication set rule for a directory or file that does not exist. Since you cannot browse for the location, you have to create replication set rule manually. At other times, the data you want to replicate cannot be easily selected from the Management Console. For example, you may want to select all .
2. Modify the items by marking or clearing the volume, drive, directory, or file check boxes. Notice the replication set icon has changed from black to red, indicating changes to the replication set rules. 3. After updating the rules for this replication set, right-click the replication set icon and select Save. A saved replication set icon will change from red to black.
Calculating replication set size While Storage Mirroring is mirroring, the right pane of the Management Console displays statistics to keep you informed of its progress. If the size of the replication set is determined before the mirror is started, Storage Mirroring can display the percentage of the replication set that has been mirrored in the Mirror Status column. If the size was not calculated prior to starting the mirror, the column displays Mirroring. 1.
14 X Managing Connections Managing Connections A unique connection ID is associated with each Storage Mirroring connection. The connection ID provides a reference point for each connection. The connection ID is determined by sequential numbers starting at one (1). Each time a connection is established, the ID counter is incremented. It is reset back to one each time the Storage Mirroring service is restarted.
Monitoring connections When a source is highlighted in the left pane of the Management Console, the connections and their statistics are displayed in the right pane. Additionally, colors and icons are used for the connections, and the Storage Mirroring servers, to help you monitor your connections. Review the Connection Statistics and Connection and Server Display tables for statistics and status descriptions. (Statistics marked with an asterisk (*) are not displayed, by default.
Statistic Mirror Status Description Mirroring—If the file size of the replication set has not been calculated and the data is being mirrored to the target machine, the Mirror Status will indicate Mirroring. Idle—Data is not being mirrored to the target machine. Paused—Mirroring has been paused.
Statistic Description Skipped Mirror (Bytes) The skipped mirror (bytes) statistic is the total number of bytes that have been skipped when performing a difference or checksum mirror. These bytes are skipped because the data is not different on the source and target machines. Remaining Mirror (Bytes) The remaining mirror (bytes) statistic is the total number of mirror bytes that are remaining to be sent to the target.
Location Icons displayed in the right pane when a group is highlighted in the left pane Icon or Color Description An icon with a network cable between two servers on the right pane indicates there are no established Storage Mirroring connections to this server. This icon also indicates that communications between the Management Console and the server are working properly. An icon with two servers on the right pane indicates this server has active connections that are working properly.
3. Under Site Monitor, specify Missed Status Responses to identify the number of responses from a server that can be missed before the Management Console considers communications lost and updates the icons. Valid values are between 1 and 100. The default setting is 2. 4. Under Connection Monitor, specify Missed Status Responses to identify the number of responses from a server that can be missed before the Management Console considers communications lost and updates the icons and colors.
2. To control the window after it is created, use either of the following methods to access the control methods listed in the table: Right-click on the message window and select the appropriate control. Select the appropriate toolbar control. Select Monitor, the name of the message window, and the appropriate control. Message Window Description Control Close Closes the message window Clear Clears the message window Pause/ Resume Toolbar Icon Pauses and resumes the message window.
Start—If you select to start a mirror, you will need to make the following two selections on the Start Mirror dialog box. Full Mirror—All files in the replication set will be sent from the source to the target. File Differences—Only those files that are different based on date, time, and/or size will be sent from the source to the target. Send data only if Source is newer than Target—Only those files that are newer on the source are sent to the target.
Controlling an automatic mirror In certain circumstances, for example if the disk-based queues on the source are exhausted, Storage Mirroring will automatically disconnect connections (called auto-disconnect) and then automatically reconnect them (called auto-reconnect). In order to ensure data integrity on the target, Storage Mirroring will perform an automatic mirror (called an auto-remirror) after an auto-reconnect. Auto-remirror is a per source option.
Configuring customized mirroring scripts You can customize your mirroring process by running customized scripts on the target at predefined points in the mirroring process. For example, you may want to send a notification when a mirror starts or initiate a backup when a mirror is complete. Scripts may contain any valid Windows command, executable, batch, or script file.
Configuring compression To help reduce the amount of bandwidth needed to transmit Storage Mirroring data, compression allows you to compress data prior to transmitting it across the network. In a WAN environment this provides optimal use of your network resources. If compression is enabled, the data is compressed before it is transmitted from the source. When the target receives the compressed data, it uncompresses it and then writes it to disk.
Configuring and removing orphan files An orphan file is a file that exists in the target’s copy of the replication set data, but it does not exist in the source replication set data. An orphan file can be created when you delete a file contained in the source replication set while there is no Storage Mirroring connection. For example, if a connection was made and a mirror was completed and then the connection was stopped and a file was deleted on the source, an orphan file will exist on the target.
4. By default, the orphan files feature is disabled. To enable it, mark Move/Delete Orphan Files. 5. Specify if you want to Delete Orphaned Files or Move Orphaned Files to a different location. If you select the move option, identify the location where these orphan files will be located. If you are moving files, make sure the directory you specify to move the files to is not included in the destination of the replication set data so that the orphan files are only moved once. NOTE: 6.
Use block checksum comparison/delta block transfer—Specify if you want the verification process to use a block checksum comparison to determine which blocks are different. If this option is enabled, only those blocks (not the entire files) that are different will be identified in the log and/or remirrored to the target. NOTE: 3. Database applications may update files without changing the date, time, or file size.
7. Specify if you want the verification process to Use block checksum comparison/delta block transfer to determine which blocks are different. If this option is enabled, only those blocks (not the entire files) that are different will be identified in the log and/or remirrored to the target. NOTE: 8. Database applications may update files without changing the date, time, or file size.
7. Specify the Language of the log file. Currently, English is the only available language. 8. Click OK to save the settings. In the log file, each verification process is delineated by beginning and end markers. A list of files that are different on the source and target is provided as well cumulative totals for the verification process. The information provided for each file is the state of its synchronization between the source and the target at the time the file is verified.
the mask corresponds to the attributes of a file. 1. Each mask begins with 0x. Identify the hexadecimal number after the constant 0x. For example, if the mask is 0x23, then the hexadecimal number you are interested in is 23. The hexadecimal number may be up to four digits. 2. Convert the hexadecimal number to its 16-digit binary equivalent. You can use the Windows calculator for this conversion. a. Select Start, Programs, Accessories, Calculator. b.
compare a current revision of a file with an older revision. Storage Mirroring utilizes snapshot functionality by allowing you to create snapshots of the replicated data stored on the Storage Mirroring target. Storage Mirroring snapshot functionality ensures that you will always have usable data on the target. For example, if your source server becomes infected with a virus, you can revert to a previous snapshot of the data on the target that was created prior to the virus infection.
Understanding When to Take a Snapshot A snapshot may not necessarily be useful if the data on the target is in a bad state. You only want snapshots of data that is in a good state. Therefore, you need to understand when the data is in a good or bad state. Automatic Action Action State Description Taken for Scheduled and Automatic Snapshots User Interaction Required for Manual Snapshots Mirror Started Bad Mirroring has started, but is not complete.
Automatic Action Action State Description Taken for Scheduled and Automatic Snapshots User Interaction Required for Manual Snapshots Restore Required Good or Bad The data on the target no longer matches the data on the source because of a failover. This does not necessarily mean that the data on the target is bad. Scheduled and automatic snapshots will be delayed until a restore is completed or the Restore Required state is overruled by a mirror.
Automatic Snapshots Storage Mirroring snapshot capability is enabled by default for those servers running Windows 2003. In order to protect your data on the target, Storage Mirroring automatically takes snapshots at certain times. When Storage Mirroring transitions from a good state to a bad state, it will automatically attempt to take a snapshot of the data before it leaves the good state and enters the bad state.
Queuing Storage Mirroring data During the Storage Mirroring installation, you identified the amount of disk space that can be used for Storage Mirroring queuing. Queuing to disk allows Storage Mirroring to accommodate high volume processing that might otherwise fill up system memory. For example, on the source, this may occur if the data is changing faster than it can be transmitted to the target, or on the target, a locked file might cause processing to backup.
Configuring queuing You should configure queuing on both the source and target. 1. Right-click the server on the left pane of the Management Console and select Properties. 2. Select the Queue tab. 3. Specify the Folder where the disk queue will be stored. Storage Mirroring displays the amount of free space on the volume selected. Any changes made to the queue location will not take effect until the Storage Mirroring service has been restarted on the server.
4. Specify the Maximum system memory for queue. This is the amount of Windows system memory, in MB, that will be used to store data in queues. When exceeded, queuing to disk will be triggered. This value is dependent on the amount of physical memory available but has a minimum of 32 MB. By default, 128 or 512 MB of memory is used, depending on your operating system. If you set it lower, Storage Mirroring will use less system memory, but you will queue to disk sooner which may impact system performance.
Configuring automatic reconnections While disk queues are user configurable and can be extensive, they are limited. If the amount of disk space specified for disk queuing is met, additional data could not be added to the queue and data would be lost. To avoid any data loss, the auto-disconnect and auto-reconnect processes occur. Exhausted queues on the source—If disk queuing is exhausted on the source, Storage Mirroring will automatically start disconnecting connections. This is called auto-disconnect.
Blocking target paths You can block writing to the paths on the target that contain the copy of the replication set data. This keeps the data from being changed outside of Storage Mirroring processing. To block the replication set data paths on the target, right-click the connection on the right pane of the Management Console and select Block Target Path(s). To unblock the paths, right-clikc the connection and deselect Block Target Path(s).
15 X Managing Data Transmission Managing Data Transmission Storage Mirroring data is continuously transmitted to the target machine. Although the data may be queued if the network or target machine is slow, the default transmission setting is to transmit the data as soon as possible. You can modify the tranmission to suit your environment.
At the top of the Transmit tab dialog box, the Enable Transmission Limiting check box allows you to turn the transmission options on or off. You can enable the transmission options by marking the Enable Transmission Limiting check box when you want the options to be applied, but you can disable the transmission options, without losing the settings, by clearing that check box.
4. Schedule any desired stop criteria to stop transmission after a transmission start criteria has initiated the transmission. If you do not establish a stop criteria, transmission will end when the queue is empty. Select the Stop option in the Limit Type box. Define the stop options to stop Storage Mirroring transmissions by using either or both of the following options. Time Limit—The time limit specifies the maximum length of time for each transmission period.
Define a window to control Storage Mirroring transmissions by enabling the feature and then specifying both window options. Enable Transmission Window—This option specifies whether a transmission window is in use. Open window time—Specifies the time, formatted for AM or PM, when the transmission window will open, allowing Close window time—Specifies the time, formatted for AM or PM, when the transmission window will close, stopping transmission to begin. all transmission. 6.
Setting bandwidth limitations Bandwidth limitations are available to restrict the amount of network bandwidth used for Storage Mirroring data transmissions. The network administrator specifies a percentage of bandwidth that is available or an absolute bandwidth limit for Storage Mirroring transmissions and Storage Mirroring never exceeds that allotted amount. The bandwidth not in use by Storage Mirroring is available for all other network traffic. You can schedule when you want bandwidth limiting to occur.
6. If you want to transmit data according to a schedule using limited bandwidth, select Scheduled Bandwidth Limit. a. 7. Click New Event to create a bandwidth schedule event. 1. Specify a name for the bandwidth schedule event. 2. Select the day(s) of the week that you want this event to be iniitated on. 3. Specify the time when you want this event to start. 4. Specify the bandwidth limitation. a. By default, the Unlimited checkbox is enabled.
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16 X Failover Failover Failover is the process in which a target stands in for a failed source. As a result, user and application requests that are directed to the failed source are routed to the target. Storage Mirroring monitors the source status by tracking network requests and responses exchanged between the source and target. When a monitored source misses a user-defined number of requests, Storage Mirroring assumes that the machine has failed.
Configuration requirements Storage Mirroring failover can be implemented with very little configuration necessary in small or simple networks, but additional configuration may be required in large or complex environments. Because an infinite number of network configurations and environments exist, it is difficult to identify all of the possible configuration steps required for failover.
WINS When Storage Mirroring failover occurs, Windows initiates WINS registration with the target’s primary WINS server to associate the source server’s name with the target’s primary IP address. In an environment with just one WINS server, no additional processing is required. In an environment with more than one WINS server, WINS replication will distribute the updated WINS registration to other WINS servers on the network.
WINS replication WINS replication can be added to your failover and failback scripts by using the Windows NETSH command with the WINS set replicate context. Add the following command to your failover and failback scripts. netsh wins server target’s_primary_wins_server_IP_address set replicateflag 1 Substitute the IP address of the target’s primary WINS server for the variable target’s_primary_wins_server_IP_address. For example, suppose you had the following environment.
DNS When Storage Mirroring failover occurs, DNS is not automatically updated. If the end-users use DNS to resolve server names and the source IP address was not failed over to the target, additional DNS updates will be required because the host records for the source will remain intact after failover. You can automate this process by scripting the DNS updates in the failover and failback scripts. You have two options for scripting the DNS updates.
You would add the following to your failover script to delete the host and reverse lookup entries and add new entries associating the source to the target. Sample Post-Failover Script for DNS Updates Using DNSCMD dnscmd dnscmd dnscmd dnscmd DNSServer.domain.com DNSServer.domain.com DNSServer.domain.com DNSServer.domain.com /RecordDelete domain.com alpha A 192.168.1.108 /f /RecordDelete 192.168.in-addr.arpa 108.1 PTR alpha.domain.com /f /RecordAdd domain.com alpha A 116.123.2.47 /RecordAdd 116.123.
5. Add the appropriate DFO command to your failover script using the following command syntax.
Examples dfo /dnssrvname gamma.domain.com /srcname alpha.domain.com /srcip 206.31.4.10 /tarip 210.11.12.13 /username domain.com\admin /password password /verbose (Modifies all resource records on the specified DNS server that match the source criteria, using the username and password to connect to the DNS server) dfo /dnssrvname gamma.domain.com /srcname alpha.domain.com /srcip 210.11.12.13 /tarname beta.domain.com /tarip 206.31.4.
Macintosh shares A share is any volume, drive, or directory resource that is shared across a network. During failover, the target can assume or add any source shares so that they remain accessible to the end users. Automatic share failover only occurs for standard Windows file system shares. Other shares, including Macintosh volumes, must be configured for failover through the failover scripts or created manually on the target. 1. On your target, set the File Server for Macintosh service to manual startup.
NFS shares A share is any volume, drive, or directory resource that is shared across a network. During failover, the target can assume or add any source shares so that they remain accessible to the end users. Automatic share failover only occurs for standard Windows file system shares. Other shares, including NFS shares, must be configured for failover through the failover scripts or created manually on the target. 1. On your target, set the NFS service to manual startup.
Configuring failover 1. The Failover Control Center can be started from within the Management Console or from the Windows desktop. From the Management Console, select Tools, Failover Control Center. From the Windows desktop, select Start, Programs, Storage Mirroring, Failover Control Center. 2. Select a failover target from the Target Machine list box. NOTE: If the target you need is not listed, click Add Target and manually enter a name or IP address (with or without a port number).
10. Highlight an IP address that you have selected for monitoring and select the Missed Packets. This setting is the number of monitor replies sent from the source to the target that can be missed before assuming the source machine has failed. This option is not configurable if your Method to Monitor for Failover is set to No Monitoring. Repeat this step for each IP address that is being monitored. NOTE: To achieve shorter delays before failover, use lower Monitor Interval and Missed Packets values.
12. If Manual Intervention is enabled, Target Data State at Failover will be disabled because the same options will be presented to you at failover time. If Manual Intervention is disabled, the options will be enabled so that an option can be selected to occur automatically when failover occurs. Highlight the source name and specify the Target Data State at Failover by specifying what data you want to use on the target when failover occurs.
14. By default, Manual Intervention is enabled, allowing you to control when failover occurs. When a failure occurs, a prompt appears in the Failover Control Center and waits for you to manually initiate the failover process. Disable this option only if you want failover to occur immediately when a failure occurs. This option is not configurable if the Method to Monitor for Failover is set to No Monitoring. 15. If the Shares selection under Items to Failover is selected, verify that the Use .
Editing failover configuration If you want to edit the monitor settings for a source that is currently being monitored, highlight that source on the Monitored Machines tree on the main Failover Control Center screen and click Edit. The Monitor Settings dialog box will open. Follow the instructions under Configuring failover on page 16-11.
The following table identifies how the visual indicators change as the status of failover changes. Time to Fail Countdown Source is Online Source Fails and Failover is Initiated Failover is Complete Status Bar Colored Bullets Desktop Icon Tray The Time to Fail counter is counting down and resetting each time a response is received from the source machine. The status bar indicates that the target machine is monitoring the source machine. The bullets are green.
Failover manual intervention If Manual Intervention is enabled, the Failover Control Center will prompt you when a failure occurs. NOTE: If the Failover Control Center is not running at the time the failure occurs, the manual intervention dialog box will appear the next time the Failover Control Center is started. When a failure occurs, an alert is forwarded to the Windows Event Viewer. You can then start the Failover Control Center and respond to the manual intervention prompt.
17 X Restoration for Disaster Recovery Restoration for Disaster Recovery If you are not using failover and your connection is for disaster recovery, the Management Console provides an easy method for restoring replicated data from the target back to the original source or to a new source server. You are only required to input the original source, the target, and the name of the replication set you want to restore.
Overwrite existing files during restore—This option restores all existing files by overwriting them. Any files that do not exist on the source are written also. If this option is disabled, only files that do not exist on the source will be restored. Only if backup copy is more recent—This option restores only those files that are newer on the target than on the source. The entire file is overwritten with this option.
18 X Restoration and Failback for High Availability Restoration and Failback for High Availability With a high availability connection, failover occurred because the target was monitoring the source for a failure, and when a failure occurred, the target stood in for the source. User and application requests that were directed to the failed source are routed to the target. While the users are accessing their data on the target, you can repair the issue(s) on the source.
10. Begin your restoration process. a. From the Management Console on the target, select Tools, Restoration Manager. b. Select the Original Source machine. This is your source machine where the data originally resided. c. Select the Restore From machine. This is the target machine where the copy of the data is stored. d. Replication Set contains the replication set information stored on the target machine (the machine in Restore From). If no replication sets are available, the list will be blank.
Use block checksum comparison/delta block transfer—Specify if you want the restoration process to use a block checksum comparison to determine which blocks are different. If this option is enabled, only those blocks (not the entire files) that are different will be restored to the source. j. If you want to configure orphan files, click the Orphans tab. The same orphan options are available for a restoration connection as a standard connection.
Failback then restoration Failback before restoration can be a simpler process, but it may require additional downtime. The amount of downtime will depend on the amount of data to be restored. Users must be kept off of the source and target during this entire process. 1. Resolve the problem(s) on the source that caused it to fail. Make sure in resolving the problems, that you do not bring the source on the network at this time because the target currently has the source’s identity because of failover. 2.
d. Replication Set contains the replication set information stored on the target machine (the machine in Restore From). If no replication sets are available, the list will be blank. Select the replication set that corresponds to the data that you need to restore. e. Select the Restore To machine. This is your source where the updated data from the target will be sent. f. The Restore To and Restore From paths will automatically be populated when the replication set is selected.
19 X Monitoring Tools Monitoring Tools In addition to the monitoring capabilities within the Storage Mirroring clients, you can monitor Storage Mirroring processing using other tools. Log files are generated for various Storage Mirroring components recording alerts (notifications, warnings, and errors). These log files can be viewed using a standard text viewer, and their output can be filtered using the Storage Mirroring LogViewer utility. See Log Files on page 19-2.
Log Files Various Storage Mirroring components (Storage Mirroring service, Management Console, Failover Control Center, Text Client, and the Command Line Client) generate a log file to gather alerts, which are notification, warning, and error messages. The log files are written to disk. They can be viewed, from the location where Storage Mirroring is installed, with a standard text viewer. The log file output can be filtered using the Storage Mirroring LogViewer utility.
Viewing the log files The log files can be viewed, from the location where Storage Mirroring is installed, with a standard text viewer. Sample Storage Mirroring Service Log File 01/15/2007 01/15/2007 01/15/2007 01/15/2007 01/15/2007 01/15/2007 01/15/2007 01/15/2007 01/15/2007 01/15/2007 01/15/2007 01/15/2007 14:14:18.3900 14:14:18.4200 14:14:18.5350 14:14:18.6760 14:14:18.9870 14:24:15.2070 14:24:16.3090 14:24:40.9680 14:25:22.4070 14:25:22.5030 14:25:22.6060 14:25:23.
Using LogViewer Log file output can be filtered using the Storage Mirroring LogViewer utility. Use the LogViewer command from the directory where Storage Mirroring is installed. Command LOGVIEWER Description The Storage Mirroring logging utility that records alerts (processing notifications, warnings, and errors) that occur during Storage Mirroring processing.
Log messages The following table describes some of the standard Storage Mirroring alerts that may be displayed in the log files. The ID appears in column 7 of the log file, and the message appears in column 8. In the following table, con_id refers to the unique connection ID assigned to each connection between a source replication set and a target. NOTE: ID Message Description 0 N/A There are several log messages with this ID#. See the description in the Message column in the LogViewer file.
ID Message Description 79 Memory freed to bring Storage Mirroring memory usage below the limit Data in the source queue has been sent to the target machine, bringing the pagefile below its limit. 80 Trying to auto-retransmit to ip://xxx.xxx.xxx.xxx Storage Mirroring is attempting to automatically reconnect previously established source and target connections after a server reboot or auto-disconnect. This is also referred to as the auto-reconnect process.
ID Message Description 102 Target full! The disk to which data is being written on the target is full. This issue may be resolved by deleting files on the target machine or by adding another disk. 801 Auto-disconnect has occurred on IP address address with connection con_id Disconnected replication set name: repset_name. Auto-disconnect has occurred for the specified connection. This is due to the source queue filling up because of a network or target failure or bottleneck.
ID Message Description 53003 Could not read filename Storage Mirroring could not read a file on the source machine because the file may have been renamed or deleted. For example, temporary files show up in queue but do not show up during transmission. (No user action required.) 54000 Kernel started The Storage Mirroring service was started. 54001 Failover module failed to load The Storage Mirroring failover module failed to load. Look at previous log messages to determine the reason.
Windows Event Viewer In the Windows operating system, an event is a significant occurrence in the system or in an application that requires administrators to be notified. The operating system writes notifications for these events to a log file that can be displayed using the Windows Event Viewer. Three different log files are generated: system, security, and application logs. Storage Mirroring related events are sent to the application log and are available for viewing through the Event Viewer. 1.
ID Category Severity Event Message Required Response 1002 DTCounters Error The Storage Mirroring counter DLL could not map shared memory file containing the performance data. Run the installation and select Repair. Contact technical support if this event occurs again. 1003 DTCounters Error The Storage Mirroring counter DLL could not open the "Performance" key in the Storage Mirroring section of the registry. Run the installation and select Repair.
ID Category Severity Event Message Required Response 4015 Service Info. Service has stopped network transmission. No action required. 4016 Service Info. Service has established a connection to %1 (%2) for Replication Set %3, ID: %4 No action required. 4017 Service Info. Service has disconnected from %1 (%2) for Replication Set %3, ID: %4 No action required.
ID Category Severity Event Message Required Response 4033 Service Error RSResource.dll build version is invalid. The product functionality has been disabled. Reinstall the software, using the installation Repair option, to install a new copy of the RSResource.dll. Contact technical support if this error persists. 4034 Service Error Error verifying the service name. The product functionality has been disabled.
ID Category Severity Event Message Required Response 4044 Service Error An error was encountered and replication has been stopped. It is necessary to stop and restart the service to correct this error. Contact technical support if this error persists. 4045 Service Error %1 value must be between 1025 and 65535. Using default of %2. Verify that the Storage Mirroring port value you are trying to use is within the valid range. If it is not, it will automatically be reset to the default value.
ID Category Severity Event Message Required Response 4061 Service Info. Service has stopped a verification task to %1 (%2) for Replication Set %3, ID: %4 No action required. 4062 Service Info. Service has completed a verification task to %1 (%2) for Replication Set %3, ID: %4 No action required. 4063 Service Info. Bandwidth limit to %1 (%2) has changed to %3. No action required. 4064 Service Info. Bandwidth limit to %1 (%2) is now in the "%3" period at %4. No action required.
ID Category Severity Event Message Required Response 4100 System Warning Failed to obtain a name for a recognizer device object. The second to the last Word in the Data Window is a pointer to the device object. The last Word in the Data Window is the NT status code. Contact technical support. 4101 Activation Key Error This service will not run on this device. Contact your sales representative for upgrade procedures.
ID Category Severity Event Message Required Response 4201 Service Warning In band task %1 discarded (submitted from %2 by %3 at %4) A task may be discarded in the following scenarios: all connections to a target are manually disconnected, replication is stopped for all connections to a target, or an auto-disconnect occurs. If one of these scenarios did not cause the task to be discarded, contact technical support. 4202 Service Info.
ID Category Severity Event Message Required Response 4401 Service Error Failed to delete automatic snapshot set for source %1 (%2) Connection ID: %3. Error: %4 The automatic snapshot could not deleted. This may be due to a lack of memory, the file does not exist, or another reason. The error code is the Microsoft Volume Shadow Copy error. Check your Volume Shadow Copy documentation or contact technical support.
ID Category Severity Event Message Required Response 5103 Failover Info. Started adding drive shares from %1 to %2. No action required. 5104 Failover Info. %1 drive shares were taken over by %2. No action required. 5105 Failover Info. Attempting to run the %1 script. No action required. 5106 Failover Info. The %1 script ran successfully. No action required. 5107 Failover Error Error occurred in running %1 script.
ID Category Severity Event Message Required Response 5502 Service Warning E-mail notification could not be initialized. Check to make sure Internet Explorer 5.0 or later is installed. E-mail notification requires Internet Explorer 5.0 or later. Verify that you have this version or later installed on the Storage Mirroring server. 5503 Service Warning E-mail notification could not be processed. Check to make sure the correct version of SMTPMail.DLL is registered on the system (error code: %1).
ID Category Severity Event Message Required Response 8196 Resources Warning The maximum amount of memory for replication queuing has been reached. Replication is stopped and memory is being freed. Contact technical support if this event occurs again. 8197 Resources Error Failed to create file delete queue. The last Word in the Data Window is the NT status code. Reboot the server and contact technical support if this event occurs again. 8198 Resources Error Failed to save the registry path.
ID Category Severity Event Message Required Response 9007 NSIPHDriver Error Could not write registry value for IP address list for adapter Reboot the server and contact technical support if this event occurs again. 9008 NSIPHDriver Error Could not write registry value for subnet mask list for adapter Reboot the server and contact technical support if this event occurs again.
ID Category Severity Event Message Required Response 16395 DblTake Warning Dblhook detected a hard link for a file. The volume GUID and file ID are stored in the Data Window. This file will not be replicated. Files with hard links are not supported. 16396 DblTake Info. The driver made more than one pass before finding a valid buffer. The last Word in the Data Window indicates the number the tries. Contact technical support if this event occurs again.
DTStat Statistics logging is the process of taking snapshots of Storage Mirroring statistical data. The data can be written to a file for future use. Changes to the DTStat file configuration are detected and applied immediately without restarting the Storage Mirroring service. The statistics log file created is a binary file. To view the log file, you must run DTStat from the command prompt.
Configuring the statistics file 1. Right-click a machine in the left pane of the Management Console and select Properties. 2. Select the Logging tab. 3. At the top of the tab, specify the Folder where the log files for messages, alerts, verification, and statistics will be saved. 4. Under Statistics, specify the following information: Filename—The name of the statistics log file. The default file name is statistic.sts. Maximum Length—The maximum length of the statistics log file.
Running DTStat from the command prompt From a command prompt, use the DTStat command from the location where Storage Mirroring is installed. Command DTSTAT Description Starts the DTStats statistics logging utility from a command prompt.
DTStat statistics The following statistics appear in the default statistic.sts file. NOTE: If you convert that file to an ASCII, comma-delimited file using the dtstat -s option, the heading labels may appear slightly different. The categories you see will depend on the function of your server (source, target, or both). If you have multiple IP addresses connected to one target server, you will see multiple Target statistic sections for each IP address.
Category Kernel Target Source Connection Statistic Description ActFailCount The number of activation code failures when loading the source or target. Activation codes can be bad for reasons such as: expiration of evaluation codes, duplicate codes, incorrect codes, etc.
Category Connection Statistic conState Description The state of the active connection 0—None. This indicates a connection has not been established. Statistics are still available for the source and target machines. 1—Active. This indicates that the connection is functioning normally and has no scheduling restrictions imposed on it at this time. (There may be restrictions, but it is currently in a state that allows it to transmit.) 2—Paused. This indicates a connection that has been paused. 4—Scheduled.
Category Statistic Description Connection conMirrorBytes Remain The number of mirror bytes remaining to be transmitted conMirror Percent The percentage of the mirror that has been completed. This field is determined if the replication set size was calculated.
Windows Performance Monitor Performance Monitor is a graphical tool for measuring the performance. It provides charting, alerting, and reporting capabilities that reflect both current activity and ongoing logging. Storage Mirroring statistics are available through the Performance Monitor. 1. To access the Performance Monitor, select Programs, Administrative Tools, Performance. 2. Add data to monitor by right-clicking and selecting Add or using the add button from the toolbar. 3.
Object Kernel Security Source Target a Statistic Description Driver Queue Percent The amount of throttling calculated as a percentage of the stop replicating limit Failed mirror operations The number of mirror operations on the source that failed due to an error reading the file from the disk Failed replication operations The number of replication operations on the source that failed due to an error reading the file from the disk Mirror Kbytes generated The number of mirror kilobytes transmitte
SNMP SNMP, Simple Network Management Protocol, is the Internet's standard for remote monitoring and management of hosts, routers and other nodes and devices on a network. Storage Mirroring provides an SNMP sub-agent that monitors Storage Mirroring and can be managed from an SNMP Management Console. Storage Mirroring installs two components to work with SNMP. The sub-agent is a program that installs and runs on the same machine as Storage Mirroring and gathers statistics, data, and traps.
Object Type Source Statistic dtSourceState Description 0—Source is not running 1—Source is running without the replication driver 2—Source is running with the replication driver.
Object Type Connection Statistic Description dtconBytesRx The total number of bytes received from the target dtconResentOpCount The number of operations that were resent because of acknowledgement errors SNMP traps The following tables identify the Storage Mirroring traps provided through SNMP.
Object Type Mirroring Trap Description dttrapMirrorStart Mirroring has started dttrapMirrorStop Mirroring has stopped dttrapMirrorPause Mirroring has paused dttrapMirrorResume Mirroring has resumed dttrapMirrorEnd Mirroring has ended dttrapVerificationStart Verification has started dttrapVerificationEnd Verification has ended dttrapVerificationFailure Verification has failed dttrapRestoreStarted Restoration has started dttrapRestoreComplete Restoration is complete Replication Sets dt
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20 X Server Settings Server Settings Most of the Storage Mirroring server settings are located in the Management Console Server Properties dialog box. To access this dialog box, right-click a server in the left pane of the Management Console and select Properties. The Server Properties dialog box contains multiple tabs with the Storage Mirroring server settings. For information on the server settings not available through the Management Console, see the Scripting Guide.
General The General tab identifies the server. Nickname—A nickname is saved in the Management Console workspace, therefore, it only appears in the Management Console on this server. It is not communicated across the network. If you export a workspace and use it on another Storage Mirroring server, the server nickname will appear there also. Machine—This is the actual server name. This field is not modifiable.
Licensing The Licensing tab identifies the Storage Mirroring license(s) applied to the server. The display for this tab will vary depending on different licensing requirements. Activation Code—This is the Storage Mirroring license which is required on every Storage Mirroring server. There are different licenses available. Evaluation—An evaluation license has an expiration date built into the activation code. When the license expires, the software will no longer function.
Setup The Setup tab contains various setup options. Log Statistics Automatically—If enabled, Storage Mirroring statistics logging will start automatically when Storage Mirroring is started. Enable Task Command Processing—Task command processing is a Storage Mirroring feature that allows you to insert and run tasks at various points during the replication of data. Because the tasks are user-defined, you can achieve a wide variety of goals with this feature.
Network The Network tab contains settings that control network communications. Any changes made to this tab will not take effect until the Storage Mirroring service has been restarted on the server. Default Address—On a machine with multiple NICs, you can specify which address Storage Mirroring traffic will use. It can also be used on machines with multiple IP addresses on a single NIC. Default Protocol—The default protocol for all Storage Mirroring communications is the TCP/IP protocol.
Queue The Queue tab contains settings for Storage Mirroring queue usage. Folder—This is the location where the disk queue will be stored. Storage Mirroring displays the amount of free space on the volume selected. Any changes made to the queue location will not take effect until the Storage Mirroring service has been restarted on the server. Select a location on a volume that will have minimal impact on the operating system and applications being protected.
Maximum system memory for queue—This is the amount of Windows system memory, in MB, that will be used to store data in queues. When exceeded, queuing to disk will be triggered. This value is dependent on the amount of physical memory available but has a minimum of 32 MB. By default, 128 or 512 MB of memory is used, depending on your operating system. If you set it lower, Storage Mirroring will use less system memory, but you will queue to disk sooner which may impact system performance.
Source The Source tab contains settings specific to the source module of Storage Mirroring. Replication Packets to 1 Mirror Packet—You can specify the ratio of replication packets to mirror packets that are placed in the source queue. Specify a larger number if you have a busy network that has heavy replication. Also, if you anticipate increased network activity during a mirror, increase this number so that the replication queue does not get too large.
Ignore Delete Operations—This option allows you to keep files on the target machine after they are deleted on the source. When a file is deleted on the source, that delete operation is not sent to the target. (All edits to files on the source are still replicated to the target; only deletions of whole files are ignored.) This option may be useful to give you an opportunity to make a backup of these files in the event they are needed in the future.
Target The Target tab contains settings specific to the target module of Storage Mirroring. Target Mirror Capacity High Percentage—You can specify the maximum percentage of Windows system memory that can contain mirror data before the target signals the source to pause the sending of mirror operations. The default setting is 20.
Remove after the following number of days—If you are moving deleted files, you can specify a length of time to maintain the delete files. After the time has expired, the moved files will be deleted. NOTE: If deleted files are moved for long enough, the potential exists for the target to run out of space. In that case, you can manually delete files from the target move location to free space.
Database The Database tab identifies the Storage Mirroring database files. Folder—Specify the directory where each of the database files on this tab are stored. The default location is the directory where the Storage Mirroring program files are installed. Replication Set—This database file maintains which replication sets have been created on the server along with their names, rules, and so on. The default file name is DblTake.db.
Logging The Logging tab contains settings for various Storage Mirroring log files. Folder—Specify the directory where each of the log files on this tab are stored. The default location is the directory where the Storage Mirroring program files are installed. Messages & Alerts Maximum Length—Specify the maximum length of the client and service log files. The default size is 1048576 bytes and is limited by the available hard drive space.
Script credentials The Script Credentials tab specifies the security credentials to use when running customized scripts. If you will be using any customized scripts (mirroring, failover, task command processing, and so on) specify a Username, Password, and Domain to use when running the scripts. If you do not specify any security credentials, the account running the Storage Mirroring service will be used.
E-mail notification The E-mail Notification tab allows you to specify e-mail notification settings. When enabled, the messages logged to the Windows Event Viewer will be sent as e-mail messages to the addresses specified. The subject of the e-mail will contain an optional prefix, the server name where the Event Viewer message was logged, the Event Viewer ID, and the severity level (information, warning, or error). The text of the Event Viewer message will be displayed in the body of the e-mail message.
Filter Contents—Specify which Event Viewer messages that you want to be sent via e-mail. Specify Information, Warning, and/or Error. You can also specify which Event Viewer messages to exclude based on the Event ID. Enter the Event IDs as a comma or semicolon separated list. You can indicate ranges within the list. NOTE: You can test e-mail notification by specifying the options on the E-mail Notification tab and clicking Test.
21 X Error Codes Error Codes You may see error codes used in the user interfaces, log files, or in response to Storage Mirroring DTCL commands, This chapter contains a complte list of Storage Mirroring error codes.
Error Code Description -131 No Storage Mirroring target identified -132 Memory is low -133 Memory is sufficient -134 Replication is pending -135 Invalid option supplied -136 Replication set rule does not exist -137 Mirror queue is full -138 Insufficient security access -139 Schedule command is invalid -140 Source path is invalid -141 Replication set is not changed -142 Insufficient source security access -143 Invalid statistics file -144 Replication set not saved -145 Connecti
Error Code Description -167 Restore required state is unknown -168 Not a valid failover source -169 Failover login failed -170 Feature is not supported -171 Command is not supported -172 Target queue log file error -173 Target disk is full -174 Target disk has sufficient disk space -175 Error reading from or writing to the queue log file -176 Memory-based queue is in use -177 Disk-based queue is in use -178 Restore is required -179 ID the driver supplied to the service is invalid
Error Code Description -213 IP address placeholders on the target are unavailable -214 Target NIC was not found -215 Source module is not loaded -216 Failed to set the source state -217 Unable to ping source -218 Invalid argument -219 Recovery is busy -220 Invalid command -221 Recovery is started -222 Script failed to start -223 Script timeout met -224 No replication timeout met - connection is bad -225 Invalid path -226 Kernel module is not loaded -2201 Error communicating wi
Error Code Description -2303 Bandwidth limit not found -2304 Bandwidth limit day is invalid -2305 Bandwidth limit lable is invalid -2401 Snapshot module is not loaded -2402 Error reading the snapshot .
22 X Security Security To ensure protection of your data, Storage Mirroring offers multi-level security using native operating system security features. Privileges are granted through membership in user groups defined on each machine running Storage Mirroring. To gain access to a particular Storage Mirroring source or target, the user must provide a valid operating system user name and password and the specified user name must be a member of one of the Storage Mirroring security groups.
How Storage Mirroring Security Works 1. When any Storage Mirroring client machine attempts to access a source or target machine running on Windows, it will attempt to automatically logon to the source or target using the three methods below. The security credentials of the user currently logged into the Storage Mirroring client machine are sent to the Storage Mirroring source or target machine.
Clearing Maintained Security Credentials Management Console Options - Security The Management Console will maintain login security credentials. The Security tab allows you to clear the cached credentials Enable ClearCached Security Credenitals to clear the stored credentials. To remove cached credentials, follow these steps. 1. To access the credentials security option, select File, Options and select the Security tab. 2. To remove the security credentials, click Clear Cached Security Credentials. 3.
2. The selected account will need to have additional user rights granted to it. NOTE: 3. If domain-level policy settings are defined (through Domain Security Policy, Security Settings, Local Policies, User Rights Assignment), they will override local policy settings. a. Select Start, Programs, Administrative Tools, Local Security Policy. b. Expand the Local Policies folder and highlight the User Rights Assignment folder. c.
Storage Mirroring Groups Storage Mirroring requires two local groups on each source and target for security. During the installation process, these groups are automatically created. The groups are assigned specific case-sensitive names: Storage Mirroring Admin Storage Mirroring Monitors The local administrator and the domain administrator are automatically added to the Storage Mirroring Admin group.
Windows Active Directory Active Directory, a central component of Windows 200x, manages information about the resources in a networking environment. The Storage Mirroring service automatically registers with Active Directory when the service starts. Storage Mirroring servers on the network can be located by the Storage Mirroring heartbeats, by Active Directory, or both.
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Index A activation code 20-3 Active Directory 22-6 add-ons activation code 20-3 overview 2-6 alternate data streams 13-2 Application Manager 2-6 audience 1-1 B bandwidth limitations 15-5 block target paths 14-26, 20-10 C centralized backup 2-1 chained configuration 2-13 client logs 20-13 cluster configuration 10-1 connection 10-1 failover configuration 16-2 Source Connection resource 10-6 compression 14-11 configurations 2-9 connection automatic reconnections 14-25 choosing connection type 5-1 cluster 10-
O one-to-many configuration 2-12 one-to-one configuration 2-9, 2-10 orphan files 14-12 overview operations 2-2 product 2-1 P Performance Monitor 19-30 ports Failover Control Center 4-7 overview 11-1 server 20-5 Q queuing 14-22, 14-23, 20-6 R recovering entire server 6-3 Recovery Manager command line 6-8 optional settings 6-6 overview 4-8 recovering 6-3 saving configuration options 4-8 snapshots 6-7 refresh rate 4-7 reparse points 13-2 replication capabilities 13-2 overview 2-3 starting 14-10 replication