HP StoreOnce Backup systems Concepts and Configuration Guidelines Abstract If you are new to the HP StoreOnce Backup System, read this guide before you configure your system.
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Contents 1 Before you start..........................................................................................7 Overview................................................................................................................................7 HP StoreOnce Backup system models..........................................................................................7 StoreOnce Catalyst targets for backup applications.......................................................................
Template 5, uses 1GbE network only....................................................................................40 6 Fibre Channel considerations.....................................................................41 Port assignment for StoreOnce Backup systems with two Fibre Channel cards..................................41 General Fibre Channel configuration guidelines..........................................................................42 Switched fabric........................................
Maximum number of hosts per NFS share ............................................................................72 CIFS share authentication....................................................................................................72 Backup application configuration..............................................................................................72 Backup file size..................................................................................................................
VTL and NAS device types................................................................................................111 HP StoreOnce Optimum Configuration for Tape Offload............................................................112 Offload Considerations.........................................................................................................112 VTL Cloning/Media Copy to Physical Tape.........................................................................
1 Before you start Overview The HP StoreOnce Backup System is a disk-based storage appliance for backing up host network servers or PCs to target devices on the appliance. These devices are configured as Network-Attached Storage (NAS), StoreOnce Catalyst or Virtual Tape Library (VTL) targets for backup applications. The total number of backup target devices provided by an HP StoreOnce Backup System varies according to model.
Table 2 StoreOnce 2700/ 4500, 4700 (continued) Product model Description Interfaces supported HP StoreOnce 4700 24TB Backup, BB879A A head server unit with two 1TB disks and a pre-configured storage array with twelve 2TB disks iSCSI and FC HP StoreOnce 4900 48TB Backup, BB903A A head server unit iSCSI and FC with two 1TB disks and a pre-configured two-drawer disk enclosure with eleven 4TB disks and four hot spare disks Ports Storage expansion 4 x 1GbE ports 2 x 10GbE ports 4 x FC ports Up to seve
For supported Symantec backup products, a plug-in application (HP OST 2.0) is required on each backup application media server that will use the Catalyst functionality. This can be downloaded from the Software Storage section of your StoreOnce product's Download drivers and software page on http://www.hp.com/support/downloads. OST/Catalyst devices require a license to be used at both source and target – but do NOT require an additional Catalyst Copy license as well.
Table 4 Comparing StoreOnce Catalyst, NAS and Virtual Tape device types Device Type Key Features Virtual Tape (VTL) Uses virtual tape drives and Enterprise FC SAN virtual slots to emulate environment (some models physical tape libraries do not support FC).
Table 5 Single node systems, ethernet and FC ports (continued) Product/Model Name Product Number StoreOnce 4220 BB855A Ethernet Connection Fibre Channel Connection 2 x 1GbE 2 x 8GB FC nl StoreOnce 4420 BB856A 2 x 1GbE 2 x 10GbE 2 x 8GB FC 2 x 1GbE 2 x 10GbE 2 x 8GB FC nl StoreOnce 4430 BB857A nl For multi-node systems, the number of network and FC ports depends upon the number of couplets and racks installed. There is a minimum of one couplet and one rack.
Types of licensing There are two types of licensing: • Full license (not time limited) • Instant on (time limited to 90 days): This allows you to try out licensable functionality on StoreOnce hardware products before paying for a full license for features such as Replication Target, Catalyst, or the Security features of Data at Rest Encryption and Secure Erase.
NOTE: If you need to immediately remove data, you must make sure your backup application is configured correctly. Rotation and retention policies may need to be revisited to ensure that the data is expired. Also, data that has been written to a store or library without secure erase enabled will not be able to be securely erased (there is no retroactive application of secure erase to already written data). Only chunks that are not referenced by any other items can be securely erased.
2 HP StoreOnce technology A basic understanding of the way that HP StoreOnce Technology works is necessary in order to understand factors that may impact performance of the overall system and to ensure optimal performance of your backup solution. Data deduplication HP StoreOnce Technology is an “inline” data deduplication process. It uses hash-based chunking technology, which analyzes incoming backup data in “chunks” that average 4K in size.
VTL and NAS Replication overview Deduplication technology is the key enabling technology for efficient replication because only the new data created at the source site needs to replicate to the target site once seeding is complete. This efficiency in understanding precisely which data needs to replicate can result in bandwidth savings in excess of 95% compared to having to transmit the full contents of a cartridge/share from the source site.
reclamation). The process of removing chunks of data is not an inline operation because this would significantly impact performance. This process, termed “housekeeping”, runs on the appliance as a background operation. Housekeeping is triggered in different ways depending on device type and backup application: • VTL: media on which the data retention period has expired will be overwritten by the backup application. The act of overwriting triggers the housekeeping of the expired data.
The figure below shows a single backup job from multiple hosts, where the backup data is radically different from one backup job to the next. There is also only a single stream to the device on the StoreOnce Backup system. This configuration produces slow performance and poor deduplication ratios.
Figure 2 Recommended configuration using multiple streams Effect of multiple streams on StoreOnce Performance The following graph, illustrates the relationship between the number of active data streams and performance; the appliance is assumed to be one of the larger models where more than 24 streams (if fast enough) can achieve best throughput. The throughput values shown are for example only. Along the x axis is the number of concurrent streams.
Figure 3 Relationship between active data streams and device configuration ( VTLs shown) Note 1: Stream source data rates will vary; some streams will be at 8, others at 50, and maybe some others at 200. This means that as the stream count increases, it will be the aggregate total of the streams that will drive the unit to saturation, which is the goal.
ingest of the StoreOnce appliance is 600MB/sec but we can only achieve 500 MB/sec because that is as fast we we can supply the data (because of stream limitations). If we could re-configure the backups to provide more streams, we could get higher throughput. In example 4 (brown circle) we show a more realistic situation where we have a mixture of different hosts with different performance levels.
we could configure 6 devices with say 17 streams to each or 20 devices with 5 streams to each.
3 Concepts specific to StoreOnce B6200 Backup system The HP B6200 Backup system provides up to 8 separate nodes in a single appliance with a single management GUI for all nodes, and failover capability across nodes within the same couplet as standard. The best practices for single-node StoreOnce Backup systems apply but significant thought must also be given to mapping customer backup requirements and media servers across devices located on up to 8 separate nodes.
B6200 Basic Concepts Figure 6 HP StoreOnce B6200, basic concepts The above diagram shows the basic concepts of the HP B6200 StoreOnce architecture – understanding the architecture is key to successful deployment. • Node: This is the basic physical building block and consists of an individual server (HP Proliant server hardware) • Couplet: This consists of two associated nodes and is the core of the failover architecture.
not use LACP (Link Aggregation Control Protocol) so there are no specific network switch settings required. • Storage shelf: This refers to the P2000 master controller shelf (one per node) or a P2000 JBOD capacity upgrade. JBODs are purchased in pairs and up to three pairs may be added to each couplet. They use dual 6Gbps SAS connections for resilience. In reality, up to 128 TB of storage is shared between two nodes in a couplet.
Figure 8 Showing Node 2, Service Set 2 failed over to Node 1 Deployment choices The very first deployment choice is how to use the external networking and Fibre Channel connections that the B6200 Enterprise StoreOnce Backup System presents. • All GbE network connections are for NAS devices, replication and device management, and are bonded pairs to provide resiliency. There are 2 x 10 GbE ports and 4 x 1GbE ports on each node.
Figure 9 HP B6200 Backup system, customer connections 26 Concepts specific to StoreOnce B6200 Backup system
4 Networking considerations The network configuration for the StoreOnce single node systems and the StoreOnce multi node systems has some significant differences. Since the StoreOnce multi node product supports autonomic failover, more care is required in the network configuration to ensure optimal operation of the autonomic failover feature. The network configuration is done as part of the HP installation process for the multi node system.
• For the HP B6200 Backup system, networking parameters are specified within the selected network template. • All StoreOnce Backup systems have two 1GbE ethernet ports. Most also have two additional 10GbE ports. Network bonding is supported on pairs of 1GbE and 10GbE ports, as described in the next section. Network bonding modes Each pair of network ports on the appliance can be configured either on separate subnets or in a bond with each other (1GbE and 10GbE ports cannot be bonded together).
General guidelines Single node StoreOnce appliances have a factory default network configuration where the first 1GbE port (Port 1 /eth0) is enabled in DHCP mode. This enables quick access to the StoreOnce CLI and Management GUI for customers using networks with DHCP servers and DNS lookup because the appliance hostname is printed on a label on the appliance itself. The default bonding mode is Mode 1. Mode 6 bonding provides port failover and load balancing across the physical ports.
Single port configurations The example shows the simplest configuration of a single subnet containing just one 1GbE network port, generally this configuration is likely to be used: • Only if the network interface is required only for management of the appliance or • Only if low performance and resiliency backup and restore are acceptable. A single 10GbE port could also be configured in this way (on 4420/4430 appliances), providing both a backup data interface and management interface.
Dual port configurations This example describes configuring multiple subnets in separate IP address ranges for each pair of network ports. A maximum of 4 separate subnets can be configured on a StoreOnce 4420 or 4430 appliance (2 x 1GbE and 2 x 10GbE). Use this mode: • If servers to be backed up are split across two physical networks which need independent access to the appliance.
Bonded port configurations (recommended) If two network ports are configured within the same subnet they will be presented on a single IP address and will be bonded using one of the bonding modes as described in Network bonding modes. This configuration is generally recommended for backup data performance and also for resiliency of both data and management network connectivity.
10GbE Ethernet ports on StoreOnce Backup systems 10GbE Ethernet is provided as a viable alternative to the Fibre Channel interface for providing maximum iSCSI VTL performance and also comparable NAS performance. 10GbE ports also provide good performance when using StoreOnce Catalyst low and high bandwidth backup as well as Catalyst copy or VTL/NAS replication between appliances.
Option 1: HP StoreOnce Backup system on Corporate SAN and Network SAN In this option, the StoreOnce device has a port in the Corporate SAN which has access to the Active Directory Domain Controller. This link is then used to authenticate CIFS share access. The port(s) on the Network SAN are used to transfer the actual data. This configuration is relatively simple to configure: • On StoreOnce devices with only 1GbE ports: Two subnets should be configured with one port in each.
Option 2: HP StoreOnce Backup system on Network SAN only with Gateway In this option the StoreOnce appliance has connections only to the Network SAN, but there is a network router or Gateway server providing access to the Active Directory domain controller on the Corporate LAN. In order to ensure two-way communication between the Network SAN and Corporate LAN the subnet of the Network SAN should be a subnet of the Corporate LAN subnet.
5 Network configuration in multi-node StoreOnce Backup systems The multi-node StoreOnce B6200 Backup system has specific networking considerations to ensure support for autonomic failover. Installation and configuration of these systems is normally carried out by HP service specialists.
The optimum configuration is to use the 10GbE ports for data (NAS shares and Catalyst stores) and all replication traffic, and the 1GbE ports for the B6000 Management Console. However, this requires two sub-nets and may not be available to all users. Five network configurations are supported and configured using one of the supplied network templates, illustrated on the following pages. You must decide which template you intend to use prior to installation.
The default bonding mode for this template is Mode 1, Active/Backup, on both sub-nets. The recommended IP address range is 25 in total: 16 contiguous on the data sub-net; 1 + 8 contiguous on the management sub-net. NOTE: When using a 10GbE network, you must provide the correct SFPs for your environment. They are not supplied with the product.
Template 3, uses 10GbE network only Template 3 supports users who have a 10GbE network only. The same network is used for data and management. The default bonding mode for this template is Mode 1, Active/Backup. The recommended IP address range is 17 in total: 1 for management and 16 contiguous for data. NOTE: When using a 10GbE network, you must provide the correct SFPs for your environment. They are not supplied with the product.
Template 5, uses 1GbE network only For software revision 3.3.0 and greater: Template 5 supports users who want to have only two 1GbE network connections from each node in a couplet to their Ethernet switches. The same network is used for data and management. It is primarily for customers who only use VTL as their backup targets and do not use StoreOnce Catalyst stores or NAS CIFS/NFS shares. VTL replication jobs will still run over the Ethernet connections.
6 Fibre Channel considerations The HP StoreOnce B6200 Backup system supports switched fabric using NPIV only. All other HP StoreOnce Backup systems support both switched fabric and direct attach (private loop) topologies. Switched fabric using NPIV (N Port ID Virtualisation) offers a number of advantages and is the preferred topology for all StoreOnce appliances. NOTE: As with networking the multi-node StoreOnce B6200 Backup system has specific FC considerations to ensure support for autonomic failover.
General Fibre Channel configuration guidelines NOTE: The illustrations in this section show single node products (HP StoreOnce 4500, 4700, 4210 and 4220, and 4420 and 4430). Additional configuration requirements apply with the HP StoreOnce B6200 Backup system to support autonomic failover. For examples that illustrate multi node products (HP StoreOnce B6200) see Configuring FC to support failover with the HP StoreOnce B6200 Backup system.
The illustration above shows the flexibility of the configuration • VTL1 is connected to FC Port 1 exclusively • VTL3 is connected to FC Port 2 exclusively • VTL2 is spread across FC Port 1 and FC Port 2. The medium changer is connected to both ports whereas the drives by default are connected 50% to each port (2 each in this case).
Direct Attach (private loop) A direct attach (private loop) topology is implemented by connecting the StoreOnce appliance ports directly to a Host Bus Adapter (HBA). In this configuration the Fibre Channel private loop protocol must be used. NOTE: The HP StoreOnce B6200 Backup system is not supported in direct attach configurations.
Zoning may not always be required for configurations that are already small or simple. Typically the larger the SAN, the more zoning is needed. Use the following guidelines to determine how and when to use zoning. • Small fabric (16 ports or less)—may not need zoning • Small to medium fabric (16 - 128 ports)—use host-centric zoning. Host-centric zoning is implemented by creating a specific zone for each server or host, and adding only those storage elements to be utilized by that host.
Use the StoreOnce Management GUI to find out the WWPN for use in zoning. The WW port names are on the VTL-Libraries-Interface Information tab. Diagnostic Fibre Channel devices For each StoreOnce FC port there is a Diagnostic Fibre Channel Device presented to the Fabric. There will be one per active FC physical port. This means there are two per HP StoreOnce Backup system or node that has two Fibre Channel ports.
7 Configuring FC to support failover in a StoreOnce B6200 Backup system environment Autonomic failover Autonomic failover is a unique enterprise class feature of the HP B6200 StoreOnce Backup system. When integrated with various backup applications it makes it possible for the backup process to continue even if a node within a B6200 couplet fails. ISV scripts are usually required to complete this process. The failover process is best visualized by watching the video on: http:// www.youtube.
Failover support with backup applications Backup applications do not have an awareness of advanced features such as autonomic failover because they are designed for use with physical tape libraries and NAS storage. From the perspective of the backup application, when failover occurs, the virtual tape libraries and the NAS shares on the HP B6200 Backup System go offline and after a period of time they come back online again.
Designing for failover One node is effectively doing the work of two nodes in the failed over condition. There is some performance degradation but the backup jobs will continue after the autonomic failover. The following best practices apply when designing for autonomic failover support: • The customer must choose whether SLAs will remain the same after failover as they did before failover. If they do, the solution must be sized in advance to only use up to 50% of the available performance.
• In a dual fabric configuration ensure the equivalent FC ports from each B6200 node in a couplet are presented to the same fabric. However, they should present to separate switches within the fabric. See Scenario 3. • Ensure the D2D diagnostic device WWNs (these will be seen in the switch name server and are associated with the physical ports) are not included in any fabric zones and, therefore, not presented to any hosts.
Figure 25 VTL FC example port configurations Fibre channel port presentations 51
Scenario 1, single fabric with dual switches, recommended Figure 40 illustrates the logical connectivity between the hosts and the VTLs and their FC ports. The arrows illustrate accessibility, not data flow.
If FC switch1 fails, Host A and Host B lose access to their backup devices. Hosts C and D still have access to the media changers and to 50% of the drives on VTL2 and 50% of the drives on VTL1 B6200 failover between nodes is enabled. Scenario 2, single fabric with dual switches, not advised The FC configuration is the same in this scenario, but the VTLs are presented to a single port. This configuration is not advised because it compromises the B6200 autonomic failover facility.
If FC switch1 fails, Host A and Host B lose access to their backup devices, even though B6200 failover is enabled because the physical configuration provides a point of failure. Hosts C and D still have access to the media changers and to 100% of the drives on VTL3 and VTL4. Scenario 3, dual fabric with dual switches, recommended This FC configuration has added complexity because it has two fabrics. The arrows illustrate accessibility, not data flow.
What happens if a fabric fails? If Fabric 1 fails in the previous configuration, all VTL libraries and nodes on the HP B6200 Backup System still have access to Fabric 2. As long as Hosts A, B and C also have access to Fabric 2, then all backup devices are still available to Hosts A, B and C. The following diagram illustrates existing good paths after a fabric fails.
Figure 30 Complex configuration with ports of different VTLs being presented to different fabrics, Fabric 2 fails Scenario 4, dual fabric with dual switches, not advised The FC configuration is the same as scenario 3, but the VTLs are presented to a single port, which means they are tied to a single switch within a single fabric. This configuration is not advised because it compromises the B6200 autonomic failover facility.
Figure 31 Complex configuration with ports of different VTLs being presented to different fabrics, not advised Scenario 4, dual fabric with dual switches, not advised 57
8 StoreOnce Catalyst stores StoreOnce Catalyst technology HP StoreOnce Catalyst delivers a single, integrated, enterprise-wide deduplication algorithm. It allows the seamless movement of deduplicated data across the enterprise to other StoreOnce Catalyst systems without rehydration.
• HP StoreOnce Catalyst is an additional licensable feature both on the StoreOnce appliance and within the backup software because of the advanced functionality it delivers. • HP StoreOnce is only supported on HP Data Protector 7.01, Symantec NetBackup 7.x and Symantec Backup Exec 2012.
The deduplication offload into the media server is implemented in different ways in different backup applications. • With HP Data Protector the StoreOnce deduplication engine is embedded in the HP Data Protector Media Agent that talks to the Catalyst API. • In Symantec products HP has developed an OpenStorage (OST) Plug-in to NetBackup and Backup Exec that creates the interface between Symantec products and the StoreOnce Catalyst store API.
Figure 33 Catalyst copy models Summary of Catalyst best practices HP StoreOnce Catalyst is a unique interface and is fundamentally different from virtual tape or NAS. It provides the backup application with full control of backup and replication (called Catalyst Copy). For this reason, best practices are dependent upon the backup application.
• Ensure the backup clean-up scripts that regularly check for expired Catalyst Items run at a frequency that avoids using excessive storage to hold expired backups (every 24 hours is recommended). • There are several specific tuning parameters dependent on backup application implementation – please see separate document for more details..
Figure 36 StoreOnce Catalyst Bandwidth limiting Client access permissions Catalyst stores have a process that allows client access to the Catalyst stores to be controlled. First overall client access permission checking is enabled from the StoreOnce Catalyst – Settings tab. Figure 37 Enabling client access permission checking Then each Catalyst store has a list of clients defined who are allowed to access it from the StoreOnce Catalyst – Stores – Permissions tab.
Figure 38 Setting access permissions for a store More information HP StoreOnce Catalyst is a unique interface and is fundamentally different from virtual tape or NAS. It provides the backup application with full control of backup and replication (called Catalyst Copy). For this reason, best practices and configuration are dependent upon the backup application.
9 Virtual Tape Devices Overview Virtual Tape Devices are backup target devices on the HP StoreOnce Backup system to which the backup application on the hosts write data. They appear to the host as a locally-attached physical tape library, but physically, they use disk space on the HP StoreOnce Backup system which, as in tape terminology, is referred to as slots or cartridges. Tape Libraries provide considerable storage capacity and full support for tape rotation strategies.
(which may include the library device). The same limitation could be hit with multiple libraries and fewer drives per library. • A similar limitation exists for Fibre Channel. Although there is a theoretical limit of 255 devices per FC port on a host or switch, the actual limit appears to be 128 for many switches and HBAs. You should either balance drives across FC ports or configure less than 128 drives per library.
implementation, by default, does not allow block sizes that are greater than 256 KB. To use a block size greater than this you need to modify the following registry setting: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\ nl nl nl {4D36E97B-E325-11CE-BFC1-08002BE10318}\0000\Parameters Change the REG_DWORD MaxTransferLength to “80000” hex (524,288 bytes), and restart the media server – this will restart the iSCSI initiator with the new value.
Figure 39 Cartridges with appended backups (not recommended) Our recommendations are: • Target full backup jobs to specific cartridges, sized appropriately • Reduce the number of appends by specifying separate cartridges for each incremental backup Taking the above factors into consideration, an example of a good rotation scheme where the customer requires weekly full backups sent offsite and a recovery point objective of every day in the last week, every week in the last month, every month in the last
• Tape drive emulation types have no effect on performance or functionality • Configuring multiple tape drives per library enables multi-streaming operations per library for good aggregate throughput performance. • Do not exceed the recommended maximum concurrent backup streams per library and appliance if maximum performance is required. • Target the backup jobs to run simultaneously across multiple drives within the library and across multiple libraries.
10 NAS shares NOTE: It is important to understand that the HP StoreOnce network share is intended to be used ONLY by backup applications that “back up to disk”. Do not use the NAS target device as a drag-and-drop general file store. The one exception to this rule is if you are using the NAS share to seed an appliance for replication.
Maximum concurrently open files The table in Key parameters (page 115) shows the maximum number of concurrently open files per share and per StoreOnce appliance for files above and below the 24 MB dedupe threshold size. A backup job may consist of several small metadata/control files (that are constantly being updated) and at least one large data file. In some cases, backup applications will hold open more than one large file. It is important not to exceed the maximum concurrent backup operations.
There are also limits on the number of open files greater than the deduplication threshold that are allowed per share and per appliance. These are the files that hold the backed-up data. Backup applications generally create a small number of additional files during a backup job in order to store configuration details and catalog entries. Some of these small files will generally be updated throughout the backup process and, in most instances, these files will be below the deduplication threshold.
When using a backup application with StoreOnce NAS shares the user will need to configure a new type of device in their backup application. Each application varies as to what it calls a backup device that is located on a StoreOnce device, for example it may be called a File Library, Backup to Disk Folder, or even Virtual Tape Library.
Disk space pre-allocation Some backup applications allow the user to choose whether to “pre-allocate” the disk space for each file at creation time, i.e. as soon as a backup file is created an empty file is created of the maximum size that the backup file can reach. This is done to ensure that there is enough disk space available to write the entire backup file.
Appended backups should not be used because there is no benefit to using the append model, this does not save on disk space used. Compression and encryption Most backup applications provide the option to compress the backup data in software before sending, this should not be implemented. Software compression will have the following negative impacts: 1. Consumption of system resources on the backup server and associated performance impact. 2.
• Each NAS share has a 25,000 file limit, some backup applications create large numbers of small control files during backup to disk. If this is the case , it may be necessary to create additional shares and distribute the backup across multiple shares. • Disable software compression, deduplication and synthetic full backups. • Do not pre-allocate disk space for backup files within the backup application.
11 Replication When considering replication you are likely to be synchronizing data between different models of HP StoreOnce Backup Systems. The examples in this section are not specific to a particular model of HP StoreOnce Backup System. Replication can take place between multi-node and single-node StoreOnce Backup Systems. The GUI for both refers to both Replication Targets and Sources as appliances.
StoreOnce VTL and NAS replication overview The StoreOnce Backup system utilizes a propriety protocol for replication traffic over the Ethernet ports; this protocol is optimized for deduplication-enabled replication traffic. An item (VTL Cartridge or NAS file) will be marked ready for replication as soon as it is closed (or the VTL cartridge returned to its slot).
Figure 40 Active to passive replication Figure 41 Active to active replication Replication usage models (VTL and NAS) 79
Figure 42 Many to Once replication 80 Replication
Figure 43 N-way replication In most cases StoreOnce VTL and StoreOnce NAS replication is the same, the only significant configuration difference being that VTL replication allows multiple source libraries to replicate into a single target library, NAS mappings however are 1:1, one replication target share may only receive data from a single replication source share. In both cases replication sources libraries or shares may only replicate into a single target.
by creating media pools with the backup application then manually assigning source library cartridges into the relevant pools.
between sites. In all reporting on the StoreOnce Management GUI, the throughput in MB/sec is apparent throughput – think of this at the rate at which we are apparently replicating the backup data between sites. What actually happens in replication? Assuming the seeding process is complete (seeding is when the initial data is transferred to the target device), the basic replication process works like this: 1. Source has a cartridge (VTL) or File (NAS) to replicate 2.
As a general rule of thumb, however, a minimum bandwidth of 2 Mb/s per replication job should be allowed. For example, if a replication target is capable of accepting 8 concurrent replication jobs (HP 4220) and there are enough concurrently running source jobs to reach that maximum, the WAN link needs to be able to provide 16 Mb/s to ensure that replication will run correctly at maximum efficiency – below this threshold replication jobs may begin to pause and restart due to link contention.
During the seeding process it is recommended that no other operations are taking place on the source StoreOnce Backup system, such as further backups or tape copies. It is also important to ensure that the StoreOnce Backup system has no failed disks and that RAID parity initialization is complete because these will impact performance.
Table 8 Summary of seeding methods and likely usage models (continued) Technique Best for Concerns Comments Backup application Tape offload/ copy from source and copy onto target Suitable for all replication models, especially where remote sites are large (intercontinental) distances apart. Well suited to target sites that plan to have a physical Tape archive as part of the final solution. Best suited for StoreOnce VTL deployments. Unlikely to be used when seeding HP StoreOnce B6200 Backup systems.
Replication blackout windows The replication process can be delayed from running using blackout windows that may be configured using the StoreOnce GUI. Up to two separate windows per day, which are at different times for each day of the week, may be configured. The best practice is to set a blackout window throughout the backup window so that replication does not interfere with backup operations. If tape copy operations are also scheduled, a blackout window for replication should also cover this time.
Figure 45 Replication bandwidth settings Source appliance permissions It is a good practice to use the Source Appliance Permissions functionality provided on the Replication - Partner Appliances tab to prevent malicious or accidental configuration of replication mappings from unknown or unauthorized source appliances. See the HP StoreOnce Backup system user guide for information on how to configure Source Appliance Permissions.
12 Seeding methods in more detail While the concepts described in this chapter apply to all HP StoreOnce Backup systems, the diagrams in this chapter illustrate single node systems only. There is a separate chapter that illustrates how to implement replication and seeding with the HP StoreOnce B6200 Backup system. Seeding over a WAN link With this seeding method the final replication set-up (mappings) can be established immediately.
In the active-active replication model, WAN seeding after the first backup at each location is, in fact, the first wholesale replication in each direction.
In the Many-to-One model, WAN seeding over the first backup is, in fact, the first wholesale replication from the many remote sites to the Target site. Care must be taken not to run too many replications simultaneously or the Target site may become overloaded. Stagger the seeding process from each remote site.
Co-location (seed over LAN) The following diagram illustrates co-location seeding from a remote site to Data Center, in an active/passive replication model. The initial backup and replication takes place at the remote site over the LAN. The StoreOnce appliance holding the replicated data is then transported to the Data Center. Figure 50 Co-location seeding in an Actve/Passive replication model 1. Initial backup 2. Replication over GbE link at remote site over LAN 3. Ship appliance to Data Center site 4.
The following diagram illustrates a many-to-one example. Figure 51 Co-location seeding in an Actve/Passive replication model 1. Initial backup at each remote site 2. Replication to Target StoreOnce appliance over GbE link at each remote site over LAN 3. Move Target StoreOnce appliance between remote sites 4. Finally take Target StoreOnce appliance to Data Center and repeat replication. site. 5.
Floating StoreOnce seeding In this model co-location takes place at many remote sites using a floating StoreOnce target. The StoreOnce target is transported between may sites and the taken to the Data Center. It is a useful model for large-in fan scenarios. Figure 52 Seeding using floating StoreOnce Backup system 1. Initial backup at each remote site 2. Replication to floating StoreOnce Target appliance over GbE link at each remote site over LAN 3.
1. Plan the final master replication mappings from sources to target that are required and document them. Use an appropriate naming convention e.g. SVTL1, SNASshare1, TVTL1, TNASshare1. 2. At each remote site perform a full system backup to the source StoreOnce appliance and then configure a 1:1 mapping relationship with the floating StoreOnce appliance ” e.g. SVTL1 on Remote Site A -> FTVTL1 on floating StoreOnce. FTVTL1 = floating target VTL1. 3.
Figure 53 Seeding using physical tape and backup application 1. Initial backup to StoreOnce appliance 2. Copy to tape(s) or a disk using backup application software on Media Server for NAS devices; only use simple drag and drop to portable disk This technique is not possible at Sites A & B unless a media server is present. 3. Ship tapes/disks to Data Center site. 4.
5. 6. 7. removable media has to be registered into the catalog/database of the media server at the data center site. Create devices on the StoreOnce Backup system at the data center site using an agreed convention e.g. TVTL1, TNASshare1. Discover these devices through the backup application so that the media server at the data center site has visibility of both the removable media devices AND the devices configured on the StoreOnce Backup system.
13 Implementing replication with the HP B6200 Backup system The main difference with the HP B6200 StoreOnce implementation is that replication is part of the service set. Each service set (associated to Node 1, Node 2, et cetera) can handle a maximum of 48 incoming concurrent replication jobs per node and can itself replicate OUT to up to 16 devices. If failover occurs, the replication load becomes incumbent on the remaining service set.
Figure 54 Using dedicated nodes for replication targets at the target site (Active/Passive replication) Active/Passive and Active/Active configurations 99
Figure 55 Using dedicated nodes for replication targets at the target site for Active Passive, along with backup sources at Site B 100 Implementing replication with the HP B6200 Backup system
In Figure 56 we deliberately provide one node on each couplet that is dedicated to replication. This simplifies the management, and the loading and performance is easier to predict. The way the couplets are balanced also means that wherever a node fails over we do not lose all our replication performance. In the failover scenario the remaining node can still handle backup in one time window and replication in another time window so the overall impact of a failed node is not that damaging.
Many to One configurations The other main usage model for the HP B6200 Backup system is in large-scale remote office deployments where a fan-in of up to 384 replication jobs to a maximum-configuration HP B6200 Backup System is possible (one stream per device). The sources (remote offices) are more likely to be single-node HP StoreOnce StoreOnce Backup systems. For a large number of remote sites co-location is impractical, instead the Floating StoreOnce option is recommended.
the necessary data is already seeded on the B6200 for Remote Site A and the synchronization process happens very quickly. In some scenarios where a customer has larger remote storage locations the floating StoreOnce process can be used together with the smaller locations seeding over the WAN link. Another consideration is the physical logistics for some customers with 100+ locations, some being international locations.
Figure 57 Balancing many-to-one replication sources across all available nodes Replication and load balancing The specification for a B6200 service set is that it can accept up to a maximum of 48 concurrent replication streams from external sources. If more than 48 streams are replicating into a B6200 node, some streams will be put on hold until a spare “replication slot” becomes available.
• FC SAN 1 with its larger number of hosts and capacities is spread over four nodes all with maximum storage capacity. There are at least eight streams per node to provide good throughput performance • All the NAS target backups have been grouped together on node 5 and 6 on 10GbE – these could be VMWare backups which generally require a backup to NAS target.
14 Housekeeping Housekeeping is the process whereby space is reclaimed and is best scheduled to occur in quiet periods when no backup or replication is taking place. If insufficient time is allocated to housekeeping, there is a risk that housekeeping jobs will stack up – effectively “hogging” capacity So, there are two factors to consider: • Is housekeeping interfering with performance, in which case you may wish to set blackout windows, when housekeeping will not occur, see below.
On the StoreOnce Management Interface go to the Housekeeping page; a series of graphs and a configuration capability is displayed. There are four tabs on the Housekeeping page: Overall, Libraries, Shares and StoreOnce Catalyst. The Overall tab shows the total housekeeping load on the appliance. The other tabs can be used to select the device type and monitor housekeeping load on individual named VTL, NAS shares or Catalyst stores.
has been running nonstop for a couple of hours), therefore if housekeeping is idle most of the time no information will be displayed. Figure 60 Housekeeping load graph 1. Housekeeping under control 2. Housekeeping out of control, not being reduced over time In the above graph we show two examples, one where the housekeeping load increases and then subsides, which is normal, and another where the housekeeping job continues to grow and grow overtime.
15 Tape Offload Terminology Direct Tape Offload This is when a physical tape library device is connected directly to the rear of the StoreOnce Backup system. This offload feature is not currently supported on HP StoreOnce Backup system. Backup application Tape Offload/Copy from StoreOnce Backup system This is the preferred way of moving data from a StoreOnce Backup system to physical tape.
Tape Offload/Copy from StoreOnce Backup system versus Mirrored Backup from Data Source A summary of the supported methods is shown below. Table 9 Tape Offload/Copy For easiest integration Backup application copy to tape nl For optimum performance Separate physical tape mirrored backup nl The backup application controls the copy from the StoreOnce appliance to the network-attached tape drive so that: This is a parallel activity. The host backs up to the StoreOnce appliance and the host backs up to tape.
Figure 61 StoreOnce Catalyst Copy offload to tape drive 1. Catalyst Copy command 2. Low bandwidth Catalyst Copy 3. Rehydration and full bandwidth copy to tape VTL and NAS device types Figure 62 Backup application tape offload at StoreOnce target site for VTL and NAS device types 1. Backup data written to StoreOnce Source 2. StoreOnce low bandwidth replication 3. All data stored safely at DR site.
Figure 63 Backup application tape offload at StoreOnce source site for VTL and NAS device types 1. Copy StoreOnce device to physical tape; this uses the backup Copy job to copy data from the StoreOnce appliance to physical tape and is easy to automate and schedule, it has a slower copy performance. 2. Mirrored backup; specific backup policy used to back up to StoreOnce and Physical Tape simultaneously (mirrored write) at certain times (monthly). This is a faster copy to tape method.
HP StoreEver Tape Libraries HP Half-Height Tape Drives for LTO 5 and LTO 6 have equal Data Transfer Rates to the Full-Height versions. This allows an HP StoreEver MSL 2024 to have two Half-Height LTO Drives with no decrease in performance giving maximum “performance density”.
HP MSL StoreOnce 4048 4420 & 3 Shelves 4 8 ESL G3 5 9 ESL G3 6 11 HP ESL G3 StoreOnce 4700 and 4430 6 12 ESL G3 7 14 ESL G3 8 15 HP ESL G3 StoreOnce 4700 and 4430 & 1 Shelf 6 12 ESL G3 7 14 ESL G3 8 15 HP ESL G3 StoreOnce 4700 and 4430 & 2 Shelves 6 12 ESL G3 7 14 ESL G3 8 8 HP ESL G3 StoreOnce 4700 and 4430 & 3 Shelves 6 12 ESL G3 7 14 ESL G3 8 8 NOTE: Split the number of data streams evenly between the physical drives.
16 Key parameters StoreOnce B6200 Backup Table 10 Key parameters for HP StoreOnce B6200 Backup StoreOnce Backup products running software 3.0.
Table 10 Key parameters for HP StoreOnce B6200 Backup (continued) StoreOnce Backup products running software 3.0.
Table 11 Key parameters for HP StoreOnce 2700, 4500 and 4700 Backup (continued) StoreOnce Backup products running software 3.8.0 and later StoreOnce 2700 StoreOnce 4500 StoreOnce 4700 Max VTL Drives Per Library/Appliance 32 96 200 Max Cartridge Size (TB) 3.2 3.2 3.
Table 12 Key parameters for HP StoreOnce 2610/2620, 4210/4220 and 4420/4430 Backup (continued) StoreOnce 2610 iSCSI StoreOnce 2620 iSCSI StoreOnce 4210 iSCSI/FC nl StoreOnce 4220 StoreOnce 4420 StoreOnce 4430 Max VTL Library Rep Fan In 1 1 8 8 16 16 Max Appliance Rep Fan Out 2 2 4 4 8 8 Max Appliance Rep Fan In 4 8 16 24 50 50 Max Appliance Concurrent Rep Jobs Source 12 12 24 24 48 48 Max Appliance Concurrent Rep Jobs Target 24 48 48 48 96 96 No No No No No No
Table 12 Key parameters for HP StoreOnce 2610/2620, 4210/4220 and 4420/4430 Backup (continued) StoreOnce 2610 iSCSI StoreOnce 2620 iSCSI StoreOnce 4210 iSCSI/FC nl StoreOnce 4220 StoreOnce 4420 StoreOnce 4430 Catalyst Command Sessions 16 16 32 32 64 64 Maximum Concurrent outbound copy jobs per appliance 12 48 24 24 48 48 Maximum Concurrent inbound data and copy jobs per appliance 12 48 96 96 192 192 StoreOnce Backup products running software 3.4.
About this guide This guide provides conceptual information about the following HP StoreOnce Backup systems: • HP StoreOnce B6200 Backup system • HP StoreOnce 2700 Backup system • HP StoreOnce 4500 Backup system • HP StoreOnce 4700 Backup system • HP StoreOnce 2620 Backup system • HP StoreOnce 4210/4220 Backup system • HP StoreOnce 4420/4430 Backup system Intended audience This guide is intended for users who install, operate and maintain the HP StoreOnce Backup System.
Table 13 Document conventions (continued) Convention Element Monospace text • File and directory names • System output • Code • Commands, their arguments, and argument values Monospace, italic text • Code variables • Command variables Monospace, bold text WARNING! CAUTION: IMPORTANT: NOTE: Emphasized monospace text Indicates that failure to follow directions could result in bodily harm or death. Indicates that failure to follow directions could result in damage to equipment or data.
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