Hitachi Dynamic Link Manager Software Users Guide for AIX
Table Of Contents
- (for AIX) User Guide
- Contents
- Preface
- Overview of HDLM
- HDLM Functions
- Devices Managed by HDLM
- System Configuration
- LU Configuration
- Program Configuration
- Position of the HDLM Driver and hdisk
- Distributing a Load Using Load Balancing
- Performing Failovers and Failbacks Using Path Switching
- Monitoring intermittent errors (functionality when automatic failback is used)
- Detecting errors by using path health checking
- Distributing a Load by Using the Dynamic I/O Path Control Function
- Error management
- Collecting Audit Log Data
- Integrated HDLM management using Global Link Manager
- Cluster support
- Creating an HDLM Environment
- HDLM System Requirements
- Flow for Creating an HDLM Environment
- Types of HDLM Installation
- Notes on Creating an HDLM Environment
- Notes on Installing HDLM
- Notes on an Upgrade Installation or Re-installation of HDLM
- Notes on the Virtual I/O Server
- Notes on the License Key and License Key File
- Notes on Trace Files
- Notes on Storage Systems
- Notes on the Cluster
- Notes on the Automatic Failback
- Notes on the queue_depth Parameter Value for an HDLM-Managed device
- Installing HDLM
- Available Installation Methods
- Preparations for a New Installation of HDLM
- Performing a New Installation of HDLM
- Preparations for an Upgrade Installation or Re-installation of HDLM
- Performing an Upgrade Installation or Re-installation of HDLM
- Installing HDLM to the SPOT of a NIM resource
- Migrating from HDLM Version 5.8.1 or Earlier to Version 5.9 or Later
- Installing HDLM in a PowerHA 6.1 Environment
- Installing HDLM in an Environment Running PowerHA 7.1 or a Later Version
- Performing an Unattended Installation of HDLM
- Checking the Path Configuration
- Setting up HDLM
- Setting up Integrated Traces
- Notes on Using the Hitachi Network Objectplaza Trace Library
- Displaying the Hitachi Network Objectplaza Trace Library setup menu
- Changing the Size of Integrated Trace Files
- Changing the Number of Integrated Trace Files
- Changing the Buffer Size Per Monitoring Interval Duration
- Adjusting the Number of Messages to be Output Per Monitoring Interval
- Finishing the Hitachi Network Objectplaza Trace Library Settings
- Applying the Hitachi Network Objectplaza Trace Library Settings
- About the Reservation Policy
- Settings for Using PowerHA
- Settings for Using GPFS
- Settings for Using Oracle RAC 10g or Oracle RAC 11g
- Settings for Using VCS
- Removing HDLM
- HDLM Operation
- Notes on Using HDLM
- Displaying Path Information
- When a Path Error Is Detected
- Storage System
- Notes on Shutting Down a Host
- Notes on Errors in a Host
- Notes on Enabling Both Primary and Secondary Volumes to Be Viewed From the Same Server
- Notes on an LVM Mirror Configuration
- Notes on When the OS Functionality in Not Available in a Boot Disk Environment
- Notes on Replicating a System
- HDLM Operations Using Commands
- Notes on Using Commands
- Viewing Path Information
- Changing the Status of Paths
- Viewing LU Information
- Displaying the Correspondences Between hdisks, OS Management Path IDs, and LDEVs
- Initializing Statistical Information for Paths
- Viewing and Setting Up the Operating Environment
- Viewing License Information
- Updating the License
- Viewing HDLM Version Information
- Viewing HDLM Component Information
- Starting and Stopping the HDLM Manager
- HDLM Resident Processes
- Changing the Configuration of the HDLM Operating Environment
- Notes on Using HDLM
- Troubleshooting
- Command Reference
- Overview of the HDLM Command dlnkmgr
- clear (Returns the Path Statistics to the Initial Value)
- help (Displays the Operation Format)
- offline (Places Paths Offline)
- online (Places Paths Online)
- set (Sets Up the Operating Environment)
- view (Displays Information)
- add (Adds a Path Dynamically)
- delete (Deletes a Path Dynamically)
- Utility Reference
- Overview of the Utilities
- DLMgetras Utility for Collecting HDLM Error Information
- dlmchpdattr Utility for Changing HDLM Default Settings
- dlmgetrasinst Utility for Collecting HDLM Installation Error Information
- dlminstcomp Utility for HDLM Component Installation
- dlmmigsts Utility for Assisting HDLM Migration
- dlmodmset Utility for Setting the HDLM Execution Environment ODM
- dlmpostrestore Utility for HDLM Restoration Support
- dlmpr Utility for Clearing HDLM Persistent Reservation
- dlmpremkcd Utility for Preparing for a System Backup
- dlmpreremove Utility for Executed Before Removing HDLM
- dlmrmdev Utility for Deleting HDLM Drivers
- dlmrmprshkey Utility for Clearing HDLM Persistent Reservation (Shared-Host Methodology)
- installhdlm Utility for Installing HDLM
- installux.sh Utility for HDLM Common Installer
- Messages
- Before Viewing the List of Messages
- KAPL01001 to KAPL02000
- KAPL03001 to KAPL04000
- KAPL04001 to KAPL05000
- KAPL05001 to KAPL06000
- KAPL06001 to KAPL07000
- KAPL07001 to KAPL08000
- KAPL08001 to KAPL09000
- KAPL09001 to KAPL10000
- KAPL10001 to KAPL11000
- KAPL11001 to KAPL12000
- KAPL13001 to KAPL14000
- KAPL15001 to KAPL16000
- Return Codes for Hitachi Command Suite Common Agent Component
- Functional Differences Between Versions of HDLM
- Differences Between HDLM Version 5.9 or Later and Version 5.8.1 or Earlier
- Add-in HDLM Driver Module
- Simplifying the HDLM Environment Configuration and Operation Procedures by Changes to the Logical Device Files
- Changing the HDLM Environment Configuration and Operation Procedures by Changes to the Logical Device Files
- Migrating Reservation Control Settings
- Support for a Boot Disk Environment
- About Settings when Upgrading the OS
- Changing a Virtual I/O Server's Method of Recognizing Virtual SCSI Disks
- Acronyms and abbreviations
- Glossary
- Index
¢
Virtual Storage Platform series
¢
VSP G1000 series
¢
Hitachi AMS2000 series
#
¢
Hitachi SMS series
#
¢
HUS100 series
#
¢
HUS VM
#: This storage system applies when the dynamic I/O path control
function is disabled.
Load Balancing Algorithms
HDLM has the following six load balancing algorithms:
• The Round Robin algorithm
• The Extended Round Robin algorithm
• The Least I/Os algorithm
• The Extended Least I/Os algorithm
• The Least Blocks algorithm
• The Extended Least Blocks algorithm
The above algorithms are divided into two categories, which differ in their
processing method. The following describes both of these processing
methods:
The Round Robin, Least I/Os, and Least Blocks algorithms
These algorithms select which path to use every time a certain number of
I/Os are issued. The path that is used is determined by the following:
¢
Round Robin
The paths are simply selected in order from among all the connected
paths.
¢
Least I/Os
The path that has the least number of I/Os being processed is
selected from among all the connected paths.
¢
Least Blocks
The path that has the least number of I/O blocks being processed is
selected from among all the connected paths.
The Extended Round Robin, Extended Least I/Os, and Extended Least Blocks
algorithms
These algorithms determine which path to allocate based on whether the
data of the I/O to be issued is sequential with the data of the I/O that
was issued immediately beforehand.
If the data is sequential, the path used will be the one to which the data
of the I/O that was issued immediately beforehand was distributed.
However, if a specified number of I/Os has been issued to a path,
processing switches to the next path.
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HDLM Functions
Hitachi Dynamic Link Manager (for AIX) User Guide