Veritas™ Volume Manager Administrator's Guide
- Understanding Veritas Volume Manager
- VxVM and the operating system
- How VxVM handles storage management
- Volume layouts in VxVM
- Online relayout
- Volume resynchronization
- Dirty region logging
- Volume snapshots
- FastResync
- Provisioning new usable storage
- Administering disks
- Disk devices
- Discovering and configuring newly added disk devices
- Discovering disks and dynamically adding disk arrays
- How to administer the Device Discovery Layer
- Changing the disk-naming scheme
- Adding a disk to VxVM
- Rootability
- Displaying disk information
- Removing disks
- Removing and replacing disks
- Administering Dynamic Multi-Pathing
- How DMP works
- Administering DMP using vxdmpadm
- Gathering and displaying I/O statistics
- Specifying the I/O policy
- Online dynamic reconfiguration
- Reconfiguring a LUN online that is under DMP control
- Creating and administering disk groups
- About disk groups
- Displaying disk group information
- Creating a disk group
- Importing a disk group
- Moving disk groups between systems
- Handling cloned disks with duplicated identifiers
- Handling conflicting configuration copies
- Reorganizing the contents of disk groups
- Destroying a disk group
- Creating and administering subdisks and plexes
- Displaying plex information
- Reattaching plexes
- Creating volumes
- Types of volume layouts
- Creating a volume
- Using vxassist
- Creating a volume on specific disks
- Creating a mirrored volume
- Creating a striped volume
- Creating a volume using vxmake
- Initializing and starting a volume
- Using rules and persistent attributes to make volume allocation more efficient
- Administering volumes
- Displaying volume information
- Monitoring and controlling tasks
- Reclamation of storage on thin reclamation arrays
- Stopping a volume
- Resizing a volume
- Adding a mirror to a volume
- Preparing a volume for DRL and instant snapshots
- Adding traditional DRL logging to a mirrored volume
- Enabling FastResync on a volume
- Performing online relayout
- Adding a RAID-5 log
- Creating and administering volume sets
- Configuring off-host processing
- Administering hot-relocation
- How hot-relocation works
- Moving relocated subdisks
- Administering cluster functionality (CVM)
- Overview of clustering
- Multiple host failover configurations
- CVM initialization and configuration
- Dirty region logging in cluster environments
- Administering VxVM in cluster environments
- Changing the CVM master manually
- Importing disk groups as shared
- Administering sites and remote mirrors
- About sites and remote mirrors
- Fire drill - testing the configuration
- Changing the site name
- Administering the Remote Mirror configuration
- Failure and recovery scenarios
- Performance monitoring and tuning
- Appendix A. Using Veritas Volume Manager commands
- Appendix B. Configuring Veritas Volume Manager
Getting or setting the iSCSI operational parameters
DDL provides an interface to set and display certain parameters that affect the performance of the iSCSI device path. However, the underlying OS framework must support the ability to set these values. The vxddladm set command returns an error if the OS support is not available.
Table: Parameters for iSCSI devices
Parameter | Default value | Minimum value | Maximum value | ||
---|---|---|---|---|---|
DataPDUInOrder | yes | no | yes | ||
DataSequenceInOrder | yes | no | yes | ||
DefaultTime2Retain | 20 | 0 | 3600 | ||
DefaultTime2Wait | 2 | 0 | 3600 | ||
ErrorRecoveryLevel | 0 | 0 | 2 | ||
FirstBurstLength | 65535 | 512 | 16777215 | ||
InitialR2T | yes | no | yes | ||
ImmediateData | yes | no | yes | ||
MaxBurstLength | 262144 | 512 | 16777215 | ||
MaxConnections | 1 | 1 | 65535 | ||
MaxOutStandingR2T | 1 | 1 | 65535 | ||
MaxRecvDataSegmentLength | 8182 | 512 | 16777215 |
To get the iSCSI operational parameters on the initiator for a specific iSCSI target
- Type the following commands:
# vxddladm getiscsi target=tgt-id {all | parameter}
You can use this command to obtain all the iSCSI operational parameters. The following is a sample output:
# vxddladm getiscsi target=c2_p2_t0
PARAMETER CURRENT DEFAULT MIN MAX ------------------------------------------------------------------------------ DataPDUInOrder yes yes no yes DataSequenceInOrder yes yes no yes DefaultTime2Retain 20 20 0 3600 DefaultTime2Wait 2 2 0 3600 ErrorRecoveryLevel 0 0 0 2 FirstBurstLength 65535 65535 512 16777215 InitialR2T yes yes no yes ImmediateData yes yes no yes MaxBurstLength 262144 262144 512 16777215 MaxConnections 1 1 1 65535 MaxOutStandingR2T 1 1 1 65535 MaxRecvDataSegmentLength 8192 8182 512 16777215
To set the iSCSI operational parameters on the initiator for a specific iSCSI target
- Type the following command:
# vxddladm setiscsi target=tgt-id parameter=value