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
Correcting conflicting configuration information
To resolve conflicting configuration information, you must decide which disk contains the correct version of the disk group configuration database. To assist you in doing this, you can run the vxsplitlines command to show the actual serial ID on each disk in the disk group and the serial ID that was expected from the configuration database. For each disk, the command also shows the vxdg command that you must run to select the configuration database copy on that disk as being the definitive copy to use for importing the disk group.
Note:
The disk group must have a version number of at least 110.
The following is sample output from running vxsplitlines on the disk group newdg:
# vxsplitlines -v -g newdg VxVM. vxsplitlines NOTICE V-0-0-0 There are 2 pools All the disks in the first pool have the same config copies All the disks in the second pool may not have the same config copies
To see the configuration copy from a disk, enter the following command:
# /etc/vx/diag.d/vxprivutil dumpconfig private path
To import the disk group with the configuration copy from a disk, enter the following command:
# /usr/sbin/vxdg (-s) -o selectcp=diskid import newdg
Pool 0 DEVICE DISK DISK ID DISK PRIVATE PATH newdg1 c2t5d0 1215378871.300.vm2850lx13 /dev/vx/rdmp/c2t5d0 newdg2 c2t6d0 1215378871.300.vm2850lx13 /dev/vx/rdmp/c2t6d0 Pool 1 DEVICE DISK DISK ID DISK PRIVATE PATH newdg3 c2t7d0 1215378871.294.vm2850lx13 /dev/vx/rdmp/c2t7d0
If you do not specify the -v option, the command has the following output:
# vxsplitlines -g mydg listssbinfo VxVM vxdg listssbinfo NOTICE V-0-0-0 There are 2 pools All the disks in the first pool have the same config copies All the disks in the second pool may not have the same config copies Number of disks in the first pool: 1 Number of disks in the second pool: 1
To import the disk group with the configuration copy from the first pool, enter the following command:
# /usr/sbin/vxdg (-s) -o selectcp=1221451925.395.vm2850lx13 import mydg
To import the disk group with the configuration copy from the second pool, enter the following command:
# /usr/sbin/vxdg (-s) -o selectcp=1221451927.401.vm2850lx13 import mydg
In this example, the disk group has four disks, and is split so that two disks appear to be on each side of the split.
You can specify the -c option to vxsplitlines to print detailed information about each of the disk IDs from the configuration copy on a disk specified by its disk access name:
# vxsplitlines -g newdg -c c2t6d0 DANAME(DMNAME) || Actual SSB || Expected SSB c2t5d0( c2t5d0 ) || 0.1 || 0.0 ssb ids don't match c2t6d0( c2t6d0 ) || 0.1 || 0.1 ssb ids match c2t7d0( c2t7d0 ) || 0.1 || 0.1 ssb ids match c2t8d0( c2t8d0 ) || 0.1 || 0.0 ssb ids don't match Please note that even though some disks ssb ids might match that does not necessarily mean that those disks' config copies have all the changes. From some other configuration copies, those disks' ssb ids might not match. To see the configuration from this disk, run /etc/vx/diag.d/vxprivutil dumpconfig /dev/vx/dmp/c2t6d0
Based on your knowledge of how the serial split brain condition came about, you must choose one disk's configuration to be used to import the disk group. For example, the following command imports the disk group using the configuration copy that is on side 0 of the split:
# /usr/sbin/vxdg -o selectcp=1045852127.32.olancha import newdg
When you have selected a preferred configuration copy, and the disk group has been imported, VxVM resets the serial IDs to 0 for the imported disks. The actual and expected serial IDs for any disks in the disk group that are not imported at this time remain unaltered.