Storage Foundation 8.0.2 Administrator's Guide - AIX

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.

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 sdp 1215378871.300.vm2850lx13 /dev/vx/rdmp/sdp5
newdg2 sdq 1215378871.300.vm2850lx13 /dev/vx/rdmp/sdp5

              Pool 1
DEVICE DISK DISK ID DISK PRIVATE PATH
newdg3 sdo 1215378871.294.vm2850lx13 /dev/vx/rdmp/sdo5

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 hdisk6

DANAME(DMNAME) || Actual SSB      || Expected SSB
hdisk5( hdisk5 ) || 0.1           || 0.0 ssb ids don't match
hdisk6( hdisk6 ) || 0.1           || 0.1 ssb ids match
hdisk7( hdisk7 ) || 0.1           || 0.1 ssb ids match
hdisk8( hdisk8 ) || 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/hdisk6

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.