Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

Figure 6-2
Example of a serial split brain condition that can be resolved
automatically
Partial disk group
imported on host X
1. Disk A is imported on a separate
host. Disk B is not imported. The
actual and expected serial IDs are
updated only on Disk A.
2. The disk group is re-imported
on the cluster. The configuration
copy on Disk A is used to correct
the configuration copy on Disk B
as the actual value of the updated
ID on Disk A is the greatest.
Imported shared disk group
Disk A
Disk A = 1
Configuration
database
Expected A = 1
Expected B = 0
Disk B not imported
Disk B
Disk B = 0
Expected A = 0
Expected B = 0
Disk A
Disk A = 1
Expected A = 1
Expected B = 0
Disk B
Disk B = 0
Expected A = 1
Expected B = 0
Configuration
database
Configuration
database
Configuration
database
■ If the other disks were also imported on another host, no disk can be considered
to have a definitive copy of the configuration database.
Figure 6-3 shows an example of a true serial split brain condition that cannot
be resolved automatically by VxVM.
Creating and administering disk groups
Handling conflicting configuration copies
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