VxVM fills the root filesystem

Problem

Hosts with a small / filesystem may experience diskspace problems due to large diskgroup backups. These reside in /etc/vx/cbr/bk/ and are made by the /etc/vx/bin/vxconfigbackup command. E.g.:

# /etc/vx/bin/vxconfigbackup -f

Start backing up diskgroup rootdg to /etc/vx/cbr/bk/rootdg.1405590625.9.serv1 ...

VxVM  NOTICE V-5-2-3100 Backup complete for diskgroup: rootdg
Start backing up diskgroup ora1dg to /etc/vx/cbr/bk/ora1dg.1406536462.35.serv1 ...

VxVM  NOTICE V-5-2-3100 Backup complete for diskgroup: ora1dg
Start backing up diskgroup ora2dg to /etc/vx/cbr/bk/ora2dg.1405599579.23.serv1 ...

VxVM  NOTICE V-5-2-3100 Backup complete for diskgroup: ora2dg
Start backing up diskgroup redoadg to /etc/vx/cbr/bk/redoadg.1405667594.30.serv1 ...

VxVM  NOTICE V-5-2-3100 Backup complete for diskgroup: redoadg
Start backing up diskgroup redobdg to /etc/vx/cbr/bk/redobdg.1405668320.35.serv1 ...

VxVM  NOTICE V-5-2-3100 Backup complete for diskgroup: redobdg
Start backing up diskgroup softdg to /etc/vx/cbr/bk/softdg.1405595556.33.serv1 ...

Solution

Decrease the number of backup generations to keep:

echo "NUM_BK=3" >> /etc/vx/cbr/bk_config

Delete any older generations:

# rm /etc/vx/cbr/bk/*/*.5
# rm /etc/vx/cbr/bk/*/*.4