Using High Availability Monitors (June 2007)

Monitoring Disk Resources
Rules for Using the HA Disk Monitor with ServiceGuard
Chapter 244
no data available for the 2-way mirrored logical volume, but one copy
still available for the 3-way mirrored volume. The pv_summary would
be wrong for one of those mirrored disk configurations.
• Volume groups representing the same hardware for failover must be
created with exactly the same name on all nodes.
For example, a bus connecting 3 nodes to a disk array must be
defined as part of vg01 on all 3 nodes. It is also recommended that
you use the same names for PVGs containing the same actual disks.
Mirrors that have been split off are treated the same by the HA Disk
Monitor as they are by LVM. When you split off a mirror, you will see a
change in the following resources:
•/vg/vgName/lv/copies/lvName will be reduced by one when the mirror
is split off. If you have created a monitoring request for that resource
that alerts you when the number of copies is changed or is reduced,
you will see an event.
•/vg/vgName/lv/status will have a new /lvName resource instance that
represents the split-off mirror.
•/vg/vgName/lv_summary will change depending on the state of the
new logical volume created by the split mirror.
If you restore the split mirror normally using supported LVM commands,
the HA Disk Monitor will detect the merged mirror and report it.