Using EMS HA Monitors

Chapter 2 37
Monitoring Disk Resources
Disk Monitor Reference
Logical Volume Summary
The logical volume summary tells you how accessible the data is in all logical
volumes in an active volume group. Sometimes the physical connection may be
working, but the application cannot read or write data on the disk. The disk monitor
determines I/O activity by querying LVM, and marks a logical volume as DOWN if
a portion of its data is unavailable.
NOTE The disk monitor cannot determine data accessibility to logical volumes in an
inactive volume group.
The values in Table 2-3 are used by the disk monitor to determine how conditions
compare in logical operations. For example, you may create a request that alerts you
when the condition is greater than or equal to INACTIVE_DOWN.
Table 2-3 Interpreting Logical Volume Summary
Resource Name /vg/vgName/lv_summary
Condition Value Interpretation
UP 1 All logical volumes are accessible, all data is accessible.
INACTIVE 2 The volume group is inactive. This could be because:
• The volume group is active in exclusive mode on another node
in an MC/ServiceGuard cluster. (This is not valid for clusters
running MC/LockManager, because it can support a volume
group being active on more than one node.) Note that
MC/ServiceGuard does allow a volume group to be active in
read-only mode, if it is already active on another node.
• The volume group was made inactive using vgchange -a n
for maintenance or other reasons.
• There was not a quorum of active physical volumes at system
boot, i.e. not enough disks in the volume group were working.
INACTIVE_DOWN 3 The last time the inactive volume was activated, it was DOWN; at
least one logical volume in the volume was inaccessible
DOWN 4 At least one logical volume in the volume group reports a status of
either INACTIVE or DOWN. Note that an inactive logical volume
in an active volume group is rare, but possible. See “Logical
Volume Status” on page 38.