Using EMS HA Monitors

Chapter 2 43
Monitoring Disk Resources
Rules for Using the EMS Disk Monitor with MC/ServiceGuard
links are not configured in separate PVGs, the disk monitor sees all links to the array
as one physical volume, so if one link fails, pv_summary will register DOWN, and
your package will fail over, even if the other link is still up and data is available.
The following sections describe how to make sure your PV links are in physical
volume groups.
Adding PVGs to Existing Volume Groups
If you have already created volume groups, you can create PVGs and put PV links
into them:
1. Create a file called /etc/lvmpvg with permissions 600. See the lvmpvg man
page and HP-UX System Administration Tasks
2. Create an entry for each volume group and assign a different PVG name to each
PV link. The PVG names can be any arbitrary name of your choosing, but must
be unique on the system For example, an array containing 2 volume groups,
vgdance and vgsing, each containing a single LUN and each with 2 PV links
(see Figure 2-4 on page 51) should have the following /etc/lvmpvg file:
VG /dev/vgdance
PVG busA
/dev/dsk/c1t0d0
/dev/dsk/c1t2d0
PVG busB
/dev/dsk/c2t1d0
/dev/dsk/c2t3d0
VG /dev/vgsing
PVG busA
/dev/dsk/c1t0d1
/dev/dsk/c1t2d1
PVG busB
/dev/dsk/c2t1d1
/dev/dsk/c2t3d1
3. Carefully copy the /etc/lvmpvg to each system connected to the disk array.
NOTE Make sure you edit lvmpvg to contain the correct link names in
/dev/dsk/device for that system.
Creating Volume Groups on Disk Arrays Using PV
Links
If you will be monitoring volume groups that use mass storage on disk arrays, you
should use redundant I/O channels from each node, connecting them to separate
controllers on the array. Then you can define alternate links to the LUNs or logical
disks you have defined on the array. Alternate links (known as PV links) to the same
disk should be assigned to different physical volume groups. In SAM, choose the