Managing Serviceguard Eighteenth Edition, September 2010

vgcreate -g bus0 /dev/vgdatabase /dev/dsk/c1t2d0
vgextend -g bus1 /dev/vgdatabase /dev/dsk/c0t2d0
CAUTION: Volume groups used by Serviceguard must have names no longer
than 35 characters (that is, the name that follows /dev/, in this example
vgdatabase, must be at most 35 characters long).
NOTE: If you are using cDSFs, you should be using them exclusively.
The first command creates the volume group and adds a physical volume to it in
a physical volume group called bus0. The second command adds the second drive
to the volume group, locating it in a different physical volume group named bus1.
The use of physical volume groups allows the use of PVG-strict mirroring of disks.
4. Repeat steps 1–3 for additional volume groups.
Creating Logical Volumes
NOTE: You can create logical volumes by means of the cmpreparestg (1m)
command. See “Using Easy Deployment Commands to Configure the Cluster” (page 211)
for more information. If you use cmpreparestg, you can skip this step and proceed
to “Making Physical Volume Group Files Consistent” (page 238).
Use a command such as the following to create a logical volume (the example is for
/dev/vgdatabase).
lvcreate -L 120 -m 1 -s g /dev/vgdatabase
This command creates a 120 MB mirrored volume named lvol1. The name is supplied
by default, since no name is specified in the command. The -s g option means that
mirroring is PVG-strict;, that is, the mirror copy of any given piece of data will be in a
different physical volume group from the original.
NOTE: If you are using disk arrays in RAID 1 or RAID 5 mode, omit the -m 1 and
-s g options.
Setting Logical Volume Timeouts
In the event that a I/O request to a logical volume never succeeds (for example, a vital
set of disks fails), your application or file system may block indefinitely. To prevent
this, you can set a timeout on the logical volume. If the device fails to respond within
the timeout period, LVM will return an I/O error to the caller. Set the timeout value
using the -t option of the lvchange command. This sets the timeout value in seconds
for a logical volume. For example, to set the timeout for /dev/vg01/lvol1 to one
minute, enter the following command:
lvchange -t 60 /dev/vg01/lvol1
234 Building an HA Cluster Configuration