Managing HP Serviceguard for Linux Ninth Edition, April 2009

2. On ftsys10, activate the volume group, mount the file system, write a date stamp
on to the shared file, and then look at the content of the file:
vgchange --addtag $(uname -n) vgpkgB
vgchange -a y vgpkgB
mount /dev/vgpkgB/lvol1 /extra
echo ‘Written by’ ‘hostname‘ ‘on’ ‘date‘ >> /extra/datestamp
cat /extra/datestamp
You should see something like the following, including the date stamp written by
the other node:
Written by ftsys9.mydomain on Mon Jan 22 14:23:44 PST 2006
Written by ftsys10.mydomain on Mon Jan 22 14:25:27 PST 2006
Now unmount the volume group again, and remove the tag you added in step 1:
umount /extra
vgchange -a n vgpkgB
vgchange --deltag $(uname -n) vgpkgB
NOTE: The volume activation protection feature of Serviceguard for Linux
requires that you add the tag as shown at the beginning of the above steps when
you manually activate a volume group. Similarly, you must remove the tag when
you deactivate a volume group that will be used in a package (as shown at the
end of each step). As of Serviceguard for Linux A.11.16.07, a tag matching the
uname -n value of the owning node is automatically added to each volume group
defined for a package when the package runs; the tag is deleted when the package
is halted. The command vgs -o +tags vgname will display any tags that are
set for a volume group.
Storing Volume Group Configuration Data
When you create volume groups, LVM creates a backup copy of the volume group
configuration on the configuration node. In addition, you should create a backup of
configuration data on all other nodes where the volume group might be activated by
using the vgcfgbackup command:
vgcfgbackup vgpkgA vgpkgB
If a disk in a volume group must be replaced, you can restore the old disk’s metadata
on the new disk by using the vgcfgrestore command. See “Replacing Disks” in the
“Troubleshooting” chapter.
Preparing Your Systems 169