Vgimport and export in service gaurd?

[seenivasan]

Dear Team,

Kindly explain Vgimport and export?How it's acting while excute time?

[Stephen Doud]

If Serviceguard packages use LVM shared storage, then vgexport and vgimport becomes a needed tool to insure all nodes /etc/lvmtab are synced with the current list of device special files owned by each shared volume group.

vgexport is used to remove a volume group and the list of disk special files that are associated with the VG from /etc/lvmtab. This may be necessary if a VG is modified (ie, vgextend, vgreduce) on a different node in the cluster.

vgimport is used to load /etc/lvmtab with the complete list of device special files associated with a particular volume group (including alternate links/paths to the LUNs).

Further detail on how and when to use vgexport and vgimport can be found by searching past threads in this forum.

[seenivasan]

Dear from following o/p kindly explain about vgimport and vgexport?

server1:
# strings /etc/lvmtab
/dev/vglock
/dev/disk/disk12
# vgexport -v -p -s -m vglock.map /dev/vglock
# rcp vglock.map denver:/

server2:
# mkdir /dev/vglock
# mknod /dev/vglock/group c 64 0x010000
# vgimport -v -s -m vglock.map vglock

[James R. Ferguson · Accepted solution]

HI:

> kindly explain about vgimport and vgexport?

Your *first* attempt to understand this should be to *read* the manpages:

http://h20000.www2.hp.com/bc/docs/support/SupportManual/c02273768/c02273768.pdf

http://h20000.www2.hp.com/bc/docs/support/SupportManual/c02273771/c02273771.pdf

Regards!

...JRF...

[Steven E. Protter]

Shalom,

vgimport imports or brings in a volume group setup to a system that has already been saved.

vgexport exports and clears a volume group configuration. It removes configuration of /dev/vg##

You will need to provide some more context as to your goals to get more specific information from me.

SEP

[Benoy Daniel]

# vgexport -v -p -s -m vglock.map /dev/vglock
# rcp vglock.map denver:/

This mean it will do a vgexport in preview mode and create the map file , but it wont actually export the vg. Copy the map file to other node and do a vgimport. This is what it is mentioned below.

server2:
# mkdir /dev/vglock
# mknod /dev/vglock/group c 64 0x010000
# vgimport -v -s -m vglock.map vglock

[seenivasan]

Dear All,
from the above concerns my understanding is while use vgexport command does not delete any vg.But that particular copy of vg information only stored on that particular file name.
In second node using vgimport command it's create the vg as well as lv also.it is correct? or wrong?

In that time we no need to create manual vg and lv using Vgcreate and lvcreate command.
after vgimport command we should activate the particular vg.

if it's wrong please let me konw.

Regards,
Seenivasan P

[Shibin_2]

>> my understanding is while use vgexport command does not delete any vg.

Simple vgexport command deletes VG. But with -p option, it preserve and export the structure.

>> after vgimport command we should activate the particular vg.

No. Because, it is your failover node. Activating VG on this node will be taken care by your package, when failover happens. You shouldn't do manually.