HPUX Cluster

[vinay_26]

We have 3 Node MC/Service gaurd Cluster. One package is running on each node. I need to add addistional disk space on one of the volume group used in the package.

1. Request you to suggest whether the below mentioned step is correct.

* bring down the package
* activate the VG in one node manually
* remove the VG entries with vgexport command on the other 2 nodes.
* make the neccesary changes on the volume group
* export the VG Information into Mapfile
* import the VG Information on the other 2 nodes from the mapfile.
* start the package.

2. Can we do the changes online ie when the package is running without any downtime of package? if yes pls suggest me on that.

[Devender Khatana]

Hi,

It is quite normal and should not include anything else. But as it includes manually enabling the volume group can not be done online atleast I never tried.

HTH,
Devender

[Shyjith P K]

Hi Vinay,

Steps looks ok.
However, vgextend cannot be performed if the volume group is activated in shared mode.

--Shyjith

[vinay_26]

It is activated in Exclusive mode and is not in shared mode.

I was keen to know if i can go ahead directly extending the volume group when the package is on. than update the Vg information on the other 2 nodes with the map file.

[Mark Nieuwboer]

Hi you can do it online if you have online jfs. of course you must be certain that the package not switch during the changes.

* chmod -d
* make the neccesary change
* export the volume group with the -p option to a map.file
* check if the volume group is extended correctly
* remove the VG entries with vgexport on the other nodes.
* import the vg information on the other nodes.
* i always try to start the package on the other nodes to make certian that the packeges also run on that node.
* at last chmod -e packagename.

grtz. Mark

[Devender Khatana]

Hi,

The command for changing package switch over switch should be cmmodpkg & not chmod.

Regards,
Devender

[vinay_26]

It seems that we can extend the VG online. i have a doubt how can we know whether the VG is activated in cluster & shared mode.

When i see in vgdisplay it says AVAILABLE,EXCLUSIVE.

[Cem Tugrul]

Vinay,

under the path /etc/cmcluster
check the cluster.ascii file

Well,on the other hand Hp always recommeded
me to halt package and maintain your FS

good Luck,

[David Child_1]

Vinay,

If you see available,exclusive then the vg is not in shared mode. You will see either available,server or available,client (depending on which server activated the volume group first) if your volume group was activated in shared mode.

As already stated, you should be able to add the space online (as long as you have OnlineJFS).

David

[Devender Khatana]

Hi,

Yes, just confirmed it can be done online but should be checked by switching over packages manually when done.

Also it activates VG's in exclusive node. i.e. only once node accesses at a time. So you will be doing the config changes on the node where package is currently running & rather you can not do it on other nodes as VG is activated on the one where package is currently running.

HTH,
Devender

[vinay_26]

Hi all. Last question on this thread.

I need to export the volume group information from Node 1 and import it on to the other 2 nodes.

Which command is correct

vgexport -m

or

vgexport -f

the documentation tells to use -m option. was keen to know why we cant use -f option for exporting the vgs and import on ther systems

[Devender Khatana · Accepted solution]

Hi,

It is always done with -m option & not -f because it writes PV paths on the file which may be different on the other host. While doing it with MAP file it writes VGID on the map file and all disks are scanned for that VGID while importing the VG.

Also do not forget to use -p option on node1.

HTH,
Devender

[Cem Tugrul]

i am agree with Devender...

Good Luck,

[Shyjith P K]

Hi Vinay,

Use the "-s" option also.

# vgexport â p â v â s â m /tmp/vgXX.map /dev/vgXX


R

[Shyjith P K]

Command is

# vgexport -p -v -s -m /tmp/vgXX.map /dev/vgXX

Rgds
Shyjith