LVM problem in MC/SG env

[Satish Y]

Hi Experts,

We have 4 HP-UX 10.20 K-class servers in an MC/SG cluster. On which one sybase server is running as a package. I saw a strange error today:

-------------------------------------------
Jun 22 05:50:57 - "sys1": Activating volume group vg01 with exclusive option.

Cannot lock "/etc/lvmconf//lvm_lock" still trying ...Activated volume group in E
xclusive Mode.
Volume group "vg01" has been successfully changed.
-------------------------------------------

Above error displayed in package log when Sybase server(package) trying to come up on alternate node and was bouncing.

Can anybody tell me what that error represents?.
Is it anyway related to why package not coming up properly?.
What is /etc/lvmconf/lvm_lock file?.

Thanks in advance.

Cheers...
Satish.

[Satish Y]

Forgot to update, Volume group "vg01" is on the shared disks.

Cheers...
Satish.

[John Palmer]

Hi,

This is not an error. The lvm_lock file is used by LVM commands to ensure that only one update can occur at once, thus preventing possible corruption.

When your package start script attempted to activate vg01, another LVM command was already running. When this finished, vgchange acquired the lock and completed successfully.

Regards,
John

[Amruth]

Hi,

I also agree with Palmer..

Regards,
AR

[Tim D Fulford]

Check /etc/lvmrc, /etc/cmcluster//.sh

The lvmrc starts VG's at start up. make sure it does not start all VG's by default and that vg01 is not among the ones it does.

the .sh may be doing something funny in the section customer_start_commands... Make sure it does not do any vgchanges in this part of the scrit.

Otherwise I agree with above.

Tim

[Steve Post]

Check /sbin/init.d/extramount on your primary node. Maybe you have been activating the volume group here instead via your package.run command file. Just a thought.
steve ^_^

[Sanjay_6]

Hi Satish,

The error message is seen when trying to activate a vg or run a vg command while another configuration related vg command is being run. For eg, say there was a disk problem or a problem with the mirror and a vgsync (rebuild mirror) is in progress. At the same time if a vgchange command is executed for this vg. you'll find the error

"/etc/lvmconf/lvm_lock" still trying.

Hope this helps.

Regds

[Sridhar Bhaskarla]

Satish,

LVM configuration change commands like lvremove, lvcreate, vgchange, vgsync etc keep a lock file until the completion of their execution to ensure the integrity by not allowing another command to run. Sometimes, hardware failures may cause these commands to execute for a long time. If you get this error try to see if there are any commands running by grepping for lv or vg.

-Sri