moving volume groups from one autoraid to another

[Christopher McCray_1]

I have 2 N-4000 servers with 12h autoraids on each, both visible by both servers for MC Service Guaurd configuration. Currently, all 4 volume groups for both my databases reside on one 12h. I want to physically move two of the 4 vgs to the other autoraid. What is the fastest, most efficient way of doing this?

[Joseph C. Denman]

I have not had the chance to configure MC Service Guaurd......

But I think, if you can see both raids, pvmove might do the trick.

No promises, but my best guess.

Hope this helps.

...jcd...

[linuxfan]

Hi Christopher,

You have two options, once you configure the LUNs on the 2nd Autoraid,

1. you can add the disks on the 2nd autoraid to the existing VGs and mirror the existing Lvols, and once everything is mirrored, you can reduce the disks from on the first autoraid from the VG.

2. you can add the disks on the 2nd autoraid to the existing VGs and pvmove the existing lvols to the new disk and once the data is moved you can reduce the disks on the first autoraid from the VG.

But this would mean the LUN sizes on the 2nd autoraid are the same as that on the 1st autoraid.

Both the solutions can be implemented in multi-user mode, does not need a downtime, but i would strongly suggest backing up the data before doing this.

Also though i personally never had a problem while using pvmove, there have been cases of data corruption.

-HTH
Ramesh

[Sridhar Bhaskarla]

Since this is on MC/Service Guard we need to take care of the volume group configuration on the other system also. Add the LUNs from new 12h into the volume group, establish mirrors, reduce mirrors from the orignal LUNs and reduce them. This is a very straight forwards procedure. However, we need to update the configuration on the other node also. So, you need to create map files on node1 and then import them on node2 to make sure that the modified volume group comes up properly during the failover situation.

-Sri

[linuxfan]

Hi Chris,

I forgot the MC-SG part of your configuration.
Are the packages already running on these servers?

Do you have the cluster lock disk on a different LUN? or is the cluster lock one of the disks you would reducing from the first autoraid. If so you might have to rebuild the cluster.

Also Sri brought up a good point of importing the VGs on the other node. You can do this at the very end once the data is migrated on one machine.

-Regards
Ramesh

[Christopher McCray_1]

To all,

I'll try to answer all the questions:

I have already have the vg map files on both servers and they are imported.

One db is currently packaged and the other is scheduled to be done tonight, which is also when I plan to move the vgs.

The other autoraid has 4 identical LUNs configured as on the active autoraid.

I believe that the cluster lock disk is on a separate LUN, but I will confirm.

I do have a MC Service Guard rep onsite that has been helping me with this implementation; just that it's been a long time since he's delt with an instance like this.

I have one more question concerning the mirroring option; does oracle have to be down to do the mirroring, or can I do this anytime?

I hope I get this MC Service Guard stuff down when I go to the classes the end of September. Thanks in advance for your help.

Chris

[Bill McNAMARA_1]

I'm sure you're still going to have to vgexport and vgimport (like starting all over again) becuase h/w paths and pvra and vgra info is going to change...

Watch out for the autoraid, because your luns are spread across every disk and that becomes a problem in itself.. having to move across every single disk.

On the autoraid, make sure the f/w revision is the same on the two controllers and that you have issued a proper shutdown. In your case, arraymgr -s shut after setting the lock with arraymgr -l (I believe.)

I'll try to search out a doc for you and post it up..


Later,
Bill

[Christopher McCray_1]

Thanks to all for your inputs. They all seem to be good alternatives to my problem. I won't be able to do this until tonight, so wish me luck.