topic Re: Presenting Virtual Disk in HPE EVA Storage

Presenting Virtual Disk

Jacky Wing — Mon, 08 Oct 2007 08:53:00 GMT

I have a continous access replication between two sites. I want to be able to present the destination copy of a DR group. In windows it is giving me an error each time i try to present.
do you have any idea?

How to get the controller World Wide Node Name?

Re: Presenting Virtual Disk

mmax — Mon, 08 Oct 2007 10:10:42 GMT

Hi.
All destination disks in DR have to be presented like read only. It's not recommended to present read only disks to windows OS. It should caused problems like bluescreen in past.
For real CA cluster with MS Win cluster you have to buy CLX extension for MS cluster and this CLX will allow you to create automatic presentation and change of source-destination in cluster environment.
have a nice day

Re: Presenting Virtual Disk

Uwe Zessin — Mon, 08 Oct 2007 13:42:49 GMT

The destination vdisks should not be visible to the servers as the multipath component and/or the volume management can become confused due to duplicate devices.

> World Wide Node Name

Many ways...
The WWNN is shown on the OCP and on the Command View EVA's storage system properties page. In most cases, there are also one or two stickers (with the barcode) left and right from the controllers which show the controller WWNN and the checksum.
You can also see it in SSSU or in the Fibre Channel switch's name server - on Brocade switches this is 'nsShow' ('nsAliasShow' can be helpful, too).
And you can see it in the Full Featured MPIO's MMC plugin.
And maybe I have forgotten some more places ;-)

Re: Presenting Virtual Disk

McCready — Mon, 08 Oct 2007 20:32:09 GMT

We create a copy of the disks in the DR group by
- first suspending the replication
- doing a snapclone into a container of each of the disks in the DR group
- resuming the replication
- then present the disks to the intended system.
If you do the above using an RSM or SSSU script it can complete very quickly.

Of course, doing the above costs us more disk space, but it has a variety of pluses, including allowing us to keep replication going while we test the ability to present the disks to the system at our DR site.

Re: Presenting Virtual Disk

Jacky Wing — Wed, 10 Oct 2007 12:03:23 GMT

McCready,

You mean i should present the Snapclone, right?
Suspend
Create snapclone
Resume
Present Snapclone
?

Re: Presenting Virtual Disk

McCready — Wed, 10 Oct 2007 12:09:31 GMT

Yes - just present the snapclone, and you don't have to worry about changing the replication settings and you can always snaplclone again if you think you messed up the copy of the data.