Anyone using Snap Copy with an EVA?

[John Payne_2]

We have a Compaq(HP) storageworks EVA. Part of the functionality that our Mass Storage guy is telling the users about is a 'snap copy' where he can create a copy of a lun on the san, and present it to a different box or the same box.

Here is the problem. I am not convinced it will work on HPUX. I know we could vgexport the vg associated with the lun, copy it, vgimport the lun, and then copy somewhere else. The mass storage guy is telling users that the copy is transparent and instantaneous, however. He is also telling them that they could have their production data on one lun, and he could copy and present to the same machine to have it mounted twice. (1 for prod., 1 for dev.) I am not convinced at all, because the LVM structures would be the same.

Is there anyone using this on HPUX? If so, how is it working? Please convince me.

Thanks

John

[Stanislav Markovic · Accepted solution]

Hi John,

It is indeed possible to do this -- we have done it at our site.

It is done using vgchgid. The man page has one simple example. You are talking about "a lun", which implies that your situation is simple as well.

In more complicated examples I've found it much easier to use a second host and vgexport/vgimport. If you use vgchgid on a large VG with 100 - 200 LUNs, you have to get the vgchgid command exactly right the first time. One mistake, and you have to repeat the entire process all over again.

HTH,
-- Stanislav

[John Payne_2]

Hey, thanks. That looks pretty straightforward. I'll try it later today.

John

[John Payne_2]

Thanks.

That works great!

John