topic Replication to 2-nd EVA and presenting to the same host in HPE EVA Storage

Replication to 2-nd EVA and presenting to the same host

zezo — Wed, 03 Feb 2010 09:47:07 GMT

Hi,
I've such problem: I need to replicate lun1 from eva1 to lun2, eva2. Next I will break the connection between the evas. So here is the problem - how to present lun2 to the same host, so that it "sees" the lun2 as the lun1.
Assume that I will unpresent the lun1. The host is windows.
Thank you.

Re: Replication to 2-nd EVA and presenting to the same host

zezo — Wed, 03 Feb 2010 09:51:24 GMT

Just to add, that when I am doing all of the above, the Windows "wants" to initialize the disk (lun2). It cannot "see" it as (instead of) lun1.

Re: Replication to 2-nd EVA and presenting to the same host

Víctor Cespón — Wed, 03 Feb 2010 09:59:42 GMT

Not the correct way of doing it... When you create a DR group, the destination vdisk can be presented to a host, but the host will not see it or will see it as read-only (that's your choice when creating the DR group). Then you can either:

1) Controlled failover: Destination disk becomes source and is accesible. Source disk becomes destination and read-only or inaccessible.

2) Delete DR group, leaving destination vdisk. You'll have two independent copies of the vdisk, at the moment the DR group was deleted. Then you can unpresent one and present the other.

Obviously the server needs SAN access to both EVAs, so you cannot break the inter-site link.

Re: Replication to 2-nd EVA and presenting to the same host

zezo — Wed, 03 Feb 2010 10:05:56 GMT

I am using "2)", but I am using only one host, zoned to the both evas. And the idea is to replace (transperent to the host) LUN1 (from eva1) with LUN2 (from eva2).
Or if it is easy to understand, I wish to migrate (transperent to the hosts) one eva to another.

Re: Replication to 2-nd EVA and presenting to the same host

Greybeard — Wed, 03 Feb 2010 10:27:09 GMT

in that case present lun1 eva1 and lun2 eva2 to the host at the same time, mount both volumes and then use the o/s to copy data from lun1 to lun2, then remove lun1. job done.

Re: Replication to 2-nd EVA and presenting to the same host

Armin Kerl — Wed, 03 Feb 2010 10:28:29 GMT

You can do it as vcespon says in 2):
- Replicate LUN with Sync Mode to EVA2
- Add Host to EVA2 and Present the LUN
(As vcespon says the Host will not see the LUN)
- Wait until the LUN is Full replicated and in Sync
- ShutDown Host
- Unpresent LUN at EVA1
- Delete DR Droup and choose not to delete the LUN on EVA2
- Present LUN at EVA2
- Start Host