Add existing LUN to new Host ESX 3.0.1

[scotty_p]

I've got 2 hosts connected to a LUN. All of our vms are stored on this LUN. I have created a 3rd host and want to

attach that LUN to it. When I try, I get the error

Warning: The current disk layout will be destroyed. All filesystems and data will be lost permanently.

What is the best way to attach this LUN without destroying the data?

Thanks,

Scott

[avarcher]

Sounds like you are using 'Add Storage' from the 'storage' window, this is used to create new VMFSs - not what you want. If you click on the 'Storage adapters' link, then select the 'rescan' link in the top right corner this will make your server go to the san and discover the LUN and the VMFS. If the LUN is still not visible after this then you will need to check to ensure the LUN is being presented to your server.

See how you go on and repost.

[christianZ]

Can you post:

"esxcfg-vmhbadevs -q" from one of the old hosts and from the new one

[scotty_p]

That's right. I'm doing it from Add Storage.

I've rescanned the adapters and I can see the LUN. It's just not listed under "Storage".

Don't I need to have it available under Storage in order to add vms to it from this host?

[khughes]

have you added the WWN to your switch/SAN for that new host so the new host can talk to your san?

[scotty_p]

Here is the output from esxcfg-hbadevs -q

New Server:

vmhba4:0:0 /dev/sda

vmhba5:0:0 /dev/cciss/c0d0

Existing Server:

vmhba0:2:0 /dev/sda

vmhba6:0:0 /dev/cciss/c0d0

[christianZ]

Here is the output from esxcfg-hbadevs -q

New Server:

vmhba4:0:0 /dev/sda

Is that san lun ??

vmhba5:0:0 /dev/cciss/c0d0

Existing Server:

vmhba0:2:0 /dev/sda

Is that san lun, but not the same as above?

vmhba6:0:0 /dev/cciss/c0d0

>

[scotty_p]

Yes. The SAN looks good. I can see the LUN from the new host. It just hasn't been added as new storage yet on this host

[Dave_Mishchenko · Accepted solution]

If things are setup correctly, it'll be sufficient to just do a rescan in Storage Adapters and the datastore will then be listed in Storage. You might want to check that the LUN has been assigned to this server with the same LUN ID as the other hosts.

[scotty_p]

I did rescan, but it doesn't appear under storage, unless I try to manually add it, which then tells me all data will be destroyed.

The EMC is not set up for LUN masking or selective presentation. Everything should be able to see the LUN by default.

You might want to check that the LUN has been assigned to this server with the same LUN ID as the other hosts.

Do you mean in Virtual Center or on the EMC?

[scotty_p]

Very bizarre. The LUN finally showed up. I'm not sure why it took so long, but at least it's there.

I'm going to take a look at the SAN.

Thanks for all your help.

[khughes]

Sometimes it takes a couple re-scans for everything to show up properly, we usually have to rescan ~2 times if we want to add LUN storage to a host

[petedr]

We had one customer who I think had in their procedures to rescan twice after adding a LUN to a host for it to show up properly.