Question about LUN ID

[dslechten]

Hello,

i'm a little bit confused about the LUN ID, in my knowledge this rule applies for the LUN ID

" A LUN shared by multiple hosts MUST be presented with the SAME LUN ID to all hosts "

But today I added a new LUN to two hosts, and in one host it had LUN ID 7 and on another host it had LUN ID 1, and you could see the on both hosts the content of the LUN.

So my question is now, The LUN ID that must be presented to the host, is that on storage level or on ESX level.

Thank you

[NHATech]

On the storage array you should have the option to specify the LUN ID.

You may need to present the LUN to each host one at a time.

Certainly on our HP EVA8000 you can only specify the LUN ID if you present to a single host (at a time), otherwise it chooses the first (lowest) available ID on each host.

[dslechten]

On the storage array you should have the option to specify the LUN ID.

You may need to present the LUN to each host one at a time.

Certainly on our HP EVA8000 you can only specify the LUN ID if you present to a single host (at a time), otherwise it chooses the first (lowest) available ID on each host.

today we configured a siemens storage, the LUN on the storage had ID number 19, on one esx host number 7 and on another number 1...So this what it made confusing for me

If I see it right here, is that the LUN ID on the storage array can be different from the LUN ID that is shown in the esx..

[BUGCHK]

Unfortunately, the term "LUN ID" is not unambigous and can be used in different places for different things. On some storage arrays, "LUN ID" is indeed used to identify an internal storage ressource (aka. logical / virtual disk, volume, ...). For ESX, it is important to which "SCSI LUN address" the ressource has been mapped.

If different ESX servers can access the same VMFS via different "LUN addresses", somebody must have change the option "LVM.DisallowSnapshotLUN" to 0.