Two ESX Servers access the same LUNS

[Jacksoc1615]

Hello,

I'd really appreciate some input here becauseI think this is really messed up, but I want to make absolutely sure before going to my boss. We recently acquired another company that has a two ESX Servers that are SAN attached. When i look at the Navisphere console (EMC) I am seeing that the LUNS have two hosts attached ESX1 and ESX2. I understand that the storage can be partitioned at the VM level, but shouldn't a LUN be owned by either ESX1 or ESX2, but not by both?

Thanks,

C

[lamw · Accepted solution]

False, a LUN can be seen by any number of ESX Servers, usually they're done this way to be presented as shared storage to utilize advanced features such as VMotion/DRS/HA. This just means that the LUN can be seen by both of these ESX Servers, only the VM itself is being locked by a specific ESX Server.

[digitalex]

All esx servers must have access to the same lun via the fabric and the controllers if you want to utilize HA and vmotion. This is how VM's can vmotion to other esx servers via clustered environment. This is capable due to the face the LUNS are formatted in vmfs3. It allows file locking so the data does not get corrupt. Very cool stuff it is. We currently have 3 esx servers in 1 cluster and they access 5 LUNS together. Virtualization is great!

[khughes]

Like the other two have said, that is the correct way to have it setup in order to use the features provided by VMware. It is a different concept to grasp, but all it takes is letting go to some boundries that you once had with physical hardware. There is a nice documentation page provided by VMware under VI3

Here is a nice intro document to ESX 3.5 which goes over the basics and what not,

Good luck and welcome to the world of VMware

• Kyle

[williambishop]

It's been stated several times, but let me allay your fears. On my emc storage, I have as many as 8 esx hosts attached to the same lun. It's fine, it's actually better than fine.

[Jacksoc1615]

Thanks to everyone for the replies. I just found this exact topic in the updated SAN System Design and Deployment Guide.

BIG THANKS to everyone,