Move vMware ESX Storage to a new Storage Array

[Alzhy]

We're getting new storage and ditching the old one. Old one is SAN connected. New one is also SAN connected but different vendor.

Are there non-disruptive methods available to perform this? Since I've heard ESX runs on a version of Linux - are their possibly mirroring tools available so migration is trnasparent?

Thanks!

[Uwe Zessin]

Sigh, no, VMware ESX server does not "run _on_ a version of Linux". What you recognize as "a version of Linux" is the "Service Console", also called the "Console Operating System", which is a special virtual machine running a hardend version of Red Hat Linux.

The main hardware is driven by the VMkernel which is VMware proprietary technology, but I digress...

Virtual machines are stored in a VMware ESX server-specific file system called VMFS. The I/O goes completely through the VMkernel which as of today does not have any disk mirroring capability.

If you have a Virtual Center management server and concurrent access to both storage arrays, you can shutdown a VM and then do a "cold migration with datastore relocation" - otherwise you have to unregister the VM, copy the files manually and re-register the VM (no big deal either).

[Alzhy]

Thanks Uwe.

I was actually on the "root" prompt and it's a full Linux OS I see. Even the perf monitoring tools I am accustomed to are available.

On a normal Linux with vMware Server (the freebie)... I've my Virtual Machines (vmdks) sitting on LVM/VxVM managed "volumes" and am able to migrate storage from one disk/array to another. I guess VMFS sits on top of the physical LUN ?

RIght now I guess we've no choice but to use SAN based HW tools to accomplish this.

[Adam Baum]

Nelson,

What you see is not real. As the previous poster said, it's a modified version of Red Hat. VM is very adamant that you do NOT treat it like Linux. Bad things can happen.

Anyway..if you are not in a hurry to migrate, the next version of VMware will support Storage Vmotion. It will take care of migrating a running guest to a different array without having to take down the guest. Your only other choice is to use a SAN replication tool, but you better make sure that it is supported for you source and destination arrays AS WELL AS vmware.

adam

[Uwe Zessin]

> I guess VMFS sits on top of the physical LUN ?

Yes. A VMFS lives inside an MBR-style partition table, like an NTFS or an EXT2 without the use of LVM.

You can log in to the Service Console and type "fdisk -l". Every partition with Id=fb is supposed to store a VMFS.