Migrating from Fiber Channel to NFS

[aldikan]

Hi Guys,

The direction we are following dictates that our existing VI3.5 infrastracture with Fiber channel NetApp storage will stop expanding, new NFS NetApp storage will be implemented

and everything will be migrated to NFS.

The plan is to introduce a few more new ESX 3.5 hosts, confiugred with NFS connections and start migration.

I am aware that for successfull migration every ESX host should see every storage, therefore it seems every ESX host should have fiber channel and NFS connections.

Is there way to avoid this prerequisite?

Can I do "Cold" migration? (Meanning shutting down VMs, removing them from inventory and just copying folders over and adding them to inventory from new NFS LUNs)

What would be other ways to achieve this?

Your input is appreciated and points will be rewarded. :smileycool:

[lamw]

For the VMs to eventually function within a cluster, yes all storage should be visible to all your ESX Hosts. When you're talking about migrating, you're going to have to take some downtime for the VMs unless you want to use something like Storage VMotion, this would provide uptime for your VM but you'll have to have all the NFS LUNs presented to all your hosts. If not, then yes, a cold migration will work, just bring up your NFS LUNs and copy it right over. Since your backend storage is going to be the same, could you not modify the NetApp OnTap software to re-present those LUNs and export them via NFS? I'm not a storage admin, just throwing out an idea. Also since the backend isn't changing, if you have to move the data to new set of LUNs, can you not just snapmirror the current LUNs, probably replicate faster? You'll need to re-register your VMs afterwards if you do cold migrations or backend replication

[AndrewSt]

I just did a migration over the weekend, that is very similar to what you are looking at. We moved VM guests from ESX using iSCSI (looks like FC in most respects) to ESX servers using NFS. If you do not want to use Vmotion for Storage to move the VMs, consider using VM Converter to do a V2V.

Only the destination servers saw the NFS storage, and only the source servers say the iSCSI storage. However, the VC server for the NFS storage did not manage the iSCSI ESX server. So these were 'new' to the VC server. Might make a difference with the V2V, but not sure.

All I had to do, was start the Converter, tell it that it was an ESX server I was importing from. I then connected, saw the VMs that were on the server, and was able to pull them in, and put them on the storage I selected. Use advanced option on the datastore destination selection, and you can split the data volumes if you want.

Over all, pretty simple.

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-Andrew Stueve

[aldikan]

Thank you for helpful replies,

Since we will have same VC managing two datacenters:

One datacenter with ESX hosts with Fiber Storage and another datacenter of ESX hosts with NFS,

We will go with cold migration with copying VMs over or hopefully with LUN mirroring from Fiber Channel storage to NFS storage using the NetApp software.

Thank you!

Alex