I’m in the process of reinforcing my vDS knowledge after struggling quite considerably when studying for my VCP and I needed to simplify my lab configuration. I’m currently using the software iSCSI initiators provided for free from Microsoft and after some reading of various articles I decided to go with NFS storage by way of Openfiler. The process is straightforward enough and I’ve outlined the steps I took below. Please bear in mind that this is my lab environment and I had no existing VMs residing on my datastores as it was a fresh build. If you’re going to do this and you do have existing VMs then you’re going to want to install and configure Openfiler and add your NFS datastores to vCenter BEFORE you unmount your exisiting iSCSI datastores.
1. Download Openfiler. There’s a VMware appliance ready for you to download but I grabbed the ISO as I like to run through the installation for myself.
2. Install and configure Openfiler using this awesome guide by @jreypo: http://jreypo.wordpress.com/2010/11/30/configure-nfs-shares-in-openfiler-for-your-vsphere-homelab/ – you’re going to want to create two datastores to satisfy HA heartbeat requirements so follow the guide through twice and add both datastores to each of your hosts.
It should look like this:
4. vMotion your VMs onto the new datastores using cold migration (power off and vMotion).
5. Disable HA on your cluster.
6. Unmount both of your existing iSCSI datastores from your hosts.
7. Delete the unmounted datastores.
8. Enable HA and if necessary reconfigure your hosts for HA again if they throw up warnings.
9. Once that’s done you’re probably going to want to remove the iSCSI software initiator from vCenter and to do that there’s a guide right here: http://jackstromberg.com/2013/01/how-do-i-remove-an-iscsi-software-adapter-in-vmware/– this will involve you rebooting your hosts.
And I’m happy to say that after reconfiguring my storage I was able to migrate my standard switch to a distributed switch with zero hassles.