We ran into an issue where we needed an entire SAN frame retired. Problem is, there are several datastores and several guests running on that frame.

I wanted to script it out, which worked just fine. Then, we had more to do, so I edited the script and ran it again. After the third or fourth time, I decided to write a script that takes params via the cli.

Make sure your datastore names are similar, for instance, mine appends ‘_New’ to the end. So my datastores have to be named like this: ‘vmdatastore’ and ‘vmdatastore_New’. It will get all guests on the datastore and migrate them one by one over to the new datastore. When done, just delete the old datastore (or rename it to _Old) and rename the new one to match.

My script:

#lets get our cli args
param([string]$vc = "vc", [string[]]$datastores = "datastores")

#add the snapin, just in case
Add-PSSnapin VMware.VimAutomation.Core

#check to make sure we have both args we need
if (($vc -eq "vc") -or ($datastores -eq "datastores"))
	{
	write-host `n "Migrate-Datastores moves all running VMs from one LUN to a new LUN of the same name with `"_New`" on the end" `n
	Write-host `n "Required parameters are vc and datastore" `n `n "Example: `"Migrate-Datastores -vc vcenterserver -datastores `(`"datastore1`",`"datastore2`",`"datastore3`)`"`"" `n
	break
	}

#connect to VC

Connect-VIServer $vc

write-host "Migrating these datastores:" $datastores

foreach ($datastore in $datastores)
{
    Write-host "Moving all Servers residing on" $datastore
    $servers = get-vm -datastore $datastore
    foreach ($server in $servers)
        {
        $datastore_new = $datastore.ToString() + "_New"
        write-host "Moving" $server "from" $datastore "to" $datastore_new
        Move-VM $server -datastore $datastore_new
        }
}

Write-host "Done moving to new LUNs"

Disconnect-VIServer -confirm:$false

Then, to run it, I simply type this (after saving the file as Migrate-Storage.ps1):

Migrate-Storage -vc vcenterserver -datastores (“datastore1″,”datastore2″,”datastore3″)

This will check datastore1, get all VMs, migrate them to datastore1_New, then move on to the next datastore.