Is there a way to disable the default "Datastore usage on disk" alarm set at the vCenter Server level on a particular datastore? My issue is I have about 60 Datastores but only want the alarm disabled on 3 Datastores the rest I want enabled. From what I can see I would have to disable the default alarm set at the vCenter level and then enable\create an alarm on each datastore? Thanks.
As I understand it, that is correct. I would advise scripting the change. Take a look a PowerCLI.
To disable the default alarm, you'll need to recreate the alarm directly on each datastore where you'd like alerts and disable it on the remaining Datastore (hence PowerCli)
You can have a look at http://blogs.vmware.com/vipowershell/2010/12/managing-vsphere-alarms-with-powercli.html for PowerCli help on this if you chose to go the PowerCli route (to flush alarm notifications etc)
Good luck,