The option to increase datastore size is grayed out in vSphere client, when I expected it to be available.
This is an ESXi 5.1 box that was upgraded from 4.1 several months ago. Dell r610 with both internal RAID 5 storage and external local RAID storage (Dell PERC h800 controlling an MD1220 hard drive array). Running fine as v 5.1 for months. All the data stores are VMSF 5.
datastore_ext is located on the external hard drive array. Last night I successfully added a 600gb drive to the array; the virtual disk increased from 1TG to 1.6TB. VMWare sees the drive as having 1.6 TB, but I don't see a way of expanding the datastore or extent.
The datastore remained intact through the expansion of the virtual disk-- it still functions correctly.