Recently I ran into an issue with ADDM when the 500GB disks which housed our datastore approached max capacity. I proceeded to add a 500 GB disk to the cluster appliances for expansion. I found that it was not possible to expand the data store to this additional disk. I instead had to backup the datastore, wipe the current 500 GB disk, add a 1TB disk to each, and reapply the backup. The 500 GB disks were left unable to be used for the datastore.
I propose that BMC should add the ability for the datastore to be expanded to a second disk on the ADDM appliances instead of forcing the complete data transfer to the new larger disk on each cluster member.