ORA Database Error Messages ORA-15013: diskgroup “string” is already mounted September 9, 2015 mpbod ORA-15013: diskgroup "string" is already mounted Cause: An ALTER DISKGROUP MOUNT command specified the name of a diskgroup which is already mounted by the current ASM instance. Action: Check the name of the diskgroup. Back to previous menu Share this:Click to email a link to a friend (Opens in new window)Click to print (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on LinkedIn (Opens in new window)Click to share on Tumblr (Opens in new window)Click to share on Twitter (Opens in new window)Click to share on Pinterest (Opens in new window)Click to share on Reddit (Opens in new window)Click to share on Pocket (Opens in new window)