ORA Database Error Messages ORA-15164: cluster rolling downgrade incomplete September 23, 2015 mpbod ORA-15164: cluster rolling downgrade incomplete Cause: The cluster was still performing rolling downgrade. Action: Ensure that all the instances in the cluster are downgraded before retrying the command. 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)