[HBASE-7923] force unassign can confirm region online on any RS to get rid of double assignments.

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.95.1
• Hadoop Flags: Reviewed
• Assignee: rajeshbabu
• Reporter: rajeshbabu
• Created: 25/Feb/13 09:23
• Updated: 23/Sep/13 19:08
• Resolved: 03/Apr/13 23:17

Description

Presently in force unassign we are offlining a region from AM and reassigning it, which may cause double assignments.

        this.assignmentManager.regionOffline(hri);
        assignRegion(hri);

Any way if a region is not served by any RS we are offlining the region from AM.

       if (t instanceof NotServingRegionException) {
          if (transitionInZK) {
            deleteClosingOrClosedNode(region);
          }
          regionOffline(region);
          return;
        } 

We can change as below just to confirm whether region online on any RS.

this.assignmentManager.unassign(hri,force);
if(!this.assignmentManager.getRegionStates().isRegionInTransition(hri) && !this.assignmentManager.getRegionStates().isRegionAssigned(hri) ){
	assignRegion(hri);
}