[HBASE-9773] Master aborted when hbck asked the master to assign a region that was already online

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.98.0, 0.96.1
• Hadoop Flags: Reviewed
• Assignee: Jimmy Xiang
• Reporter: Devaraj Das
• Created: 15/Oct/13 20:43
• Updated: 16/Dec/13 18:46
• Resolved: 17/Oct/13 17:29

Description

Came across this situation (with a version of 0.96 very close to RC5 version created on 10/11):

The sequence of events that happened:

1. The hbck tool couldn't communicate with the RegionServer hosting namespace region due to some security exceptions. hbck INCORRECTLY assumed the region was not deployed.
In output.log (client side):

2013-10-12 10:42:57,067|beaver.machine|INFO|ERROR: Region { meta => hbase:namespace,,1381564449706.a0ac0825ba2d0830614e7f808f31787a., hdfs => hdfs://gs-hdp2-secure-1381559462-hbase-12.cs1cloud.internal:8020/apps/hbase/data/data/hbase/namespace/a0ac0825ba2d0830614e7f808f31787a, deployed =>  } not deployed on any region server.
2013-10-12 10:42:57,067|beaver.machine|INFO|Trying to fix unassigned region...

2. This led to the hbck tool trying to tell the master to "assign" the region.
In master log (hbase-hbase-master-gs-hdp2-secure-1381559462-hbase-12.log):

2013-10-12 10:52:35,960 INFO  [RpcServer.handler=4,port=60000] master.HMaster: Client=hbase//172.18.145.105 assign hbase:namespace,,1381564449706.a0ac0825ba2d0830614e7f808f31787a.

3. The master went through the steps - sent a CLOSE to the RegionServer hosting namespace region.
From master log:

2013-10-12 10:52:35,981 DEBUG [RpcServer.handler=4,port=60000] master.AssignmentManager: Sent CLOSE to gs-hdp2-secure-1381559462-hbase-1.cs1cloud.internal,60020,1381564439794 for region hbase:namespace,,1381564449706.a0ac0825ba2d0830614e7f808f31787a.

4. The master then tried to assign the namespace region to a region server, and in the process ABORTED:
From master log:

2013-10-12 10:52:36,025 DEBUG [RpcServer.handler=4,port=60000] master.AssignmentManager: No previous transition plan found (or ignoring an existing plan) for hbase:namespace,,1381564449706.a0ac0825ba2d0830614e7f808f31787a.; generated random plan=hri=hbase:namespace,,1381564449706.a0ac0825ba2d0830614e7f808f31787a., src=, dest=gs-hdp2-secure-1381559462-hbase-9.cs1cloud.internal,60020,1381564439807; 4 (online=4, available=4) available servers, forceNewPlan=true
2013-10-12 10:52:36,026 FATAL [RpcServer.handler=4,port=60000] master.HMaster: Master server abort: loaded coprocessors are: [org.apache.hadoop.hbase.security.access.AccessController]
2013-10-12 10:52:36,027 FATAL [RpcServer.handler=4,port=60000] master.HMaster: Unexpected state : {a0ac0825ba2d0830614e7f808f31787a state=OPEN, ts=1381564451344, server=gs-hdp2-secure-1381559462-hbase-1.cs1cloud.internal,60020,1381564439794} .. Cannot transit it to OFFLINE.
java.lang.IllegalStateException: Unexpected state : {a0ac0825ba2d0830614e7f808f31787a state=OPEN, ts=1381564451344, server=gs-hdp2-secure-1381559462-hbase-1.cs1cloud.internal,60020,1381564439794} .. Cannot transit it to OFFLINE.

AssignmentManager.assign(HRegionInfo region, boolean setOfflineInZK, boolean forceNewPlan)

is the method that does all the above. This was called from the HMaster with true for both the boolean arguments.

Issue Links

• is related to: HBASE-9793 Offline a region before it's closed could cause double assignment