Did you jstack the region server before killing it? We could see what was still living, although logs might also give us a clue. As long as the client ZK thread is alive, the znode will stay up.
About the last message: > org.apache.hadoop.hbase.zookeeper.RegionServerTracker: No HServerInfo found > for H3S3,60020,1308946657608 That's usually given when you have a DNS issue, where the hostname and FQDN are mixed up. See http://hbase.apache.org/book/os.html#dns J-D On Mon, Jun 27, 2011 at 10:45 AM, Matt Davies <[email protected]> wrote: > All, > > You may have seen my previous email regarding Master node crashing, but upon > further research we may have other issues. > > I went out to the RegionServer (H3S3) and verified that the process was > running. There was no meaningful log output, and the last output was from > 48 hours ago indicating a log roll. > > *Previous State:* > Master died (H3M1) > > *Corrective Actions:* > I restarted the master out on H3M1, and it started by trying to recover logs > out on H3S3. There were many entries like > > 2011-06-27 11:36:25,639 WARN org.apache.hadoop.hbase.util.FSUtils: Waited > 1701352ms for lease recovery on > hdfs://H3M1:8020/hbase/.logs/H3S3,60020,1308946657608/H3S3%3A60020.1309015083129:org.apache.hadoop.hdfs.protocol.AlreadyBeingCreatedException: > failed to create file > /hbase/.logs/H3S3,60020,1308946657608/H3S3%3A60020.1309015083129 for > DFSClient_hb_m_H3M1:60000_1309194478697 on client 10.x.x.x, because this > file is already being created by > DFSClient_hb_rs_H3S3,60020,1308946657608_1308946657819 on 10.5.241.203 > at > org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFileInternal(FSNamesystem.java:1196) > at > org.apache.hadoop.hdfs.server.namenode.FSNamesystem.appendFile(FSNamesystem.java:1284) > at org.apache.hadoop.hdfs.server.namenode.NameNode.append(NameNode.java:596) > at sun.reflect.GeneratedMethodAccessor48.invoke(Unknown Source) > at > sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) > at java.lang.reflect.Method.invoke(Method.java:597) > at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:557) > at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1416) > at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1412) > at java.security.AccessController.doPrivileged(Native Method) > at javax.security.auth.Subject.doAs(Subject.java:396) > at > org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1115) > at org.apache.hadoop.ipc.Server$Handler.run(Server.java:1410) > > > Then we decided to kill -9 the regionserver process out on H3S3, and > received the following in the master: > > 2011-06-27 11:36:26,006 INFO > org.apache.hadoop.hbase.zookeeper.RegionServerTracker: RegionServer > ephemeral node deleted, processing expiration [H3S3,60020,1308946657608] > 2011-06-27 11:36:26,006 INFO > org.apache.hadoop.hbase.zookeeper.RegionServerTracker: No HServerInfo found > for H3S3,60020,1308946657608 > > > Ultimately, the master came up and transitioned the regions to a different > regionserver. > > Is there a situation where the regionserver may become unresponsive yet the > zookeeper client portion of the process can still check in and tickle > zookeeper so the master thinks it alive? I think this may be why, in my > previous post, the master tried to assign to H3S3 and died in the attempt. > > > Thanks! > -Matt >
