Repair HBase table (unassigned region in transition)

Question

I'm a bit stuck repairing a faulty table (on Hbase 0.92.1-cdh4.0.0, Hadoop 2.0.0-cdh4.0.0)

There is a region in transition that doesn't finish:

Region    State
bf2025f4bc154914b5942af4e72ea063 counter_traces,1329773878.35_766a0b4df75e4381a686fbc07db9e333,1339425291230.bf2025f4bc154914b5942af4e72ea063. state=OFFLINE, ts=Tue Jun 12 11:43:53 CEST 2012 (0s ago), server=null

When I run sudo -u hbase hbase hbck -repair, I get this:

Number of empty REGIONINFO_QUALIFIER rows in .META.: 0
ERROR: Region { meta => counter_traces,1329773878.35_766a0b4df75e4381a686fbc07db9e333,1339425291230.bf2025f4bc154914b5942af4e72ea063., hdfs => hdfs://hbase001:8020/hbase/counter_traces/bf2025f4bc154914b5942af4e72ea063, deployed =>  } not deployed on any region server.
Trying to fix unassigned region...
12/06/12 11:44:40 INFO util.HBaseFsckRepair: Region still in transition, waiting for it to become assigned: {NAME => 'counter_traces,1329773878.35_766a0b4df75e4381a686fbc07db9e333,1339425291230.bf2025f4bc154914b5942af4e72ea063.', STARTKEY => '1329773878.35_766a0b4df75e4381a686fbc07db9e333', ENDKEY => '1329793347.58_163865765c0a11e184ab003048f0e77e', ENCODED => bf2025f4bc154914b5942af4e72ea063,}

and it just loops.

If I don't do the -repair, I get this:

Number of empty REGIONINFO_QUALIFIER rows in .META.: 0
ERROR: Region { meta => counter_traces,1329773878.35_766a0b4df75e4381a686fbc07db9e333,1339425291230.bf2025f4bc154914b5942af4e72ea063., hdfs => hdfs://hbase001:8020/hbase/counter_traces/bf2025f4bc154914b5942af4e72ea063, deployed =>  } not deployed on any region server.
ERROR: Region { meta => counter_traces,1329816776.95_95b5561f3c1e496598421359a19ac665,1339425297099.ee1fd808d954c9adc9ed95ec2f29d119., hdfs => hdfs://hbase001:8020/hbase/counter_traces/ee1fd808d954c9adc9ed95ec2f29d119, deployed =>  } not deployed on any region server.
12/06/12 11:45:59 DEBUG util.HBaseFsck: There are 134 region info entries
ERROR: There is a hole in the region chain between 1329773878.35_766a0b4df75e4381a686fbc07db9e333 and 1329793347.58_163865765c0a11e184ab003048f0e77e.  You need to create a new .regioninfo and region dir in hdfs to plug the hole.
ERROR: There is a hole in the region chain between 1329816776.95_95b5561f3c1e496598421359a19ac665 and 1329847231.75_b3c50776778b43e088dd7ed865e11331.  You need to create a new .regioninfo and region dir in hdfs to plug the hole.
ERROR: Found inconsistency in table counter_traces

I've run -repair a couple of times before, and it helped. But this time, not anymore.

Ok, so this states to do a manual intervention to fix this. Could someone point me in the right direction on how to do this? A recipe, webpage, example, anything will help.

Thanks, Mario

Answer 1

Mario,

So one of the reasons why a region gets stuck in transition is because, when it is being moved across regionservers, it is unassigned from the source regionserver but is never assigned to another regionserver. One fix that always works for me is by forcibly ASSIGNing it from the hbase shell by :-

assign regionName