Thanks Stack! When I scan the -ROOT- table, it's not empty. So I delete all the records in -ROOT- using as you told:
Hbase > delateall '-ROOT-','.META.,,1' After that, I scan the -ROOT again , the records was indeed deleted. Hbase > scan '-ROOT-' 0 row(s) in 0.0210 seconds. And then, I unassign the META region: Hbase > unassign ".META.,,1" After a long while, I executed list: hbase(main):002:0> list TABLE ERROR: org.apache.hadoop.hbase.client.RetriesExhaustedException: Trying to contact region server null for region , row '', but failed after 7 attempts. Exceptions: org.apache.hadoop.hbase.TableNotFoundException: .META. org.apache.hadoop.hbase.TableNotFoundException: .META. org.apache.hadoop.hbase.TableNotFoundException: .META. org.apache.hadoop.hbase.TableNotFoundException: .META. org.apache.hadoop.hbase.TableNotFoundException: .META. org.apache.hadoop.hbase.TableNotFoundException: .META. org.apache.hadoop.hbase.TableNotFoundException: .META. Here is some help for this command: List all tables in hbase. Optional regular expression parameter could be used to filter the output. Examples: hbase> list hbase> list 'abc.*' In HMaster logs, there's no effect happened: 2011-04-29 11:41:29,609 INFO org.apache.hadoop.hbase.master.LoadBalancer: Skipping load balancing. servers=3 regions=2 average=0.6666667 mostloaded=1 leastloaded=1 2011-04-29 11:46:29,607 DEBUG org.apache.hadoop.hbase.master.CatalogJanitor: Scanned 0 catalog row(s) and gc'd 0 unreferenced parent region(s) 2011-04-29 11:46:29,609 INFO org.apache.hadoop.hbase.master.LoadBalancer: Skipping load balancing. servers=3 regions=2 average=0.6666667 mostloaded=1 leastloaded=1 2011-04-29 11:51:29,609 DEBUG org.apache.hadoop.hbase.master.CatalogJanitor: Scanned 0 catalog row(s) and gc'd 0 unreferenced parent region(s) 2011-04-29 11:51:29,610 INFO org.apache.hadoop.hbase.master.LoadBalancer: Skipping load balancing. servers=3 regions=2 average=0.6666667 mostloaded=1 leastloaded=1 2011-04-29 11:56:29,607 DEBUG org.apache.hadoop.hbase.master.CatalogJanitor: Scanned 0 catalog row(s) and gc'd 0 unreferenced parent region(s) 2011-04-29 11:56:29,609 INFO org.apache.hadoop.hbase.master.LoadBalancer: Skipping load balancing. servers=3 regions=2 average=0.6666667 mostloaded=1 leastloaded=1 2011-04-29 12:01:29,607 DEBUG org.apache.hadoop.hbase.master.CatalogJanitor: Scanned 0 catalog row(s) and gc'd 0 unreferenced parent region(s) 2011-04-29 12:01:29,609 INFO org.apache.hadoop.hbase.master.LoadBalancer: Skipping load balancing. servers=3 regions=2 average=0.6666667 mostloaded=1 leastloaded=1 Any problem exist in my operations? Jieshan Bean -----邮件原件----- 发件人: [email protected] [mailto:[email protected]] 代表 Stack 发送时间: 2011年4月29日 11:41 收件人: [email protected] 抄送: Chenjian 主题: Re: HRegionInfo was null or empty in -ROOT- In general, its usually best to let hbase manage all under the /hbase dir in hdfs. What happens if you scan the -ROOT- table in shell? hbase> scan "-ROOT-" Is it empty there? If so, thats not the real issue. The real issue is why .META. is not being deployed. Try removing the entry in -ROOT- hbase> deleteall ".META.,,1" Then, try doing something like unassigning .META. hbase> unassign .META. Tail the master log. See if the above has any effect. St.Ack 2011/4/28 bijieshan <[email protected]>: > Thanks J-D. > I think it's not this problem. I have checked the logs, there's no DNS > exception. > Some one deleted some hdfs files, use the following method: > > ./hadoop fs -rm > /hbase/.logs/181-6-30-103,60020,1303774895876/181-6-30-103%3A60020.1303774909239 > > I don't know whether these operations can bring any effects. > > You can check the log files from the attachments. > > Jieshan Bean > > -----邮件原件----- > 发件人: [email protected] [mailto:[email protected]] 代表 Jean-Daniel Cryans > 发送时间: 2011年4月29日 10:53 > 收件人: [email protected] > 抄送: Chenjian > 主题: Re: HRegionInfo was null or empty in -ROOT- > > Last time I heard about this issue, it was because of a DNS problem. > Look at your master and region server logs. > > J-D > > On Thu, Apr 28, 2011 at 7:49 PM, bijieshan <[email protected]> wrote: >> Hi, >> >> When I execute command of 'list' in hbase shell, it told me that the >> HRegioninfo was null or empty in -ROOT-. >> Did the -ROOT- table value got corrupted or any other reasons cause this >> problem? >> >> Here's the info from the 'list' and 'hbck' tool: >> -------------------------------------------------------------------------------------------------------------------- >> hbase(main):001:0> list >> TABLE >> 11/04/29 10:46:23 INFO jute.BinaryInputArchive: Expecting maxBufferString as >> an integer but got as null.Hence setting to default value 1048575 >> >> ERROR: org.apache.hadoop.hbase.client.RetriesExhaustedException: Trying to >> contact region server null for region , row '', but failed after 7 attempts. >> Exceptions: >> java.io.IOException: HRegionInfo was null or empty in -ROOT-, >> row=keyvalues={.META.,,1/info:server/1304015789456/Put/vlen=13, >> .META.,,1/info:serverstartcode/1304015789456/Put/vlen=8} >> java.io.IOException: HRegionInfo was null or empty in -ROOT-, >> row=keyvalues={.META.,,1/info:server/1304015789456/Put/vlen=13, >> .META.,,1/info:serverstartcode/1304015789456/Put/vlen=8} >> java.io.IOException: HRegionInfo was null or empty in -ROOT-, >> row=keyvalues={.META.,,1/info:server/1304015789456/Put/vlen=13, >> .META.,,1/info:serverstartcode/1304015789456/Put/vlen=8} >> java.io.IOException: HRegionInfo was null or empty in -ROOT-, >> row=keyvalues={.META.,,1/info:server/1304015789456/Put/vlen=13, >> .META.,,1/info:serverstartcode/1304015789456/Put/vlen=8} >> java.io.IOException: HRegionInfo was null or empty in -ROOT-, >> row=keyvalues={.META.,,1/info:server/1304015789456/Put/vlen=13, >> .META.,,1/info:serverstartcode/1304015789456/Put/vlen=8} >> java.io.IOException: HRegionInfo was null or empty in -ROOT-, >> row=keyvalues={.META.,,1/info:server/1304015789456/Put/vlen=13, >> .META.,,1/info:serverstartcode/1304015789456/Put/vlen=8} >> java.io.IOException: HRegionInfo was null or empty in -ROOT-, >> row=keyvalues={.META.,,1/info:server/1304015789456/Put/vlen=13, >> .META.,,1/info:serverstartcode/1304015789456/Put/vlen=8} >> -------------------------------------------------------------------------------------------------------------------- >> HBase hbck tool: >> -------------------------------------------------------------------------------------------------------------------- >> 11/04/29 10:45:42 DEBUG client.HConnectionManager$HConnectionImplementation: >> locateRegionInMeta parentTable=-ROOT-, metaLocation=address: Linux-1:60020, >> regioninfo: -ROOT-,,0.70236052, attempt=4 of 10 failed; retrying after sleep >> of 2000 because: HRegionInfo was null or empty in -ROOT-, >> row=keyvalues={.META.,,1/info:server/1304015789456/Put/vlen=13, >> .META.,,1/info:serverstartcode/1304015789456/Put/vlen=8} >> 11/04/29 10:45:42 DEBUG client.HConnectionManager$HConnectionImplementation: >> Lookedup root region location, >> connection=org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation@42787d6a; >> hsa=Linux-1:60020 >> 11/04/29 10:45:44 DEBUG client.HConnectionManager$HConnectionImplementation: >> Lookedup root region location, >> connection=org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation@42787d6a; >> hsa=Linux-1:60020 >> 11/04/29 10:45:44 DEBUG client.HConnectionManager$HConnectionImplementation: >> locateRegionInMeta parentTable=-ROOT-, metaLocation=address: Linux-1:60020, >> regioninfo: -ROOT-,,0.70236052, attempt=5 of 10 failed; retrying after sleep >> of 4000 because: HRegionInfo was null or empty in -ROOT-, >> row=keyvalues={.META.,,1/info:server/1304015789456/Put/vlen=13, >> .META.,,1/info:serverstartcode/1304015789456/Put/vlen=8} >> 11/04/29 10:45:44 DEBUG client.HConnectionManager$HConnectionImplementation: >> Lookedup root region location, >> connection=org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation@42787d6a; >> hsa=Linux-1:60020 >> 11/04/29 10:45:48 DEBUG client.HConnectionManager$HConnectionImplementation: >> Lookedup root region location, >> connection=org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation@42787d6a; >> hsa=Linux-1:60020 >> 11/04/29 10:45:48 DEBUG client.HConnectionManager$HConnectionImplementation: >> locateRegionInMeta parentTable=-ROOT-, metaLocation=address: Linux-1:60020, >> regioninfo: -ROOT-,,0.70236052, attempt=6 of 10 failed; retrying after sleep >> of 4000 because: HRegionInfo was null or empty in -ROOT-, >> row=keyvalues={.META.,,1/info:server/1304015789456/Put/vlen=13, >> .META.,,1/info:serverstartcode/1304015789456/Put/vlen=8} >> 11/04/29 10:45:48 DEBUG client.HConnectionManager$HConnectionImplementation: >> Lookedup root region location, >> connection=org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation@42787d6a; >> hsa=Linux-1:60020 >> 11/04/29 10:45:52 DEBUG client.HConnectionManager$HConnectionImplementation: >> Lookedup root region location, >> connection=org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation@42787d6a; >> hsa=Linux-1:60020 >> 11/04/29 10:45:52 DEBUG client.HConnectionManager$HConnectionImplementation: >> locateRegionInMeta parentTable=-ROOT-, metaLocation=address: Linux-1:60020, >> regioninfo: -ROOT-,,0.70236052, attempt=7 of 10 failed; retrying after sleep >> of 8000 because: HRegionInfo was null or empty in -ROOT-, >> row=keyvalues={.META.,,1/info:server/1304015789456/Put/vlen=13, >> .META.,,1/info:serverstartcode/1304015789456/Put/vlen=8} >> 11/04/29 10:45:52 DEBUG client.HConnectionManager$HConnectionImplementation: >> Lookedup root region location, >> connection=org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation@42787d6a; >> hsa=Linux-1:60020 >> 11/04/29 10:46:00 DEBUG client.HConnectionManager$HConnectionImplementation: >> Lookedup root region location, >> connection=org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation@42787d6a; >> hsa=Linux-1:60020 >> 11/04/29 10:46:00 DEBUG client.HConnectionManager$HConnectionImplementation: >> locateRegionInMeta parentTable=-ROOT-, metaLocation=address: Linux-1:60020, >> regioninfo: -ROOT-,,0.70236052, attempt=8 of 10 failed; retrying after sleep >> of 16000 because: HRegionInfo was null or empty in -ROOT-, >> row=keyvalues={.META.,,1/info:server/1304015789456/Put/vlen=13, >> .META.,,1/info:serverstartcode/1304015789456/Put/vlen=8} >> 11/04/29 10:46:00 DEBUG client.HConnectionManager$HConnectionImplementation: >> Lookedup root region location, >> connection=org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation@42787d6a; >> hsa=Linux-1:60020 >> -------------------------------------------------------------------------------------------------------------------- >> >> Thanks, >> >> Regards, >> Jieshan bean >> >> >
