08-16-2017 03:54 PM
My primary master died due to scheduled maintenance and my backup master failed to kick in
CM Agent has tried to start it up but could not initialize the namespace table
After several manual efforts where I followed https://community.cloudera.com/t5/Storage-Random-Access-HDFS/HBase-Master-Failed-to-become-active-ma...
I did the following only
rmr /hbase/meta-region-server rmr /hbase/rs rmr /hbase/splitWAL rmr /hbase/backup-masters rmr /hbase/table-lock rmr /hbase/flush-table-proc rmr /hbase/region-in-transition rmr /hbase/running rmr /hbase/balancer rmr /hbase/recovering-regions rmr /hbase/draining rmr /hbase/namespace rmr /hbase/hbaseid rmr /hbase/table
I got the a master to come up after setting hbase.master.namespace.init.timeout to some absurd value
I see the master registering dead region servers (though I cannot find where it pick them up, not in the WAL, Archive or data)
and I see the master registering the following
Starting namespace manager (since 1hrs, 20mins, 5sec ago)
even though cloudera manager shows healthy
list the catalog in hbase shell gives me the following error
hbase(main):004:0> list TABLE ERROR: org.apache.hadoop.hbase.PleaseHoldException: Master is initializing at org.apache.hadoop.hbase.master.HMaster.checkInitialized(HMaster.java:2373) at org.apache.hadoop.hbase.master.MasterRpcServices.getTableNames(MasterRpcServices.java:907) at org.apache.hadoop.hbase.protobuf.generated.MasterProtos$MasterService$2.callBlockingMethod(MasterProtos.java:55650) at org.apache.hadoop.hbase.ipc.RpcServer.call(RpcServer.java:2182) at org.apache.hadoop.hbase.ipc.CallRunner.run(CallRunner.java:112) at org.apache.hadoop.hbase.ipc.RpcExecutor$Handler.run(RpcExecutor.java:185) at org.apache.hadoop.hbase.ipc.RpcExecutor$Handler.run(RpcExecutor.java:165)
fsck /hbase -files -blocks shows healthy
hbck shows zero inconsistencies
I am on version
I did have a master colocated with a region server and was wondering if I ran into this
and then this
as the cause of the failed backup kicking in
But I cannot determine why I am getting namespace manager would take so long to initialize
08-17-2017 09:20 AM
left master alone to see if it can resolve
Starting namespace manager (since 11hrs, 55mins, 3sec ago)
unfortunately I cannot find any logs on what exactly its trying to do
03-27-2018 06:19 PM
Wish we could have fixed this for you... The only ideas I had involved some serious low level debugging / tracing while it was stuck in this state. Hope things are better now.
02-08-2019 05:06 AM
Not sure which version of CDH you met with this issue. Note that the hbase namespace table is a system table required for HBase to function properly. This table is not handled with a higher priority than other tables as noted in HBASE-14190. If the HBase Master tries to split a WALs on dead or ghost Region Servers then the HBase Master might get stuck trying to split these WALs on invalid Region Servers. The HBase Master can also get stuck trying to split corrupt 83-byte or smaller WAL files on startup in which case just sidelining those blocking WAL files would help. So increasing the hbase.master.namespace.init.timeout may or may not help depending on whether the Master is stuck with any other tasks like WAL splitting.
Another workaround is to recreate the hbase:namespace table in which case it will get loaded quickly.