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HDFS Name node high avaliability


Hi ,


I have tested Cloudera 5.11 High avaliability active passive with 2 name nodes and noticed that when name node or standby node machines are down the HDFS is not available.


when stoping name node on node 4 getting the error :

hadoop fs -ls /user/hive/warehouse/dwh.db/

llegalArgumentException: error 400


Do I miss anything ?









How did you set up NN AH? Can you provide the context of the two NN, their names, which one you took down so that make it a more clear on what is going wrong here?

The error itself is complaining that the host cannot be resolved. This could be a config issue with the NN HA setup as there should be a service name that resolves, through the config files, to both host. So when NN1 goes offline it will try the NN2. This could be a host name resolution error as well. If DNS or hosts files are not set up correctly then it is simply not able to resolve NN2 from the client.


Hi ,

Thanks for the quick reply .


I used the following instructions :


The service name is nameservice1 (the default) combined from node 4 (active) and node 3(standby)


as I mentioned when shutting down node 4 it seems that the name service is still looking for node 4 .

otherwise it not clear why I'm getting this error .


If it was possible I would add screen shots to the post .


node 3 & 4 roles are :


failover controler

journal node

name node


node manager

hive gateway



The cloudera version is 5.11







If it is still looking for node4 after it goes down then the standby is not in a valid state, could be a quorum issue between the journal nodes, or a state/fencing problem with ZK. Review the logs for these services during the test to try to glean more information.


Thanks 🙂


Checked the logs got the message : Call From to failed on connection exception: Connection refused; For more details see: ""


it seems that for some reason it could not connect to the second name node port 8022 .


Checked if port is listening and got :


root@gc-test-impala28-03:~# netstat -tulpan | grep 8022
tcp        0      1        SYN_SENT    16026/java


Any Idea ?