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What will happen if HDFS_CANARY_HEALTH check status failed? Will the Name node restart?

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What will happen if HDFS_CANARY_HEALTH check status failed? Will the Name node restart?

New Contributor

I have seen a situation wher some of the jobs suddenly failed with error saying "Cannot create a file. Namenode in safe mode." When I check the cloudera manager, HDFS_CANARY_HEALTH check failed. I also observed that the Active namenode become standaby and standby become active. So, if the HDFS_CANARY_HEALTH test fails then Namenode restarts by itself? Can anyone respond to this.

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Re: What will happen if HDFS_CANARY_HEALTH check status failed? Will the Name node restart?

Master Collaborator
The canary test does not have anything with the failover. This just reports to the Cloudera Manager the health status. The actual failover in HA scenario is initiated by a Failover controller(s) - you have probably two NN, 3 (or 5) JNodes and Failover controllers. When the Active NN goes down, the FC brings the standby NN into a Active mode
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Re: What will happen if HDFS_CANARY_HEALTH check status failed? Will the Name node restart?

Master Collaborator
The canary test does not have anything with the failover. This just reports to the Cloudera Manager the health status. The actual failover in HA scenario is initiated by a Failover controller(s) - you have probably two NN, 3 (or 5) JNodes and Failover controllers. When the Active NN goes down, the FC brings the standby NN into a Active mode