Operation category read is not supported in state standby

The root cause

 Operation category READ is not supported in state standby

spark task checkpoint Of hdfs Path namenode It's dead ,hadoop namenode An error will be reported after switching .

Other knowledge gained in the process

spark from hadoop Get from configuration nn1,nn2 Two namenode He will try one by one Until we find something available , in other words If the first attempt happens to be standby node , Then the message will be displayed , But it will not affect him to continue to try to be normal namenode node .

however If you write dead ip stay checkpoint There will be problems in .