This alert is triggered if the number of corrupt or missing blocks exceeds the
configured critical threshold. This alert uses the check_hdfs_blocks
plugin.
Some DataNodes are down and the replicas that are missing blocks are only on those DataNodes
The corrupt/missing blocks are from files with a replication factor of 1. New replicas cannot be created because the only replica of the block is missing
For critical data, use a replication factor of 3
Bring up the failed DataNodes with missing or corrupt blocks.
Identify the files associated with the missing or corrupt blocks by running the Hadoop
fsck
commandDelete the corrupt files and recover them from backup, if it exists