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hdfs jmxget vs hdfs fsck


hdfs jmxget vs hdfs fsck

New Contributor


I've run into something awkward for me some time ago and I don't have an explanation.

I have 2 namenodes with several datanodes, but today I've just seen that I have some corrupt blocks.

What is awkward is that:

hdfs jmxget -server namenode02 -port 8006 | grep  CorruptBlocks


and when I've checked with hdfs fsck / , I've got:

 Total size:    734930879995888 B (Total open files size: 537967073 B)
 Total dirs:    1501316
 Total files:   113743394
 Total symlinks:                0 (Files currently being written: 137)
 Total blocks (validated):      109063040 (avg. block size 6738587 B) (Total open file blocks (not validated): 133)
 Minimally replicated blocks:   109063040 (100.00001 %)
 Over-replicated blocks:        0 (0.0 %)
 Under-replicated blocks:       0 (0.0 %)
 Mis-replicated blocks:         0 (0.0 %)
 Default replication factor:    3
 Average block replication:     3.001944
 Corrupt blocks:                0
 Missing replicas:              0 (0.0 %)
 Number of data-nodes:          103
 Number of racks:               1
FSCK ended at Mon Feb 12 10:09:10 CET 2018 in 1608344 milliseconds

So with fsck nothing bad regarding the blocks. How is this check made?

Thx in advance !