How to find health of journalnode?

[#1]

I am going to add new journalnode to my hadoop cluster. So, for scp i need to select a journalnode with all edits without any lag

How to find which journalnode has all edits without any lag?

[#2]

First, remember you need to have an odd number of journalnode (3, 5, 7, etc).

All the Journal nodes should be sync. Tail the log file across all the JN to be sure you are in the same edit.

tail -f /var/log/hadoop/hdfs/hadoop-hdfs-journalnode*.log

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