question fsimage NFS backup with HDFS HA QJM in Archives of Support Questions (Read Only)

fsimage NFS backup with HDFS HA QJM

shanek — Wed, 09 Apr 2014 14:47:28 GMT

Is it still recommended to add a NFS mount to dfs.namenode.name.dir for off node fsimage backups if using HDFS HA with QJM?

Thanks,

-Shane

Re: fsimage NFS backup with HDFS HA QJM

Harsh J — Thu, 10 Apr 2014 00:52:09 GMT

This is not really required in a HA setup, since you already have two
independent fsimage copies being made at 2x NNs.

Re: fsimage NFS backup with HDFS HA QJM

bwparang — Mon, 26 Jun 2017 09:15:15 GMT

Hello, harsh.

I have a question about this subject. ( I know this is pretty old issue ... )

I'm using namenode HA(QJM). And for more redundancy, I set "dfs.namenode.name.dir" to multiple directories and one of them is a nfs mounted on other server( especially on master node ).

But in this post and on the Cloudera's deploying guide site( https://www.cloudera.com/documentation/enterprise/5-4-x/topics/cdh_ig_hdfs_cluster_deploy.html ), they say "If you are using HA, you should not configure these directories on an NFS mount".

Why Cloudera says that?

Is it just "no more required" NFS under HA?

or Is there any potential problem using NFS directory under HA?