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MapReduce >> mail # user >> Can I switch the IP/host of NN without losing the filesystem?

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Re: Can I switch the IP/host of NN without losing the filesystem?
Hi Jianhui,

If you only has hadoop and not HBase, maybe there is no problem.
Last time we changed IP addresses but not hostname. Our hadoop version is
hadoop 1.0.2, HBase is 0.92.  At beginning, it's ok. But after about 2
hours, the second name node exited and couldn't start , reported
NullPointException. Then we restarted all nodes, but NN couldn't start and
reported the same error.

So you can just have a test. Before your test, REMEMBER to BACKUP ALL YOUR
DATA, especially the name node data and HBase -META-,-ROOT- table.

Good Luck!
Andy Zhou

2013/1/6 Jianhui Zhang <[EMAIL PROTECTED]>

> Hadoop version: hadoop-
> My NN machine has 2 IP addresses and 2 hostnames assigned to them
> respectively. I have configured "fs.default.name" using one of the
> hostnames and used the cluster for a while.
> Now, I may have to move the "fs.default.name" to the other IP/hostname of
> the same machine. If no other configurations change (such as the
> directories), can I simply change "fs.default.name" to the new hostname,
> restart the NN and expect the same filesystem is intact?
> Thanks,
> James