Ulrich Kammer 2012-10-02, 13:47
It is fine to run the "hadoop dfsadmin -finalizeUpgrade" command to
complete the upgrade but since it has been a while that you haven't
done that, I expect it may take quite a while to finish as there'll
now be lots of blocks to process for upgrades. However, there should
be no risk in running that command.
On Tue, Oct 2, 2012 at 7:17 PM, Ulrich Kammer <[EMAIL PROTECTED]> wrote:
> in april we have upgraded our version of Hadoop 0.21.0 to version 1.0.1. We
> stuck to the exact instructions in the upgrade documentation as always.
> After a few months we have discovered on the Namenode that here again
> "upgrade for version -32 has been completed. Upgrade is not finalized." is
> displayed. Our question now is, can we run this command without risk again?
> According to our research, this command deletes the directory on the Data
> Nodes "previous" and the directories on the namenode "previous" and
> "previous.checkpoint". It is very important that we here do not lose data. A
> backup is not possible for reasons of cost. Is there eventually an easy way
> to test it?