Do setrep -w on the increase to force the new replica before decreasing
again.
Of course, the little script only works if the replication factor is 3 on
all the files. If it's a variable amount you should use the java API to get
the existing factor and then increase by one and then decrease.
Jeff
On Thu, Oct 20, 2011 at 8:44 AM, John Meagher <john.meag...@gmail.com>wrote:
> After a hardware move with an unfortunate mis-setup rack awareness
> script our hadoop cluster has a large number of mis-replicated blocks.
> After about a week things haven't gotten better on their own.
>
> Is there a good way to trigger the name node to fix the mis-replicated
> blocks?
>
> Here's what I'm using for now, but it is very slow:
> for f in `hadoop fsck / | grep "Replica placement policy is violated"
> | head -n3000 | awk -F: '{print $1}'`; do
> hadoop fs -setrep 4 $f
> hadoop fs -setrep 3 $f
> done
>
> John
>
