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From Dan Retzlaff <dretzl...@gmail.com>
Subject Re: SSTable symlinks
Date Mon, 13 Feb 2012 20:15:15 GMT
Too easy. Does anybody have a more difficult approach? :) Just kidding.
Thanks, Aaron.

On Mon, Feb 13, 2012 at 11:43 AM, aaron morton <aaron@thelastpickle.com>wrote:

> I am nursing an overloaded 0.6 cluster
>
> Shine on you crazy diamond.
>
> If you have some additional storage available I would:
>
> 1) Allocate a data directory for each node, stop the node and add the
> directory to the config for each node in the DataFileDirectory
>   <DataFileDirectories>
>       <DataFileDirectory>/var/lib/cassandra/data</DataFileDirectory>
>   </DataFileDirectories>
>
> 2) The nodes will now create SSTables in the new directory. Bring it back
> up and compact.
>
> 3) Once you have compacted I would recommend stopping the node, moving the
> SSTables back to the local node and removing the additional data file
> directory.
>
> Hope that helps.
>
>
> -----------------
> Aaron Morton
> Freelance Developer
> @aaronmorton
> http://www.thelastpickle.com
>
> On 14/02/2012, at 7:10 AM, Dan Retzlaff wrote:
>
> Hi all,
>
> I am nursing an overloaded 0.6 cluster through compaction to get its disk
> usage under 50%. Many rows' content have been replaced so that after
> compaction there will be plenty of room, but a couple of nodes are
> currently at 95%.
>
> One strategy I considered is temporarily moving a couple of the larger
> SSTables to an NFS mount and putting symlinks in the data directory.
> However, Jonathan says that Cassandra is not okay with symlinked SSTables
> [1]. Can someone elaborate on why this won't work?
>
> If a hack like this is not possible, then I am at a loss for options other
> than ungracefully dropping the node from the cluster and reconstructing its
> data from other replicas. If anyone has recovered from a similar situation,
> I would appreciate your advice.
>
> Regards,
> Dan
>
> [1]
> http://mail-archives.apache.org/mod_mbox/cassandra-user/201106.mbox/%3CBANLkTina%2BtZf9BhQwzW0Fnv-KAL7%2BKZArQ%40mail.gmail.com%3E<http://mail-archives.apache.org/mod_mbox/cassandra-user/201106.mbox/%3CBANLkTina+tZf9BhQwzW0Fnv-KAL7+KZArQ@mail.gmail.com%3E>
>
>
>
>

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