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From Robert Coli <>
Subject Re: Cassandra snapshot
Date Mon, 02 Jun 2014 19:50:13 GMT
On Mon, Jun 2, 2014 at 12:18 PM, ng <> wrote:

> I need to make sure that all the data in sstable before taking the
> snapshot.
> I am thinking of
> nodetool cleanup

Cleanup does nothing but waste i/o if you have not recently added, removed,
or replaced nodes.

> nodetool repair

Repair cannot actually close the consistency window while writes are
incoming, it can only shorten it.

> nodetool flush
nodetool snapshot
> Am I missing anything else?

Your requirement seems a bit confused. If your goal is to close the
consistency window, it's impossible without turning off writes or writing
everything at CL.ALL. If your goal is not to do that, the above "flush" is
unnecessary. Also, if I recall correctly, "snapshot" flushes as part of the
snapshot process, so it's redundant.

Most people rely on replication + backups to make the consistency window
short enough that they don't care too much about "making sure all the data
in sstable before taking snapshot."


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