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From: Jonathan Ellis <jbellis@gmail.com>
Date: Wed, 14 Jul 2010 20:43:50 -0500
Message-ID: <AANLkTinBnxWOVmtPs7AfVI8Hat1zJgFLZIe_5JYGIpCt@mail.gmail.com>
Subject: Re: node down window
To: user@cassandra.apache.org
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Coordination in a distributed system is difficult.  I don't think we
can fix HH's existing edge cases, without introducing other more
complicated edge cases.

So weekly-or-so repair will remain a common maintenance task for the
forseeable future.

On Wed, Jul 14, 2010 at 4:17 PM, B. Todd Burruss <bburruss@real.com> wrote:
> thx, but disappointing :)
>
> is this just something we have to live with and periodically "repair"
> the nodes? =A0or is there future work to tighten up the window?
>
> thx
>
>
> On Wed, 2010-07-14 at 12:13 -0700, Jonathan Ellis wrote:
>> On Wed, Jul 14, 2010 at 1:43 PM, B. Todd Burruss <bburruss@real.com> wro=
te:
>> > there is a window of time from when a node goes down and when the rest
>> > of the cluster actually realizes that it is down.
>> >
>> > what happens to writes during this time frame? =A0does hinted handoff
>> > record these writes and then "handoff" when the down node returns? =A0=
or
>> > does hinted handoff not kick in until the cluster realizes the node is
>> > down?
>>
>> the latter.
>>
>> > ... is the only way these missed writes are repaired is through read
>> > repair and/or manually kicking off "nodetool repair"?
>>
>> yes.
>>
>
>
>


--=20
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of Riptano, the source for professional Cassandra support
http://riptano.com