Mailing-List: contact user-help@cassandra.apache.org; run by ezmlm
Precedence: bulk
Reply-To: user@cassandra.apache.org
Received-SPF: pass (nike.apache.org: local policy)
DomainKey-Signature: a=rsa-sha1; c=nofws; d=thelastpickle.com; h=content-type
	:mime-version:subject:from:in-reply-to:date
	:content-transfer-encoding:message-id:references:to; q=dns; s=
	thelastpickle.com; b=icbtjOrydbLp+fOLsrgdsnATCrVS+Zwb6yOmAxCkDa3
	A5NnyOO5PoXVS2ATYMHJhzb2HlpEldxecnLoGp3QB/boo3NpLKiMVGPvcxu7T878
	C1FYjtwV7JRAu8Ppx4KEMHUvoL9Luo+tMGZoUpwWOfF50b14lbwsi6c3KVuIvv4k
	=
Content-Type: text/plain; charset=iso-8859-1
Mime-Version: 1.0 (Apple Message framework v1244.3)
Subject: Re: Moving to a new cluster
From: aaron morton <aaron@thelastpickle.com>
In-Reply-To: 
 <CAKkz8Q3XjDvp2sjjBdXskpOXms43hhT_wZQXgS4WuVCYi=Hpcw@mail.gmail.com>
Date: Sun, 25 Sep 2011 16:24:58 +1300
Content-Transfer-Encoding: quoted-printable
Message-Id: <714EADFF-52A6-4EF3-BF32-31F451D91E36@thelastpickle.com>
References: 
 <CAHwsXYm4y6fQ2ANmjana_dRHhT=akaW=Mo2M7-jN2XAnQ3vy_g@mail.gmail.com>
 <901040CC-C1B5-419D-9780-A2D0A00A0DBC@thelastpickle.com>
 <4E7AF745.1080006@borgstrom.se>
 <CAKkz8Q3XjDvp2sjjBdXskpOXms43hhT_wZQXgS4WuVCYi=Hpcw@mail.gmail.com>
To: user@cassandra.apache.org

Thanks sylvain, will look into the new stuff.=20


-----------------
Aaron Morton
Freelance Cassandra Developer
@aaronmorton
http://www.thelastpickle.com

On 22/09/2011, at 9:09 PM, Sylvain Lebresne wrote:

> 2011/9/22 Jonas Borgstr=F6m <jonas@borgstrom.se>:
>> On 09/22/2011 01:25 AM, aaron morton wrote:
>> *snip*
>>> When you start a repair it will repair will the other nodes it
>>> replicates data with. So you only need to run it every RF nodes. =
Start
>>> it one one, watch the logs to see who it talks to and then start it =
on
>>> the first node it does not talk to. And so on.
>=20
> This is not totally true because of
> https://issues.apache.org/jira/browse/CASSANDRA-2610.
> Basically, doing this won't make sure the full cluster is in sync
> (there is a fair
> chance it will, but it's not guaranteed).
> It will be true in 1.0 (though in 1.0 it will be simpler and more
> efficient to just run
> 'nodetool repair --partitioner-range' on every node).
>=20
>=20
>> Is this new in 0.8 or has it always been this way?
>>=20
>> From
>> =
http://wiki.apache.org/cassandra/Operations#Frequency_of_nodetool_repair
>>=20
>> """
>> Unless your application performs no deletes, it is vital that =
production
>> clusters run nodetool repair periodically on all nodes in the =
cluster.
>> """
>>=20
>> So for a 3 node cluster using RF=3D3, is it sufficient to run =
"nodetool
>> repair" on one node?
>=20
> Technically, in the 3 nodes RF=3D3 case, you would need to do repair =
on
> 2 nodes to make sure the cluster has been fully repaired. But it =
becomes
> fairly complicated to know which nodes exactly once you get more than
> 3 nodes in the cluster or you have RF > 3, so to be safe I would =
advise
> sticking to the wiki instruction (until 1.0 at least).
>=20
>>=20
>> / Jonas
>>=20