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: domain of sylvain@datastax.com designates
 209.85.213.44 as permitted sender)
MIME-Version: 1.0
In-Reply-To: <4DF7D397.808@dude.podzone.net>
References: <4DF7D397.808@dude.podzone.net>
Date: Wed, 15 Jun 2011 11:20:31 +0200
Message-ID: <BANLkTimHyFLSkSQsc5KN=hhbosUC7po7aQ@mail.gmail.com>
Subject: Re: Where is my data?
From: Sylvain Lebresne <sylvain@datastax.com>
To: user@cassandra.apache.org
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable

You can use the thrift call describe_ring(). It will returns a map
that associate to each range of the
ring who is a replica. Once any range has all it's endpoint
unavailable, that range of the data is unavailable.

--
Sylvain

On Tue, Jun 14, 2011 at 11:33 PM, AJ <aj@dude.podzone.net> wrote:
> Is there an official deterministic formula to compute the various subsets=
 of
> a given cluster that comprises a complete set of data (redundant rows ok)=
?
> =A0IOW, if multiple nodes become unavailable one at a time, at what point=
 can
> I say <100% of my data is available?
>
> Obviously, the method would have to take into consideration the ring layo=
ut
> along with the partition type, the # of nodes, replication_factor,
> replication strat, etc..
>
> Thanks!
>