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Date: Sat, 6 Mar 2010 20:01:19 +0000
Message-ID: <8bc75ecf1003061201rf8c9e5m36e9e684f798f677@mail.gmail.com>
Subject: Re: Managing multi-site clusters with Zookeeper
From: Martin Waite <waite.134@googlemail.com>
To: zookeeper-user@hadoop.apache.org
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I take your point about reliability, but I have no option other than finding
a multi-site solution.

Unfortunately, in my experience sites are much less reliable than individual
machines, and so in a way coping with site failure is more important than
individual machine failure.  I imagine that the risk profile changes
according to the number of machines you have, however.

Thanks for the input
Martin

On 6 March 2010 18:29, Ted Dunning <ted.dunning@gmail.com> wrote:

> What you describe is relatively reasonable, even though Zookeeper is not
> normally distributed across multiple data centers with all members getting
> full votes.  If you account for the limited throughput that this will
> impose
> on your applications that use ZK, then I think that this can work well.
> Probably, you would have local ZK clusters for higher transaction rate
> applications.
>
> You should also consider very carefully whether having multiple data
> centers
> increases or decreases your overall reliability.  Unless you design very
> carefully, this will normally substantially degrade reliability.  Making
> sure that it increases reliability is a really big task that involves a lot
> of surprising (it was to me) considerations and considerable hardware and
> time investments.
>
> Good luck!
>
> On Sat, Mar 6, 2010 at 1:50 AM, Martin Waite <waite.134@googlemail.com
> >wrote:
>
> > Is this a viable approach, or am I taking Zookeeper out of its
> application
> > domain and just asking for trouble ?
> >
>
>
>
> --
> Ted Dunning, CTO
> DeepDyve
>

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