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Subject: Re: from zookeper embedded to standalone
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From: Shawn Heisey <apache@elyograg.org>
Message-ID: <56E85345.8070906@elyograg.org>
Date: Tue, 15 Mar 2016 12:24:05 -0600
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On 3/15/2016 10:13 AM, Flavio Junqueira wrote:
> Have you asked on the Solr list? They are probably better equipped to answer your question.
>
> On our end, if you are switching to a new set of servers, it is unclear how you're going to safely migrate your data from the old ensemble to the new one. It is also unclear what will happen with in-flight requests. If it is the same set of servers, then I don't se why you'd have issues. We'd need to know more about your setup, though.

I saw the message on the Solr list, and was going to send Rachid here,
because migrating the zookeeper database successfully to different
servers is something that you can help with better.

Here's the overall steps I'd use:

* Shut down all Solr processes.
* Migrate the zookeeper DB and start the new ensemble.
* Start each Solr server without the -DzkRun option and with a corrected
-DzkHost option.

The middle step is what you fine folks will need to help with.

Drawing from elsewhere on this thread ... what "history" would be lost? 
As far as I know, Solr only cares what's in the database at any given
moment ... but my understanding may be incomplete.

Because Solr includes version 3.4.6, adding/removing servers on the fly
isn't supported, which is why I thought a migration with downtime would
be the best option.

Thanks,
Shawn