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From Dave Wright <wrig...@gmail.com>
Subject Re: Dynamic adding/removing ZK servers on client
Date Mon, 03 May 2010 18:29:19 GMT
>> Well, that just handles distribution of the list (which isn't really
>> our problem), it doesn't help with restarting the ZK client when the
>> list changes - it only pulls the list once, so you still have to
>> completely shutdown and restart the ZK client.
>>
>
> Well the old server is being shutdown right? If the client were connected to
> that server this would force the client to reconnect to another server, what
> I was suggesting is that the client would ping the "server lookup" service
> as part of this. (so lookup on every disconnect say)

Perhaps we should clarify what you mean by "client" (..would ping..).
If you mean the ZK client library, then that would make sense - rather
than use a static list of servers, each time it was disconnected it
would refresh it's list and pick one.
I took it to mean the client application (using the ZK library). The
issue is that the client application has no way to tell the ZK client
lib to use a different list of servers, other than a complete teardown
of the ZK object & session, which I'm trying to avoid.

>
> Hasn't come up before, but yes I agree it's a useful feature.

Ok, thanks. We don't have a specific ETA to implement it, I just
wanted to explore the option a bit before we finalized some aspects of
our design. Should we do the work I'll submit matches for the Java and
C client.

-Dave

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