[JDEV] Jabber load balancing

[Anders Qvist]

On Fri, 5 May 2000, Tyron Stading wrote:

> Can someone tell me how many users Jabber is able to support?

Nobody really knows. In theory, tens of thousands.

> Is the socket connection persistent?

Yes.

> How does the routing for the name resolution work? (i.e.- if 
> person at jabber.org is at person at server1.jabber.org (because of load 
> balancing), how would that message be able to reach that person)

The current scheme doesn't support that. There has been talk about a
mechanism whereby the server will refuse someone to log in, but will
provide the name of another server to try instead.

> I am trying to develop a clustering of these servers, but I needed to know 
> more about how things worked (and I couldn't find anything on the Web 
> site).  Thanks for your help in advance.

Given that the TCP connection is persistent, making Jabber servers
failover is tricky. Load balancing can be achieved only in that
clients are evenly distributed among a cluster of servers. You also need
to centralise the data storage for user messages/rosters.

Anders "Quest" Qvist
NetGuide Scandinavia

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