XMPP, Connect Server, and SRV

[Bron Gondwana]

On Thu, Aug 07, 2008 at 06:24:16PM -0400, Evan Schoenberg wrote:
> Is there a reason we don't use SRV when a connect server is specified  
> for XMPP?  It seems that we should do an SRV lookup on the connect  
> server (as we do for the domain, if no connect server is specified)  
> and then fallback on the specified server/port.
> 
> This would allow connecting to XMPP server foo with username at yourdomain.com 
>   by setting your connect server to foo without having to know foo's  
> actual server details (specific XMPP server address and port).
> 
> Unless there are objections, I'd like to make this change.

Yes please.  Though I'll just throw this in.  My dodgy dnsmasq based
OpenWRT gateway doesn't appear to be handling SRV requests properly,
or maybe something further upstream is losing them.  I'm happy to do
some more research to find out specifically what is going on there 
(when I'm not travelling on a train with no connectivity!)

The symptom was that "dig srv _jabber._tcp.fastmail.fm" returned no
records when run on my laptop at home, and returned the correct value
"5 0 5222 chat.messagingengine.com" when run from our production
servers.

My idea of the correct behaviour is:

a) if an explicit server name is specified, use that always
b) otherwise, lookup up the _jabber._tcp or _xmpp-client._tcp for the
   domain part of the username.
c) finally, try the A record for the domain part.

Thanks,

Bron.