[jdev] Second-guessing dns for s2s

[Stephen Marquard]

Matt Tucker wrote:
> Richard,
> 
>>Interesting solution but not exactly standard, and will only 
>>work between servers that are running Jive Messenger,
> 
> True. However, the nice thing about the logic is that normal DNS is
> tried first. We also recommend that users setup DNS for max
> compatibility. Even so, the extra logic means that if normal DNS isn't
> or can't be setup, the service will still work if the other server is
> JM. So far, we don't see a reason that this couldn't be added as an
> implementation recommendation attached to the RFC's.

This really sounds like a bad idea to me. This implies that in the case of user 
error, for example a user who tries to connect to a service such as 
conference.uct.ac.za, a JM server will try to resolve and connect to uct.ac.za 
and then ac.za ? Just moving up the tree isn't a reasonable assumption.

Instead of 1 NXDOMAIN dns lookup result, you have either 3 failed lookups, or 
perhaps worse, 2 failed connection attempts to resolvable addresses which have 
no jabber servers running there, or perhaps completely unrelated servers (in 
which case the failure gets even messier).

This is bad engineering i.t.o. creating undesirable impact on the broader Internet.

Regards
Stephen