My laptop, which comes up fine at home, won't come up in a hotel room
unless I disconnect the ethernet cable. The hang seems to happen
while trying to bring up the avahi daemon. I think this problem has
something to do with the fact that in hotel rooms, you can't do
anything on the Internet before you log in to some proxy server. (At
home I have a router that just lets any system plugged into it connect
no-questions-asked.)

I know I can get around this by disabling avahi (insserv -r avahi-
dnsconfd) but avahi is actually useful to me at home and besides that
I'd like to pose this more general question about avahi: is there a
way to make configure it to just give up, if after say 15 seconds it
hasn't found whatever it's looking for?