Sendmail/'host name lookup failure'

[Lowell Gilbert]

Jeff Gentry <freebsd at hexdump.org> writes:

> The other day I rebooted my FreeBSD machine.  Ever since then, messages to
> hotmail.com and yahoogroups.com are not going through - the mail logs
> report that there is a 'host name lookup failure' to the specific MX
> hosts (eg 'mx1.hotmail.com').  The thing is though, I can run dig/nslookup
> on these hotsnames perfectly fine - in fact I can even telnet to port
> 25 of all of these hostnames, issue a HELO, etc.
> 
> Does anyone have an idea what might be going on here?

I'm taking a shot in the dark here since you didn't post the full log
message, but is it maybe its own hostname that it can't look up (or
perhaps the other end can't find it)?

Or maybe these are transient problems for specific other mail hosts?