Dealing with "unexpected RCODE (SERVFAIL)"

[Ruben Laban]

Hello list,

In my logs I see numerous line like these:

Mar 16 04:59:13 mx02 named[4606]: unexpected RCODE (SERVFAIL) 
resolving 'hotmeil.com/MX/IN': 10.2.1.3#53
Mar 16 04:59:14 mx02 named[4606]: unexpected RCODE (SERVFAIL) 
resolving 'hotmeil.com/MX/IN': 10.0.1.3#53
Mar 16 04:59:15 mx02 named[4606]: unexpected RCODE (SERVFAIL) 
resolving 'hotmeil.com/MX/IN': 10.1.1.3#53

The hostname that's being tried to resolve obviously has a typo in it, users 
tend to make such mistakes a lot.

In our case mx02 runs it own caching nameserver, which uses our internal 
caching nameservers (10,[012].1.3) as forwarders.

Is there something I can change in the configuration of either (or both) mx02 
or 10.[012].1.3 to prevent "the unexpected"?

Is it safe to ignore these error completely (either in our filters or in 
bind's configuration)? I'm a bit hesitant to do so, since I got the feeling 
that I might miss out on actual problems occuring (other than users not being 
able to spell).

I google'd around several times, but could never find any useful information 
on this subject.
-- 
Regards,

Ruben Laban
Senior Systems and Network Administrator
ISM eCompany