> > You cannot depend on "first DNS" setting on a client -- most DNS > > clients may try ANY of the one's listed -- Windows clients for > > instance certainly work this way. > > OK, fair enough (although from my experience, dig always > seems to take the first one it finds that works). So I took > all other entries out of /etc/resolve.conf on the SMTP(spamc)
Dig has/is it's own resolver if I recall correctly. > Linux telnet has this kind of thing? Where is it?? I > thought that is what /etc/resolve.conf is. Telnet uses the built-in resolver -- most ordinary applications work this way. > > You should generally point clients to ONE CONSISTENT (set of) DNS > > servers which return all the correct answers the client > > will ever need. If the DNS server (set) doesn't know the > > answer it must forward or recurse to find it. > > Well, since the ultimate client will be spamc, what does spamc use? > Something other than /etc/resolve.conf? Most (almost all) regular applications use the built-in resolver but IIRC SpamC has this as a configuartion/ environemnt setting so it (this is true for SpamAssassin and Net::DNS actually) might be using a different setting for DNS than the computer as a whole. > Also, will my local IP addresses in my zone file get > propagated to other DNS servers? (If what you say about > consistency is important, and I put more than one nameserver > in /etc/resolve.conf, I will want to make sure they propagate > to the other DNS servers). It will propagate to all Secondary DNS servers that hold that SAME zone (notice that a Secondary DNS server is only Secondary for one zone at a time -- it might be Primary for other zones, and of course doesn't hold every possible zone.) So if your zone is mydomain.com with spam.mydomain.com being a resource record in that zone, then every DNS server that holds mydomain.com (i.e., is authoritative for mydomain.com) will have that record replicated to it (if everything is working reasonable ok.) -- Herb Martin
