* "Dr. Lars Hanke" <l...@lhanke.de>: > I had a quite strange issue. About a week ago my bind9 broke down and I > could not get it running again on the same machine. So moved it to > another machine and changed the /etc/resolv.conf of my machines to try > both IP. Apparently everything worked fine. > > Today I was puzzled that the corresponding bug-report to the Debian list > was somehow missing. I resent it watching the postfix logs and found > that potfix was missing the MX entry of my relay host and refused to > send. Since the host itself actually does not have a MX entry, I was > sidetracked assuming postfix was not smart enough to strip the host name > from the domain. During this trouble shooting I had postfix reload its > configuration a couple of times. After setting the name in [] postfix > reported that the A entry was missing, which definitely was wrong. > > I restarted postfix and voilá it continued working like it did all the > years before. Now I know that it is smart enough to strip the relay host > name from the domain to lookup MX. ;) > > Apparently postfix missed the switching of nameservers and did not learn > of the new DNS until restart. Is this a bug or a feature? > > Postfix Version: 2.5.5 (Current Debian stable)
The Debian packages of Postfix are running smtpd in a chroot by default. The files necessary for this are copied by the init script /etc/init.d/postfix - and amongst them is the resolv.conf you changed. I guess what happened is: 1. You didn't disable smtpd's chroot in master.cf. 2. You changed /etc/resolv.conf without copying it to the chroot. 3. You restarted Postfix using Debian's init script which copied the changed resolv.conf file to the chroot. Stefan
