Daniel Armando Rodriguez wrote:
> , relay=none, delay=1.2, delays=0.15/0.01/1/0, dsn=5.3.0, status=bounced
> (unable to look up host host.domain.com: No address associated with
> hostname)
>
> However, DNS resolution works as expected and has a PTR record associated
> with it.
It is very common for postfix to be run with a chroot configuration
specified in the master.cf file. It's the default for many software
distributions. Your description fits a case where you can look up the
name in the host system outside the chroot but postfix inside the
chroot cannot. You can check the configuration this way.
$ postconf -F smtp/unix/chroot
$ postconf -F relay/unix/chroot
The first thing I would try is stopping postfix and then starting it
again. Because many start up scripts sync the host DNS configuration
into the chroot at startup. This can "just fix it" for many of the
problems that might cause this. Try that first.
And the detail is that the /etc/resolv.conf file is copied into the
chroot location. In other words these two files should have the same
contents. And since it is a chroot the chroot version should be a
copy (not a symlink) to the main one outside the chroot.
$ echo diff /etc/resolv.conf $(postconf -h queue_directory)/etc/resolv.conf
diff /etc/resolv.conf /var/spool/postfix/etc/resolv.conf
$ diff /etc/resolv.conf $(postconf -h queue_directory)/etc/resolv.conf
...no output...same....no differences...
My best guess is that your chroot does not have a working resolv.conf file.
Bob
