I have set up a postfix/dovecot/roundcube server on an Ubuntu box. Everything works fine *except* that my personal account on that machine cannot send mail to another account I have on a different machine. Instead, it's delivered back to the sender.
Specifically, if the account fp...@libertyfp.org sends mail to bi...@billoblog.com, the mail is delivered to fp...@libertyfp.org. This is specific to this particular pair. If I send email, for instance, from fp...@libertyfp.org to oli...@billoblog.com, it's delivered to oli...@billoblog.com. Mail *from* bi...@billoblog.com to fp...@libertyfp.org gets delivered fine. Here's what my syslog says: Aug 18 02:58:09 libertyfp postfix/qmgr[9675]: D0C4941E97: from=<fp...@libertyfp.org>, size=557, nrcpt=1 (queue active) Aug 18 02:58:09 libertyfp dovecot: lmtp(11707): Connect from local Aug 18 02:58:09 libertyfp dovecot: lmtp(fp...@libertyfp.org)<11707><+TFjIyFbHGG7LQAAHPmxyw>: msgid=<739649541ebad231caa0017671883c50c3810062.ca...@libertyfp.org>: saved mail to INBOX Aug 18 02:58:09 libertyfp postfix/lmtp[11706]: D0C4941E97: to=<fp...@libertyfp.org>, orig_to=<bi...@billoblog.com>, relay=mail.libertyfp.org[private/dovecot-lmtp], delay=0.96, delays=0.91/0.02/0.02/0.01, dsn=2.0.0, status=sent (250 2.0.0 <fp...@libertyfp.org> +TFjIyFbHGG7LQAAHPmxyw Saved) Aug 18 02:58:09 libertyfp dovecot: lmtp(11707): Disconnect from local: Client has quit the connection (state=READY) *********************************** The only recent change I made was to add a relay by sender line to main.cf to relay @gmail, @charter and @hotmail through billoblog.com. Apparently the vps I'm renting is in the middle of a bunch of dirty ip addresses and I get blacklisted by association every few weeks and have to appeal to get whitelisted again. Rather than deal with that, I decided to relay those addresses through another server of mine that is assigned an ip address in a better neighborhood. So... Here's what I added to main.cf: #ADDED 08/10/2021 to relay mail to gmail through billoblog sender_dependent_relayhost_maps = hash:/etc/postfix/bysender and here's what's in /etc/postfix/bysender % more bysender *@gmail.com [mail.billoblog.com]:25 *@hotmail.com [mail.billoblog.com]:25 *@charter.com [mail.billoblog.com]:25 I can't figure out if this is a postfix issue or a dovecot issue. Any pointers would be appreciated. billo