NO JOY Can't get sendmail working.

[RoboLord]

I had a rock solid instance of IncrediblePBX going until a few months ago when all email from both the voicemails and from AvantFax just stopped arriving. It was a basic install on a Raspberry Pi. Thinking I screwed something up or the SD card got corrupted, I decided to try a fresh install on a different machine, however I had the same problem on the new install so I decided to dig a little deeper.

I tried sending a test email from the command line with sendmail and discovered that my ISP (Comcast) is rejecting my mail because it's coming from an invalid domain.

"reason: 550 5.1.0 <[email protected]> sender rejected : invalid sender domain"
​

I read through a bunch of posts on this forum, some from 2008, some newer, and tried changing a lot of settings but never got it sorted out. Some of the suggestions relied on files that have changed names or moved locations. I've reached the point of asking for help.

I tested with telnet to see if port 25 is blocked, it is not.
I changed /etc/mail/sendmail.cf to include comcast (DSsmtp.comcast.net), no luck, and no change to the error message.
I edited my hosts file and, voicemail.conf, no change.

It seems like there is something simple I missed here and I can't understand why it used to work on my old machine and then just stopped.

Can anyone give an up to date guide for setting up email from a stock install? My details are IncrediblePBX13-13.iso running in a VM on Proxmox on a NUC. I have a 3CX install in another VM and it sends emails just fine. Thanks!

 

[RoboLord]

I did these steps beyond the initial install and was able to get rid of the error messages from Comcast and Gmail in "/var/spool/mail/root",

edit "/etc/hosts" file to add "domain.duckdns.org"
edit "/etc/mail/sendmail.cf" to add "DSdomain.duckdns.org"
edit "/etc/asterisk/voicemail.conf" to add "[email protected]"

the tutorial calls for editing "/etc/asterisk/vm_general.inc" but this file doesn't exist on my install
the tutorial calls for running "setup-mail" but this command does not exist on my install

Error messages go away but mail still doesn't arrive. What else do I need to do? Here's the full readout from a sendmail test:

root@IncrediblePBX:~ $ echo "Subject: sendmail test" | sendmail -v [email protected]

[email protected]... Connecting to [127.0.0.1] via relay...
220 domain.duckdns.org ESMTP Sendmail 8.14.4/8.14.4; Thu, 12 Jul 2018 02:32:00 -0700
>>> EHLO mobilityproject.duckdns.org
250-domain.duckdns.org Hello domain.duckdns.org [127.0.0.1], pleased to meet you
250-ENHANCEDSTATUSCODES
250-PIPELINING
250-8BITMIME
250-SIZE
250-DSN
250-ETRN
250-DELIVERBY
250 HELP
>>> MAIL From:<[email protected]> SIZE=23
250 2.1.0 <[email protected]>... Sender ok
>>> RCPT To:<[email protected]>
>>> DATA
250 2.1.5 <[email protected]>... Recipient ok
354 Enter mail, end with "." on a line by itself
>>> .
250 2.0.0 w6C9W0G9027272 Message accepted for delivery
[email protected]... Sent (w6C9W0G9027272 Message accepted for delivery)
Closing connection to [127.0.0.1]
>>> QUIT
221 2.0.0 domain.duckdns.org closing connection​

 

[RoboLord]

I finally made this work:

edit "/etc/hosts" file to add "domain.duckdns.org"
edit "/etc/mail/sendmail.cf" to add "DSsmtp.comcast.net"
edit "/etc/asterisk/voicemail.conf" to add "[email protected]"