Not sending or receiving emails

Hi Everyone,

Got an issue with postfix. It is not sending or receiving emails. I don't get a bounce back, just the emails not coming in or going out.

Let me know what you need to help with the issue.

Here is info from the log file:

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Jan 21 19:51:11 host postfix/smtpd[94956]: connect from mail-lf1-f44.google.com[209.85.167.44]
Jan 21 19:51:11 host postfix/smtpd[94956]: TLS SNI mx.mydomain.ca from mail-lf1-f44.google.com[209.85.167.44] not matched, using default chain
Jan 21 19:51:11 host postfix/smtpd[94956]: Anonymous TLS connection established from mail-lf1-f44.google.com[209.85.167.44]: TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256
Jan 21 19:51:12 host postfix/smtpd[94956]: NOQUEUE: reject: RCPT from mail-lf1-f44.google.com[209.85.167.44]: 554 5.7.1 Service unavailable; Client host [209.85.167.44] blocked using zen.spamhaus.org; Error: open resolver; https://check.spamhaus.org/returnc/pub/172.69.207.5/; from=<my gmail@gmail.com> to=<doug@mydomian.ca> proto=ESMTP helo=<mail-lf1-f44.google.com>
Jan 21 19:51:12 host postfix/smtpd[94956]: disconnect from mail-lf1-f44.google.com[209.85.167.44] ehlo=2 starttls=1 mail=1 rcpt=0/1 bdat=0/1 quit=1 commands=5/7
Jan 21 19:51:34 host postfix/smtpd[94956]: connect from mail-ej1-f48.google.com[209.85.218.48]
Jan 21 19:51:34 host postfix/smtpd[94956]: TLS SNI mx.daowen.ca from mail-ej1-f48.google.com[209.85.218.48] not matched, using default chain
Jan 21 19:51:34 host postfix/smtpd[94956]: Anonymous TLS connection established from mail-ej1-f48.google.com[209.85.218.48]: TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256
Jan 21 19:51:34 host postfix/smtpd[94956]: NOQUEUE: reject: RCPT from mail-ej1-f48.google.com[209.85.218.48]: 554 5.7.1 Service unavailable; Client host [209.85.218.48] blocked using zen.spamhaus.org; Error: open resolver; https://check.spamhaus.org/returnc/pub/108.162.240.5/; from=<mygmail@gmail.com> to=<doug@mydomain.ca> proto=ESMTP helo=<mail-ej1-f48.google.com>
Jan 21 19:51:35 host postfix/smtpd[94956]: disconnect from mail-ej1-f48.google.com[209.85.218.48] ehlo=2 starttls=1 mail=1 rcpt=0/1 bdat=0/1 quit=1 commands=5/7
Doug

Are you in Toronto? Spamhaus is showing open resolver and is listing 2 different IP addresses. What is your domain name?

what is the domain name & the base IPv4 of the server?
So we can lookup to see if there are problems.

Server is located in Toronto.

Spamhaus is not activated at this time

Server IP: 38.99.139.101 | host.daowen.ca

Domains:

daowenpublications.ca
daowen.ca
mmtproductions.ca
mymassagetherapist.ca

There is no SSL for your hostname.
Try to get that part fixed, Rebuild the mail server, Restart All the mail services (button on bottom), or you can manually restart Postfix, Dovecot, ClamAV, AMaViS, OpenDKIM, SpamAssassin, and try to send mail again after.

cd /scripts
sh generate_hostname_ssl
sh cwpsrv_rebuild_user_conf

--

Other than that.

https://multirbl.valli.org/lookup/38.99.139.101.html - Is listed on 1 RBL, not bad.

Listed at: https://matrix.spfbl.net/38.99.139.101

https://multirbl.valli.org/lookup/host.daowen.ca.html - Hostname is clean

I appreciate your time and help.

Still facing the error. Here is the excerpt from the log file:

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Jan 22 10:31:50 host postfix/smtpd[146848]: connect from mail-ej1-f45.google.com[209.85.218.45]
Jan 22 10:31:51 host postfix/smtpd[146848]: TLS SNI mx.daowen.ca from mail-ej1-f45.google.com[209.85.218.45] not matched, using default chain
Jan 22 10:31:51 host postfix/smtpd[146848]: Anonymous TLS connection established from mail-ej1-f45.google.com[209.85.218.45]: TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256
Jan 22 10:31:51 host postfix/smtpd[146848]: NOQUEUE: reject: RCPT from mail-ej1-f45.google.com[209.85.218.45]: 554 5.7.1 Service unavailable; Client host [209.85.218.45] blocked using zen.spamhaus.org; Error: open resolver; https://check.spamhaus.org/returnc/pub/2400:cb00:29:1024::6ca2:f006/; from=<mygmailaccount@gmail.com> to=<me@daowen.ca> proto=ESMTP helo=<mail-ej1-f45.google.com>
Jan 22 10:31:51 host postfix/smtpd[146848]: disconnect from mail-ej1-f45.google.com[209.85.218.45] ehlo=2 starttls=1 mail=1 rcpt=0/1 bdat=0/1 quit=1 commands=5/7

Google is reporting that Spamhaus lists your IP as an open resolver -- did you look up the link Gmail was sending back to you for more information?

Your ports/firewall look correct, but I would suggest switching to https on 2031 for CWP as soon as you get your SSL certificate.

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Nmap scan report for host.daowen.ca (38.99.139.101)
Host is up (0.019s latency).
Not shown: 986 filtered ports
PORT     STATE  SERVICE
20/tcp   closed ftp-data
21/tcp   open   ftp
25/tcp   open   smtp
53/tcp   open   domain
80/tcp   open   http
110/tcp  open   pop3
113/tcp  closed ident
143/tcp  open   imap
443/tcp  open   https
465/tcp  open   smtps
587/tcp  open   submission
993/tcp  open   imaps
995/tcp  open   pop3s
2030/tcp open   device2PTR looks good, MX record in place (but why priority 30)?

Resolved!

Issue came up due to the name server. Prior, I used Googles name server, which Spamhaus has black listed. This caused the lookup of all IPs to reject, thus Spamhaus rejected the emails coming into the system. Resolved by changing the name server.

Thanks for you time investigating.

Well that's a new problem that opens a whole new can of worms.

I usually use Cloudlfare's DNS servers (1.1.1.1, 1.0.0.1). But best practice is to have DNS from multiple providers, such as Level3 (4.2.2.2) and Quad9 (9.9.9.9) -- chosen for reliability and ease of memory. Somehow I've always avoided using Big G's DNS servers for my servers -- fine for end user use (but even there I recommend OpenDNS or Cloudflare's filtering DNS 1.1.1.3, 1.0.0.3).
https://dnschecker.org/public-dns/us