SOLVED Sendmail and Exim not working

Hi,

I have recently set up WHM on a cloud server, and I am having problems sending mail. I do not receive notifications from cPanel, and sendmail does not work at all. I have a web site running but without mail functions including php mail, but the DNS servers are OK and I can traceroute domains. If I run the mail troubleshooter on an email address, it reports the correct lookup host.
In WHM the mail queue has every email in it that has been sent so far. The mail delivery reports are either 'retry timeout exceeded', 'connection timed out', or 'retry time not reached for any host after a long failure period'.

If I try to use sendmail from the command line, I get this in exim_mainlog:

Code:

2017-02-01 16:10:18 1cYxUA-0009rM-Fh ** richard@domain.co.uk <root@whm.server.tld> R=dkim_lookuphost T=dkim_remote_smtp: retry time not reached for any host after a long failure period
2017-02-01 16:10:18 1cYxUA-0009rM-Fh Frozen (delivery error message)

I have changed the Exim listening port from 25, although I don't see how this would cause a problem sending mail. Apart from that, everything is still in the default configuration when WHM was set up.
Any help would be greatly appreciated.​

 

Thanks, I tried telnet on port 25 which I know is blocked, didn't work but I could telnet on port 587. I've already added that port to 'Exim Mail Server (on another port)' in WHM and opened the port in the server firewall. This is what I got from telnet:

Connected to mx1.server.com.
Escape character is '^]'.
220 antispam3.server.com ESMTP Exim 4.86-111764 Wed, 01 Feb 2017 17:10:54 +0000

​

So I assume the port is not an issue? Or does it have to be 25 to send mail out?

 

Thanks for the link which explains the problem very well. I have had my hosting company remove the block on port 25 and now email is sending from the server. However, when I use mail from the console to send an email, I get this error '550-Sender has no A, AAAA, or MX DNS records. whm.hostname.co.uk'. Here is the output from mail:

Code:

LOG: MAIN
  cwd=/ 5 args: send-mail -i -v -- [EMAIL]me@domain.com[/EMAIL]
LOG: MAIN
  <= [EMAIL]root@whm.hostname.co.uk[/EMAIL] U=root P=local S=508 T="test"
[root@whm /]# LOG: MAIN
  cwd=/var/spool/exim 4 args: /usr/sbin/exim -v -Mc 1cZFHx-0001Zb-Sk
delivering 1cZFHx-0001Zb-Sk
Connecting to mx1.spamfiltering.com [72.249.150.158]:25 ... connected
  SMTP<< 220 antispam3.spamfiltering.com ESMTP Exim 4.86-111764 Thu, 02 Feb 2017 11:10:55 +0000
  SMTP>> EHLO whm.hostname.co.uk
  SMTP<< 250-antispam3.spamfiltering.com Hello whm.hostname.co.uk [77.68.8.55]
         250-SIZE
         250-8BITMIME
         250-STARTTLS
         250-PRDR
         250 HELP
  SMTP>> STARTTLS
  SMTP<< 220 TLS go ahead
LOG: MAIN
  [72.249.150.158] SSL verify error: certificate name mismatch: "/OU=Domain Control Validated/OU=Hosted by UNITED COMMUNICATIONS LIMITED/OU=COMODO SSL/CN=antispam1.spamfiltering.com"
  SMTP>> EHLO whm.hostname.co.uk
  SMTP<< 250-antispam3.spamfiltering.com Hello whm.hostname.co.uk [77.68.8.55]
         250-SIZE
         250-8BITMIME
         250-PRDR
         250 HELP
  SMTP>> MAIL FROM:<root@whm.hostname.co.uk> SIZE=1546
  SMTP<< 250 OK
  SMTP>> RCPT TO:<me@domain.com>
  SMTP<< 550-Sender has no A, AAAA, or MX DNS records. whm.hostname.co.uk
         550 whm.hostname.co.uk
  SMTP>> QUIT

All the outgoing emails are frozen in the mail queue with the error '550-Sender has no A, AAAA, or MX DNS records. whm.hostname.co.uk'. But in the DNS zone for whm.hostname.co.uk, there is an A entry (points to the server IP) and an MX entry (just points to the FQDN of whm.hostname.co.uk)

The problem seems to be with the FQDN of the hostname, which in my case is something like whm.hostname.co.uk. If I run nslookup I get the following output:

Code:

[root@whm /]# nslookup whm.hostname.co.uk
Server:         x.x.x.x
Address:        x.x.x.x#53

** server can't find whm.hostname.co.uk: NXDOMAIN

But when I run it without the whm part, I get this:

Code:

[root@whm /]# nslookup hostname.co.uk
Server:         x.x.x.x
Address:        x.x.x.x#53

Non-authoritative answer:
Name:   hostname.co.uk
Address: x.x.x.x

Any help greatly appreciated.

 

Do I need to configure reverse DNS for BIND in WHM, as per this link?

 

Ah, missed an A entry on the hostname! With the port unblocked, email is now working. Thanks.