can no longer send mail from one server to the other

audrey

Well-Known Member
Oct 18, 2006
129
6
168
Two of my servers that are at the same datacenter were rebooted and
I can no longer send mail from one server to the other.

sending mail works great on both servers as long as I do not try to send mail to an account on the other server. (in other words - I can send mail to gmail or hotmail or aol - just not the other server)

receiving mail is not a problem on either server

this is the error in the mail logs on both servers
R=lookuphost T=remote_smtp defer (-53): retry time not reached for any host

Any advice to solve this problem would be greatly appreciated

Thanks
Audrey
 

cPanelTristan

Quality Assurance Analyst
Staff member
Oct 2, 2010
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Hello Audrey,

Please try clearing the exim databases that handle the retry times:

Code:
/usr/sbin/exim_tidydb -t 1d /var/spool/exim retry > /dev/null 
/usr/sbin/exim_tidydb -t 1d /var/spool/exim reject > /dev/null 
/usr/sbin/exim_tidydb -t 1d /var/spool/exim wait-remote_smtp > /dev/null
Then restart exim at that point. What likely happened is that the two machines couldn't reach each other and now won't try to send mail until the retry time is reached.

Also, can you telnet on each machine to the other machine on port 25 at this time?

Code:
telnet othermachineIP# 25
Thanks.
 

audrey

Well-Known Member
Oct 18, 2006
129
6
168
Thank you so much for your quick response!

Unfortunately it did not solve the problem on either server

One of the servers can telnet to the other and the other server cannot
 

cPanelTristan

Quality Assurance Analyst
Staff member
Oct 2, 2010
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Do you have a firewall running on both servers? Can you try taking the firewall down and re-attempt the telnet on the machine?
 

audrey

Well-Known Member
Oct 18, 2006
129
6
168
one more thing- I restarted exim in the whm as opposed to ssh
Do you think that I should stop and start exim in ssh?
Thanks again
 

cPanelTristan

Quality Assurance Analyst
Staff member
Oct 2, 2010
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It is fine to restart it via WHM rather than root SSH, although I normally perform the restart in SSH myself.
 

audrey

Well-Known Member
Oct 18, 2006
129
6
168
Thanks again for the quick response
and thanks for letting me know restarting in whm being ok

the one server has the csf firewall
I turned it off and the other server can now telnet to the one with the csf firewall.
So with this csf firewall turned off - both servers can telnet to each other

the other server just has the firewall that is standard on a linux machine.
I do not know how to turn it off.

I tested the email again bn both servers sending to each other when the firewall was off and still no luck - same error
 

cPanelTristan

Quality Assurance Analyst
Staff member
Oct 2, 2010
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You'll have to reclear the database files again and restart exim again, then re-try it now with the firewall turned off.
 

audrey

Well-Known Member
Oct 18, 2006
129
6
168
I turned off the csf firewall again
and with the csf firewall turned off
I cleared the databases again on both servers
and I stopped and started exim in ssh on both servers
and I still get the same error in the maillogs when I try to send mail from server to server
 

cPanelTristan

Quality Assurance Analyst
Staff member
Oct 2, 2010
7,607
43
348
somewhere over the rainbow
cPanel Access Level
Root Administrator
Could you try opening up a ticket with us so we can check into this further? Clearing those databases should allow the timeout to be cleared. You can use WHM > Support Center > Contact cPanel or the link in my signature.