Client host rejected: cannot find your hostname Exchange 2010
Posted on 2013-08-28
So we started getting some rejected messages now for a couple of places we have been sending to in the past. I'm hoping to get some help in fixing this and ensuring that everything is configured properly.
Barracuda Anti-Spam device
I control DNS with ZoneEdit
My domain is mydomain.com
My public ip address is 18.104.22.168
My internal server name is server1.mydomain.local
I need to figure out how to fix this properly once and for all. I have been messing around with setting a PTR record via zoneedit but it is not working.
Do I need to change anything in the barracuda, exchange, my local DNS, zoneedit? Everywhere?
I have a PRT record in Zone Edit, 22.214.171.124.in-addr.arpa directed to server1.mydomain.com
My MX points to mail.mydomain.com
Why is the SMTP results showing barracudaAS.mydomain.com as the name? Is that being read from the Barracuda itself?
Results from MXTOOLBOX
220 barracudaAS.mydomain.com ESMTP (6bc1508cda5c946c14ed1c294d33d62a) [796 ms]
250-barracudaAS.mydomain.com Hello mxtb-pws3.mxtoolbox.com [126.96.36.199], pleased to meet you
250 HELP [686 ms]
MAIL FROM: <email@example.com>
250 Sender <firstname.lastname@example.org> OK [702 ms]
RCPT TO: <email@example.com>
550 No such domain at this location [702 ms]
SendSMTPCommand: You hung up on us after we connected. Please whitelist us. (connection lost)