redhat 7.2: sendmail does not work with outgoing mail

[Guest_imported]

Hi all:
i just upgraded to redhat 7.2 and configure sendmail. Now i can deliver mail locally and receive email from outside world, but never deliver mail to the outside.

<<< 551 5.5.1 Mail rejected
554 5.0.0 Service unavailable
....
Diagnostic-Code: SMTP; 551 5.5.1 Mail rejected

I've consulted all the forums and read all the documentation and made all the changes i think i was able to make (including changing the DAEMON_OPTIONS that came by default, changing de ip address from loopback to my public ip address). Alse i've installed webmin to make all the changes easier!!

Someone could help with this?
Alse there is a machine in the network with an MX record pointing to this redhat 7.2 machine of mine.

Thanks a lot !

 

[jollyroger]

Not entirely sure, but some SMTP daemons (I call them this because I mean all the machines you are sending mail to) require the ability reverse lookup an IP address. I know you said there was an MX record, but is there a lookup for your IP address.
Best of luck if this is set up OK.
With regards
Ben

 

[ifincham]

Hi,

A 551 error message means 'user not local' but is also used by smtp servers in denying relaying. This is where the receiving smtp server is not convinced it is talking to the authentic smtp server for the origin domain of the email - for example if a dial-up linux user uses sendmail locally with an email address from their ISP then theres a good chance that would be bounced by the other end because it didn't originate from the ISP's smtp server.

You'd need to make sure the outbound email was set to from whoever@your_domain and that the IP address resolves correctly to that domain - e.g. by something like :

$ host 202.1.1.1

The 'features' in sendmail.mc are documented here -->

http://www.sendmail.org/m4/features.html

Also, have a look at the redhat howto & faq -->

http://www.redhat.com/support/resources/mail_news/mail.html

Regards

 

[Guest_imported]

Hi guys:
finally i've discovered the problem was that the machine that has a MX record pointing to me, so i was supposed to relay through, is not doing that work correctly. I don't know why because it is managed by other people who swear the problem was the configuration of my sendmail server

Now i can relay e-mail through another machine of mine

Thanks a lot.