How to configure sendmail.postfix to relay on exchange 2010?

Question

I'm currently trying to figure out how to configure sendmail.postfix in Red Hat 6 to work with exchange 2010 relay. I've already configured our exchange server to allow our web server to relay. What are the commands to do so?

Solution

To use the postfix relay function, modify your /etc/postfix/main.cf file to include the following configuration:

queue_directory = /var/spool/postfix
command_directory = /usr/sbin
daemon_directory = /usr/libexec/postfix
data_directory = /var/lib/postfix
mail_owner = postfix
mydomain = domain.com
myorigin = $myhostname
inet_interfaces = localhost
inet_protocols = all
mydestination = $myhostname, localhost.$mydomain, localhost
unknown_local_recipient_reject_code = 550
relayhost = exchange2010.domain.com
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
debug_peer_level = 2
debugger_command =
         PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin
         ddd $daemon_directory/$process_name $process_id & sleep 5
sendmail_path = /usr/sbin/sendmail.postfix
newaliases_path = /usr/bin/newaliases.postfix
mailq_path = /usr/bin/mailq.postfix
setgid_group = postdrop
html_directory = no
manpage_directory = /usr/share/man
sample_directory = /usr/share/doc/postfix-2.6.6/samples
readme_directory = /usr/share/doc/postfix-2.6.6/README_FILES

Where the key entires that will need modifying to suit your local settings are:

mydomain = domain.com

Set this to your local domain.

myorigin = $myhostname

If you want the mail to originate from the hostname of the client.

relayhost = exchange2010.domain.com

This is the FQDN of your exchange server.

Then reload / restart your postfix service:

service postfix reload / restart

Comments

[geedoubleya]

No problem, if this works for you then accept it as the answer to avoid other users spending time on the solution.

[Ricardo]

Hey Geeoubleya question for you yesterday I made all the changes on the our web server but I'm still getting the SMTP error on the website. What else should I look? On the exchange server I've tested the relay using putty and I don't get any errors. Please Advice

[geedoubleya]

@Ricardo Does echo Test email | mailx -v -s "Test Email" email@address work?

[Ricardo]

No it doesn't work. I've also tried to make the changes on joomla and I still can't send mail. I tripple checl the exchange server as well and I can send test email back and fourth via powershell. Any more ideas??

[Mike]

@Ricardo It could be the exchange server force to have e.g an authenticated user?