SMTP and POP port in my server is blocked by firewall for security
reason. In order for me to send out message from my sendmail, I need
to forward all outgoing email to another mail server within the
network. Only that server got open SMTP port to outside.

I am using RHES3 and sendmail-8.12.10

Kindly please advise how I can setup this? I believe it is something
to do with the sendmaiil.mc file is it?

Thank you.

Earnpin Lee
pin@1.com.my

Go to the file /etc/mail/sendmail.mc and uncomment the line that looks like this:

dnl define(`SMART_HOST',`smtp.your.provider')

To uncomment it you have to remove the "dnl " text. Also, change
"smtp.your.provider" to the real host that you want to use as your
relay.

Save the file and then execute the following command:

make -C /etc/mail

I'm not sure if you have to restart sendmail after this, but it can't hurt:

/sbin/service sendmail restart

After these changes, all your outgoing mail should be going through
the host specified.

Vladimir

Yes - you will have to restart sendmail, and rebuild.

Basically this is the same information that vladimir provided, but
you'll have a backup just in case you make a mistake.

It's always safe to shutdown the process while doing this :

service sendmail stop (or /sbin/service - depends on how you have your
server configured)

1) cp /etc/sendmail.cf /etc/sendmail.cf.old
   This command copies your current sendmail configuration and saves it as
   sendmail.cf.old.

2) cp sendmail.mc sendmail.mc.original
   This copies your sendmail.mc file.

3) pico sendmail.mc
   Pico allows you to edit the file. You may have 'vi' vice pico - either will
   work just as well.

4) Edit the line noted by vladimir - then save.

5) m4 sendmail.mc > /etc/sendmail.cf
   Rebuilds sendmail.cf

Then you can safely restart sendmail - service sendmail restart.
Should any problems arise - you can safely roll back to your old
configuration by rebuilding with the original configuration file.

-SgtCory

The other comment posters are correct, but you may need to install the
sendmail-cf rpm to utilize the .mc approach.  If you do not already
have that rpm installed, and do not wish to install it, you can add
your SMART_HOST definition directly into the /etc/mail/sendmail.cf
file yourself.  Open /etc/mail/sendmail.cf in your favorite editor and
search for the DS definition.  By default it will be blank.  To add
your SMART_HOST simply add the DNS name directly after 'DS' (without
any space, i.e.  DSsmtp.your.provider).  Save and close the file and
restart sendmail.

Hope this helps.

Michael Kidd