(http://www.faximum.com/technotes/236)
****** BETA - DRAFT *** BETA - DRAFT *** BETA - DRAFT *** BETA - DRAFT ****** TITLE: #236 - Configuring Sendmail on Red Hat 7.2 KEYWORDS: sendmail red hat redhat rhs RELEASE: Faximum Messaging Server 2 CLASSIFICATION: Any-FMS PROBLEM: During pre-installation testing it has been determined that the Red Hat 7.2 system is not configured to accept email from external systems. This is feature is needed if the RHS system is going to be used to accept email from other systems to be delivered by fax. There are several areas that need to be checked to ensure that your system can accept external email. This technote outlines steps to check and reconfigure your email server. SOLUTION: 0) To test to see if a server is accepting external email please run telnet from another system on the same network. For example, if the IP address for the server in question is 1.2.3.4 then you can test by running the following command: telnet 1.2.3.4 25 (This will work on Linux, UNIX, Windows, and Mac OS X.) If the server is accepting email then you will see a line that starts with "220" and contains the letters "SMTP". Type QUIT to exit. If the server is not accepting email then you will receive an error message from telnet. 1) Check that sendmail or postfix has been installed on your system by running: rpm -q sendmail and rpm -q postfix If sendmail is installed you will see a response similar to: sendmail-8.11.6-3 If postfix is installed you will see a response similar to: postfix-20010228-1 If neither mail server is installed on your system (if you get a response similar to "package xxxx is not installed") then please consult your documentation to determine how to install the sendmail package. If you have postfix then please contact Faximum Technical Support (support@faximum.com) for guidance (this Technote only applies to sendmail on Red Hat 7.2). 2) Check to see if sendmail is listening on the SMTP port 25. Run the following: netstat -an | grep :25 If you get no output then sendmail is not running and you need to address that problem before proceeding further. If you see a line similar to the following: tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN then sendmail is properly configured and you can proceed to step xx below. If you see a line similar to the following: tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN then sendmail has been configured to ignore outside connections. Please proceed to step 3. 3) If sendmail is configured to listen only on 127.0.0.1 then please edit the sendmail.cf file (usually found in /etc) and look for a line of the form: O DaemonPortOptions=Port=smtp,Addr=127.0.0.1, Name=MTA and comment it out by putting a # in the first column: # O DaemonPortOptions=Port=smtp,Addr=127.0.0.1, Name=MTA Then restart sendmail by running: /etc/rc.d/init.d/sendmail restart After doing this repeat the test in step #2 to verify that sendmail is now listening on 0.0.0.0 4) Look at the contents of the file /etc/sysonfig/ipchains for a line like: -A input -s 0/0 -d 0/0 25 -p tcp -y -j ACCEPT If the file does not contain such a line then add it as the first of the lines that start with a "-A". After editing the file then run: /etc/rc.d/init.d/ipchains restart 5) At this point try running the test in step 0 (above) again to verify that your system is now accepting external email requests. If it is not, please contact Faximum Technical Support (support@faximum.com) for further assistance. TechNote: 236 - Copyright 2002 Faximum Software Inc., All Rights Reserved. Last Updated: Wed Mar 6 00:28:02 PST 2002 Find all Faximum TechNotes at http://www.faximum.com/support© Copyright 2001 Faximum Software Inc. All Rights Reserved.