November 2007
Beginner
642 pages
15h 43m
English
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19.14. Troubleshooting SMTP Servers
Problem
What are some tests you can run directly on your SMTP server to see if it is working correctly? You want to eliminate as many variables as you can, and talk directly to the server, if that's possible.
Solution
Good old telnet does the job. You also needthe mailx package installed, and Netstat.
First, run telnet on your SMTP server to see if you can talk to it. This example creates and sends a test message:
$ telnet localhost 25Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. 220 xena.alrac.net ESMTP Postfix (Ubuntu)ehlo xena250-xena.alrac.net 250-PIPELINING 250-SIZE 10240000 250-VRFY 250-ETRN 250-STARTTLS 250-ENHANCEDSTATUSCODES 250-8BITMIME 250 DSNmail from: carla@testing.net250 2.1.0 Okrcpt to: carla@xena250 2.1.5 Okdata354 End data with <CR><LF>.<CR><LF>Date: July 4, 2007 From: testcarla Reply-to: testcarla@testing.net Message-ID: one Subject: SMTP testing Hi Carla, If you can read this, the SMTP server works. .250 2.0.0 Ok: queued as B2A033FBA quit 221 2.0.0 Bye Connection closed by foreign host.
Now, run mail to read your
message:
& tMessage 1: From carla@testing.net Sun Jul 15 10:46:21 2007 X-Original-To: carla@xena.alrac.net Date: July 4, 2007 From: testcarla@xena.alrac.net Reply-to: testcarla@testing.net Subject: SMTP testing To: undisclosed-recipients:; ...
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