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March 2, 2022 – 2:00 pm

Books have been written on the subject of awk and sed. Here’s a small sample of commands I put together over the years that are useful for everyday system administration tasks. Most of these tasks …

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Articles in Postfix

Saving Postfix Messages

June 3, 2015 – 3:08 pm
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Sometimes for testing purposes you need to save all messages going through Postfix active queue. There are a couple of ways of doing this.

Verify Email SSL Certificate from CLI

May 8, 2015 – 10:36 am
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Just a quick reference for validating SSL certs on mail servers. This is not something I have to do often, but when the need arises, I find myself googling the answer every single time. So …

Using Pflogsumm Postfix Log Analyzer

December 4, 2014 – 12:29 am
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Pflogsumm is an oldie but a goodie. It’s a Perl script that sifts through your Postfix server maillog and provides you with a neat summary of events and some statistics. This information can be useful …

Searching Log Files

April 18, 2014 – 4:40 pm
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This is a quick example of finding the first and last occurrence of an event in the log file. This can be useful for determining the service outage window and for general troubleshooting. In the example below I am looking at the PostFix maillog file, trying to figure out the duration of the problem I’ve been having with one of the mail relay servers.

Watch the Log

June 18, 2013 – 8:06 pm
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In the past few days my Postfix server has been having occasional problems talking to the mail gateway. They problem would come and go. The Postfix server would timeout trying to connect to the gateway and keep …

Install Pflogsumm PostFix Log Summarizer

March 12, 2013 – 9:58 am
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Pflogsumm is yet another log analyzer/summarizer for Postfix. It is written in Perl and has been around for a while. Very simple to install, so I writing this post mostly as a note to myself. I added an example cron job with some “grep” syntax to cut the Pflogsumm report down to size by dropping some things I am usually not interested in.

Installing Sendmail Analyzer on RHEL/CentOS

March 11, 2013 – 11:35 pm
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The Sendmail Analyzer can be useful for visualizing your Sendmail/Postfix log. The commands below can be copy-pasted as root on default installations of RHEL and CentOS 5/6 with default Postfix and httpd. If your configuration …