New version of mod_epp released

I finally manged to crank out a new release of mod_epp. So, what’s new?

Last November Gavin Brown sent me a bug report regarding the handling of large answers. I provided a quick fix back then but did no official release.

While debugging that issue, I noticed that mod_epp didn’t generate the greeting on newer apaches. Tracing that, I found that the kernel didn’t return from accept on connection open, but on the first data reception. First I suspected the epoll interface, but some more intensive debugging found a more mundane reason: setsockopt is used to set:

TCP_DEFER_ACCEPT

Allows a listener to be awakened only when data arrives on the socket. Takes an integer value (seconds), this can bound the maximum number of attempts TCP will make to complete the connection.

Some more googling found the answer: you need to use the AcceptFilter directive to disable this optimization for the EPP socket.

This is not really documented, thus this bug report.

Watching logfiles with Cacti

Assume you have a number of patterns you might want to watch out for in various logfiles. These could be harmless, e.g. postfix/smtp\[[[:digit:]]+\]: .* status=sent which indicates that a mail was sent by postfix, or could be bad, e.g. indications of hardware troubles, firewall log entries or suspicious entries in proxy logs.

There are a number of tools which can help you do that, e.g. logwatch can produce nice reports for you.

In my case, I was less interested in individual log entries, but in a graphical representation of their frequency. For that, I need something similar to MRTG. Cacti is a decent graphical frontend to the core MRTG engine, rrdtool. It provides various data sources and graphing options all packed up into a neat web interface.

So, what needs to be done to get Cacti to graph match-rates of regexs in logfiles?

Continue reading Watching logfiles with Cacti

Please welcome: Elena

Just in case somebody was wondering why my blogging was non-existent recenty:

Elena

Born on May 22th, she certainly made my life even more interesting and, in close coordination with Clemens, the two children manage to consume my energy and spare time.

Up to date picture are at my gallery.