OpenSSL ist beständiger Quell der Verzweiflung für alle Netzwerk-Programmierer und Admins. Noch steigern lässt sich der Spaß aber mit zwei parallel installierten OpenSSL-Versionen (unter BSD häufig anzutreffen, weil das OS noch v0.9.x mitbringt und man sich dann ein v1.0.x aus den Ports dazuinstalliert).
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Falls er per (F)CGI eingebundene PHP-Interpreter viele “Internal Server Errors” verursacht, sich aber im Apache-Log keine Fehlermeldung findet… dann sollte man nachsehen ob die PHP-Prozesse überhaupt durchlaufen oder aber abstürzen.
Falls nämlich das Kernel-Log von SIGABRTs berichtet und überall Core-Dumps rumliegen, dann kann man sich langes rumschrauben am Logging sparen und stattdessen gleich die fehlerhafte PHP-Extension suchen und neuinstallieren.
Recently I replaced my office’s filtering network bridge which still ran on an old FreeBSD 4.11 box for the last eight years or so. The new system is based on a Soekris 5501, and because it took some time to choose the right software I decided to publish my notes on the tested BSD firewall products.
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Recently I had to work with SQL dumps to recover a database server and to update a MySQL installation. Because complete SQL dumps are too big to handle them with diff and vi (with enough memory vim actually works on large files, but it is really slow) I needed more traditional tools to compare them and to extract only the parts I needed.
Names and numbers are important but invaluable resources in IT (e.g. URIs, IPs, e-mail adresses). Their consideration nicely distinguishes techies (for lack of a better word; everyone with certain technological experience and proficiency) from non-techies (e.g. management :->).
Non-techies see these resources as abundant and dirt-cheap because they do not cost any money. – Whereas techies regard them are scarce and expensive because no amount of money can completely revert a bad allocation.
Just to preserve it, here’s a useful shell command line to print a histogram of frequent log events:
grep -h 'expr' files | cut -d ' ' -f 1,2 | uniq -c | awk '{step=5; bar = ""; for(i = $1; i>=1; i = i-step) bar = bar "#"; printf $2, $3, bar; }'
Given a multiuser webserver with PHP and error logging to syslog. Problem: how do you correlate error messages with users? This patch lets PHP call openlog() with a configurable program name. Read the rest of this entry »
