Linux System Admins Blog

Linux systems traditionally keep the definition of their timezone in /etc/localtime. This is a binary file with the timezone info, and if we want to change it we need to find the appropriate timezone file from /usr/share/zoneinfo and copy it over the one from /etc or just link to it. Once you change it, you [...]

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It’s a bit of a long title for a blog post but the point I want to make is that not every query optimization is aimed at making the query faster. As a case in point we have a client that has a web shop and their network traffic between the web servers and the [...]

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While investigating some ftp transfers issues we realized that there was something wrong with the logs generated by vsftpd. The timestamps reported in the vsftpd log were wrong, and the fact that they were always 5 hours behind the actual time made us think this was caused by a timezone issue. The system running this [...]

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When I started working in systems, one of my first client was a major bank.  Yes, this was back in the mainframe batch processing days.  They never did any system updates when they ran the month end, quarter end and especially year end.
I always thought that they just weren’t confident in their system folks and [...]

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The Domain Name System (DNS) is responsible for translating host names to IP addresses (and vice versa) and is critical for the normal operation of internet-connected systems. DNS cache poisoning (sometimes referred to as cache pollution) is an attack technique that allows an attacker to introduce forged DNS information into the cache of a caching [...]

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E-commercre Report; Several of the most popular online merchants have struggled to cope with the heavy holiday traffic, a survey shows.
Ok, that was NYTimes 2003 – what about now?   This season there have already been several announcements of ecommerce snafus.  Sears.com site shut down for a couple of hours and there have even been [...]

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