This is just a quick notice that during the last five days there was a problem with the website feeds. The web server returned a 500 Internal Server Error to almost all requests for /feed/ URLs. Also, there was a big increase of the server’s CPU load behind the scenes, which was caused by php-cgi processes. It turned out that a custom plugin (unpublished) I had written for WordPress in the past was the cause of all the trouble, but, before coming to that conclusion, the fact that the problems had started without me doing anything on the blog during the last weeks together with a series of other random observations led me do a thorough examination of the whole server just in case.
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I can still recall the excitement of the first time I tried to access and administer a remote system using SSH. Accessing my shell at a remote machine securely, being able to do local and remote port forwarding in order to access remote services through encrypted tunnels, X forwarding, secure file transfers using scp or sftp, authentication using public key infrastructure are just a few of the features that justify the excitement of the first time. The only Secure Shell server implementation I had used all that time was the OpenSSH server. Although this is an open-source project, the fact that it is written in C makes it extremely difficult for me to have fun with it by making any modifications in order to implement even simple things like command filtering. This is because I have never programmed in C and do not intend to learn how to do it in the foreseeable future. So what I’ve been looking for today was a server implementation of the SSH2 protocol written in Python. Unfortunately, there is no such project ready for immediate use. I had to hack my own! After several hours of trial and error, having written dozens of sample scripts for testing, I finally created a minimal project, called RapidSSH, in order to demonstrate how to create a fully functional SSH server with just a few lines of Python code by using Twisted.conch, part of the Twisted Framework. Read on…
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If you’ve tried out several wiki engines, you have probably noticed that the developers of each of them have invented their own wiki markup language. I guess no-one has a problem with that. It’s a free world after all. However, all these different versions of markup languages easily become a pain when you have to submit content to several different wiki engines. For instance, Wikipedia, various popular bug trackers, wiki engines dedicated to projects like Ubuntu are all very popular wikis, but, unfortunately, the contributor has to learn several different markup languages to be able to submit rich content to all of them.
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I still haven’t figured out whether it happened because of pure stupidity, temporary brain malfunction or low caffeine concentration in the blood, but a week ago, by mistake, I wiped the MBR of my primary desktop’s hard disk and also (because, you know, the MBR alone is never enough!) the boot sector of the first NTFS partition, where all my personal data was, while messing around with the install-mbr utility early in the morning.
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It seems there is an issue with the Spamassassin FH_DATE_PAST_20XX test. This test checks whether the email has a date in the future and, if this is the case, raises the message’s score. Apparently, this test is falsely triggered by all emails that have been sent in 2010, producing several false positives. Since, I do not have much time to investigate this issue and to follow the news, I decided to inactivate it until I am certain it has been resolved.

[Update: It has been resolved. Update you SA rules]
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I wish a happy new year to all, full of happiness, health, creativity and peace of mind.

During the last six months, running a CentOS server as a guest in Virtualbox or VMware has been as common for me as running a web browser. This is because I’ve constantly been trying to streamline the server configuration and utilize new technologies or techniques attempting to get better performance or just make it easier to maintain. The only issue I had to face during all this time was the high CPU usage on the host, which in some cases exceeded 40%, even when the guest (CentOS server) was in idle state. At first, I had thought that the host’s operating system, Windows 7 RC (Release Candidate), was somehow incompatible with Virtualbox/VMware.
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There has been much controversy lately about Sun‘s acquisition by Oracle and how it will affect the future of the widely used open-source RDBMS, MySQL.
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Mozilla has announced the general availability of version 3 of its popular open source email & newsgroup client, Thunderbird. Thunderbird has been my desktop email client of choice since its early stable releases, both in Linux and Windows. Actually, the only programs I’ve ever used for email and newsgroup management are Outlook Express, Mozilla Thunderbird and Novell/Ximian Evolution. Out of those 3, Thunderbird, although not a strong candidate when it comes to performance, ranks 1st, since it offers the best:

1. security
2. reliability
3. backwards compatibility
4. extensibility

A few years ago, I had published an approach on how to organize mailing list messages using Evolution. The same tips and tricks apply to Thunderbird, so those of you who deal with many mailing lists might find that old article interesting.

The highlights of the new release include:
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During the last weekend, I made some changes to the website’s feeds. It seems that, after 4 years of blogging, I have finally made up my mind about what is needed and what is unnecessary regarding the syndicated content on G-Loaded.
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