Karim Vaes

It’s always good to do a regular rootkitcheckup on your system. A nice tool for doing so is rkhunter.

1.1) What is Rootkit Hunter?
Rootkit Hunter (RKH) is an easy-to-use tool which checks
computers running UNIX (clones) for the presence of rootkits
and other unwanted tools.
1.2) What are rootkits?
Most times they are self-hiding toolkits used by blackhats,
crackers and scriptkiddies, to avoid the eye of the sysadmin.

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A while back a wrote a small note about linux for embedded devices. Yesterday I put that to the test by installing OpenWRT on my Linksys WRTG (v2.2).

The installation was as smooth as ice: No problems at all! I first installed the latest stable. This was simply done by logging into the existing webinterface of my Linksys WRTG, and doing a firmware upgrade with the specific image for my linksys.

A note here: Read the common mistakes, like for instance this important one.

“You need to convert the bin (eg. openwrt-wrt54g-squashfs.bin) file to a trx file before reflashing” WRONG!!!

The openwrt-brcm-squashfs.trx is a generic trx file that will work on any supported broadcom platform. The openwrt-wrt54g-squashfs.bin is just “bin header + openwrt-brcm-squashfs.trx’, the bin header just contains the firmware version number and what models the firmware can be loaded on; the bin header is only used for verification before writing the trx data to the flash. The mtd utility writes the given file to flash without verifying it; use one of the openwrt-brcm-squashfs.trx when using mtd. Converting the openwrt-wrt54g-squashfs.bin file back to a trx is just plain ignorant.

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If you want a decent explanation about the internals of the linux memory usage, check the following article:
here

What I hated was that when I opened up some new terminal windows that it left some space unused between the windows. Okay, there are some tiling windows managers, yet I still like the whole desktop feeling xfce gives me (without the resource bloat Gnome & Kde).

So I checked what size my terminal was when I had four of them open, and I set that value as their “startup size”. How can you do this?

xfce4-terminal –geometry 110×35

Original information found here.

Read up on this article.

Learn more about direct I/O, concurrent I/O, asynchronous I/O, and best practices for each method of I/O implementation. This three-part series on the AIX® disk and I/O subsystem focuses on the challenges of optimizing disk I/O performance. While disk tuning is arguably less exciting than CPU or memory tuning, it is a crucial component in optimizing server performance. In fact, partly because disk I/O is your weakest subsystem link, you can do more to improve disk I/O performance than on any other subsystem.

Credits go to “Ken Milberg” on writing the article. I enjoyed reading it, as it was very interesting.