Recently I discovered gnump3d. It supports downsampling, which is a feature I especially need. However, the example reencoding command for handling MP3s doesn’t seem to work. Instead, I am using a different variant.

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Since I deployed DokuWiki last fall, I’ve found it to be an excellent tool for managing documentation. It enhances the quality of the final documentation product whilest not getting in the way of writing it. I rather enjoy it.

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I so rarely use 3D on my Debian GNU/Linux desktop, I didn’t bother to verify it was working when I upgraded to Etch. Actually, it’s probably been busted since I moved to the unofficial Xorg in Sarge Backports in December. The Debian WiKi has the solution, essentially.

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Should you need to download packages from a unofficial repository, you need not disable gpg signature verification. Instead, you can import the key used to sign the packages into your local keyring.

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Because I enjoy deep hurting, I thought it would be fun to reverse proxy Apache 1.3 using Apache 2.2 with Wordpress 2.1 hosted under the former. With Wordpress 2.1, the rewrite rules generated for the date schema are considerably shorter, but still require a few minor changes to proxy happily.

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My relationship with dspam, a bayesian classifier based spam solution, has been unwavering since I first installed it in 2005. I previously used SpamAssassin. While SpamAssassin offers a wide variety of tests involving potentially dozens of sources including rulesets, DNS blacklists, URI blacklists, checksum databases, and bayesian classifying, I found its false negative rate unacceptable and resource overhead excessive.

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Presently, I now need to support a Ubuntu x86_64 environment. Several internal Debian packages I have must now be deployed onto the 64-bit, split lib Ubuntu environment. Sadly, I have no 64-bit build host presently. Fortunately, QEMU provides a solution.

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Munin has support for sending mails when specified warning and critical thresholds are exceeded. If you aren’t already running a notification system, such as Nagios, Munin’s notification works splendidly. A few changes to munin.conf are all that’s needed.

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I have written a new guide, focusing on backporting Debian GNU/Linux packages to earlier releases.

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Recently, I have found myself with two independent internet feeds. The nice side effect of having two feeds is you can configure multipath routing, load balancing, failover, and dead gateway detection. However, for a individual setup there isn’t much value in configuring all that is necessary for the latter items. Nevertheless, configuring multipath routing can be quite valuable, allowing select traffic to travel over an intentionally underutilized link for reduced latency, increased bandwidth, or what have you.

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A couple of years ago, I was singing the praises of milter-greylist. While greylisting is still effective, in the past year I’ve noticed an increase in the number of spammers, especially this year, that utilize more RFC compliant spamming tools that resend on temporary failure. To combat that, I have recently started using milter-regex to reject on, among other things, invalid HELO strings.

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After experiencing a variety of hardware failures recently, I finally completed my migration to syslog-ng with a central loghost paired with hourly log reporting using a wrapper script around logcheck. Once properly tuned, an ongoing process, mails generated and often of some interest.

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One of the most painful deployment issues for Linux Traffic Control on a commodity ADSL link is the variable overhead relative to IP for each packet you transmit, as the underlying transport is actually ATM. Each ATM cell is a 53 byte fixed length with a capacity for 48 bytes of actual data. Unfortunately, much of that 48 bytes is consumed by overhead from PPP, LLC, AAL5, and so forth. This is especially bad for small packets, like TCP ACK packets which are only 40 bytes over Ethernet, but with overhead across an ATM network actually require two full ATM cells to transmit in most cases.

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First, boot with a kernel commandline of ydebug to attempt a recovery. In the following example, the device name for a md based RAID 1 device has shifted, resulting in a boot failure. When the underlying block device name changes, a Yaird image will fail as it hardcodes device names.

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If you’ve been trying to run VMWare v4.5 on the latest Linux release candidate kernels, you may be having trouble compiling it. Fortunately, a few quick fixes and you should be able to compile again.

Read the rest of “Running VMWare Workstation v4.5.2 on Linux 2.6.16″ »