The Advisory Boar

By Abhijit Menon-Sen <>

SATA errors with flaky power cable

Just for the record—a bad SATA power cable is capable of provoking intermittent errors such as the following:

ata4: exception Emask 0x10 SAct 0x0 SErr 0x4050002 action 0xe frozen
ata4: irq_stat 0x00400040, connection status changed
ata4: SError: { RecovComm PHYRdyChg CommWake DevExch }
ata4: hard resetting link
ata4: SATA link down (SStatus 0 SControl 300)
ata4: EH complete

Two chassis fans and a disk were sharing a single 4-pin molex connector from the power supply. The problem was that the pin sockets on the fan connectors were loose and misaligned, and one of them became dislodged when the disk connector was plugged in. Pushing the pins into place and reattaching the connectors solved the problem.

Too many filesystems

While trying to explain something about filesystems the other day, I realised that there are too many different (but related) things that can be reasonably described by that term.

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It's a toroid, not a primate!

My server acts as a secondary nameserver for, in which zone it is named I set that up long ago for a friend, and forgot all about it. Until now.

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Delivering mail to Hotmail

I just helped a friend move mail service for a few domains from his old server to a new one running Postfix, Archiveopteryx, and Roundcube. The move went well, but for one thing: mail sent through the new server to Hotmail was accepted, but never delivered to the recipient's inbox, no matter how permissive the anti spam settings. (Mail sent to GMail and Yahoo worked fine.)

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libjpeg-turbo is very fast

I recently discovered libjpeg-turbo, a drop-in replacement for the venerable that uses SIMD instructions to achieve 2–4x the performance of the old library.

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Git disaster recovery

I typed git commit and git push, and a few seconds later, the mains power died.

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Nokia 7210 as a GPRS modem under Linux

Here's a brief report of the Nokia 7210 Supernova, which does GPRS and Bluetooth well enough to be used as a modem with our Lenovo S10 on a trip out of town.

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Ubuntu 9.10 works on the Lenovo Ideapad S10

I installed Ubuntu 9.10 on our Lenovo Ideapad S10 (which was running 8.10), and I also got to install it on a friend's new S10-2. There's little to report in either case.

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An ezmlm-landmine for the unwary sysadmin

I encountered a nasty surprise in the form of a carelessly-written shell script disguised as an ezmlm command.

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Installing CentOS 5.3 remotely

I was able to install CentOS 5.3 remotely using a VNC client.

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