Category: linux

mdadm woes

After migrating a software RAID 5 to Ubuntu LTS 12.04, the system wouldn't come up again after rebooting. I believe Chris Siebenmann to splendidly have analysed [1] the problem: a race condition with udev losing the race. His solution is to: Change /usr/share/initramfs-tools/scripts/mdadm-functionsas follows: degraded_arrays() { + udevadm settle mdadm --misc --scan --detail --test >/dev/null … Continue reading mdadm woes

Reducing HP 4720s power consumption under Ubuntu Linux 11.10

Mainly annoyed by the loud fan I looked into ways of reducing power consumption of the HP Probook 4720s and came up with this script:#!/bin/sh -e# Increase filesystem write cache timeoutecho 1500 > /proc/sys/vm/dirty_writeback_centisecs  # Enable power management on all PCI devicesfind /sys/devices/pci* -path "*power/control" -exec bash -c "echo auto > '{}'" \;# Enable power … Continue reading Reducing HP 4720s power consumption under Ubuntu Linux 11.10

Enabling the powerbutton in Ubuntu Server 10.04 on an AMD box

While shutdown –h does the trick of shutting down a server just fine, occasionally I’d prefer the haptic version. While I’ve never had problems getting the powerbutton to work with Ubuntu desktop versions, it didn’t work out of the box on my AMD Athlon XP. Fortunately the solution seems to be quite simple: sudo apt-get … Continue reading Enabling the powerbutton in Ubuntu Server 10.04 on an AMD box