Tag: 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 →

Automatically starting an SSH tunnel in Ubuntu

As I am a frequent guest in public WLANs I spent some time looking into ways to connect safely to both the corporate network and the rest of the internet while enjoying the amenities of a cafés' or hotel's wifi. Because of its simplicity and universal availability I like SSH tunnels which are easily set … Continue reading Automatically starting an SSH tunnel in Ubuntu →

Reducing power consumption on the HP Probook 4720s and Ubuntu 12.04

As said earlier, Ubuntu 12.04 does a good job with power management on the 4720s. With some manual settings power consumption can be further decreases, albeit not much this time. I wrote this script which takes a parameter: on: enable power management settings off: disable power management settings extra: on + enable extensive power management … Continue reading Reducing power consumption on the HP Probook 4720s and Ubuntu 12.04 →