2012-08-21 These days, I have upgraded two Debian machines I maintain from oldstable to stable. Theses systems are not my own ones, I only maintain them. Usually I'm a bit behind the schedule because I'm not keen to have the modern stuff like grub2, dependency based boot system, and UUIDs. But when I need archive.debian.org in the sources.list then I know I should upgrade though. The up- grades went mostly well, only small adjustments were needed: Delete xorg.conf on one machine; remove /etc/default/keyboard op- tions on the other. About two years ago Georg had told me how he had used ddrescue and how the tool worked. I had listened well because I thought I could need this somewhen. This somewhen had been yesterday. I had a movie on two CDs where the second disk threw an I/O error at 50%. The disk looked fine so I wondered. The error remained after careful cleaning. It also remained after heavy cleaning. This was the time for the ddrescue to copy the file skipping the unreadable parts. Eight read errors prevented 384kb from being read. (I only did a single read attempt because I assumed the read errors to be permanent on the disk.) The movie played fine in mplayer, only one time minor irritations (artefacts) were in the picture for about one second. For video data, a few broken frames really aren't too bad. I combined the two movie parts with mencoder to a single file: mencoder -ovc copy -oac copy *.avi -o merged.avi And burned it on DVD: growisofs -Z /dev/hda -R -J merged.avi The old CDs can be trashed now. I should do this for other CDs I have as well. Optical disks should be copied to new media every few years. It's time to do this soon. http://marmaro.de/lue/ markus schnalke