http://bertrand.gotpike.org//space/start/2006-07-06/1After a powerfailure on my main file server, reiserfsck said some errors was found on a reiserfs partition, and <b class="bold">reiserfsck --rebuild-tree</b> was required.<p class="paragraph"/> Off course, RAID 1 doesn't help in this case.<p class="paragraph"/> The reiserfsck man page says you'd better backup your data before proceeding with <b class="bold">--rebuild-tree</b>.<p class="paragraph"/> __Believe them__.<p class="paragraph"/> Following this advice, i hopefully made a last backup before proceeding. The reiserfs partition was perfectly readable, except some files.<p class="paragraph"/> Crawling the web, i learned on multiple sites that until <b class="bold">reiserfsck --rebuild-tree</b> hasn't finished it's job, the partition was unusable at all.<p class="paragraph"/> This operation really takes a long time. Don't estimate the time remaining on the number on remaining blocks and the blocks/seconds. Mine was stuck for many hours on pass #2, eating as much as CPU as possible.<p class="paragraph"/> Waiting for more than 12 hours for repairing a 200GB partition was fruitless: it ended up saying there were not enough space left on the drive. Not only the drive had a powerfailure while writing data, but some people here were uploading lots of data and there were very little space left (around 5MB). That's something like Murphy's law.<p class="paragraph"/> The backup was put in place, i strongly believed the original reiserfs partition were lost forever. I better understand now the amount of blocks reserved for root on ext2/ext3 filesystems. I think i'll have a look if this kind of option is available on reiser, too.<p class="paragraph"/> I relaunched the check, mostly for educational purpose. Noone were complaining about lack of data nor data corruption on the backup.<p class="paragraph"/> It runned all the night, and on the next morning the drive was <b class="bold">totally fixed</b>.<p class="paragraph"/> OK, <b class="bold">reiserfsck --rebuild-tree</b> did it's job. Thanx to all reiserfs crew. It didn't ate data, but it took almost 24 hours to do that, an amount of time i couldn't make my users wait for.<p class="paragraph"/> I discovered i'm now too old to live with the fsck adrenalin :) I hereby promise to make stronger backups now.<p class="paragraph"/> Better spend some minutes a day backuping and making sure it's backuped than loose many hours of your life and hours/weeks/month/years of others people work on a power/hard drive failure. Fins 0.9.7http://blogs.law.harvard.edu/tech/rss