{"id":17,"date":"2010-04-28T15:59:14","date_gmt":"2010-04-28T22:59:14","guid":{"rendered":"http:\/\/10.43.101.63:24469\/?p=17"},"modified":"2017-02-21T01:02:10","modified_gmt":"2017-02-21T09:02:10","slug":"recovering-from-a-multiple-disk-failure-with-linux-software-raid5","status":"publish","type":"post","link":"https:\/\/aarontc.com\/archive\/2010\/04\/recovering-from-a-multiple-disk-failure-with-linux-software-raid5\/","title":{"rendered":"Recovering from a multiple-disk failure with Linux software RAID5"},"content":{"rendered":"

The scenario is this: I have a system with several external USB hard drives that are part of a RAID5 array. (It’s a work in progress, I’m simply out of SATA controllers right now.) The problem is that sometimes (about once per month) two or more of the drives will have USB bus errors simultaneously and go offline. This causes the RAID array to stop in its tracks.<\/p>\n

The solution is simple, but it’s taken a bit of testing and research to make sure it works. So here goes:
\nmdadm --assemble --force \/dev\/md1<\/code>
\nThis causes mdadm to update the event count on the drives which simultaneously disconnected to match the drives that were fine all along. After a quick resync, everything is happy again.<\/p>\n

Here’s where I found this tidbit: http:\/\/www.linux.org\/docs\/ldp\/howto\/Software-RAID-HOWTO-8.html<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

The scenario is this: I have a system with several external USB hard drives that are part of a RAID5 array. (It’s a work in progress, I’m simply out of SATA controllers right now.) The problem is that sometimes (about once per month) two or more of the drives will have USB bus errors simultaneously […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_newsletter_tier_id":0,"footnotes":"","jetpack_publicize_message":"","jetpack_is_tweetstorm":false,"jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false}}},"categories":[5,4],"tags":[56,11,12,13],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p6PV8H-h","jetpack-related-posts":[{"id":335,"url":"https:\/\/aarontc.com\/archive\/2012\/04\/checking-software-raid-arrays-under-linux\/","url_meta":{"origin":17,"position":0},"title":"Checking software RAID arrays under Linux","author":"Aaron","date":"April 30, 2012","format":false,"excerpt":"Mostly as a reminder to myself... it's important to have a cron job that verifies your RAID array integrity on a regular basis. (Once a week is what most hardware RAID controllers seem to use.) This is accomplished with a command such as: echo check > \/sys\/block\/md0\/md\/sync_action Replace md0 with\u2026","rel":"","context":"In "Linux"","block_context":{"text":"Linux","link":"https:\/\/aarontc.com\/archive\/category\/linux\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":315,"url":"https:\/\/aarontc.com\/archive\/2011\/12\/linux-is-not-windows\/","url_meta":{"origin":17,"position":1},"title":"Linux is Not Windows","author":"Aaron","date":"December 18, 2011","format":false,"excerpt":"Yesterday, Mark pointed me at the following article, which I feel is quite relevant to most Linux versus Windows debates that go on these days. In particular, the analogies of cars versus motorbikes, and paid support (no community) versus free support (community), seem to do a fantastic job of explaining\u2026","rel":"","context":"In "Linux"","block_context":{"text":"Linux","link":"https:\/\/aarontc.com\/archive\/category\/linux\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":233,"url":"https:\/\/aarontc.com\/archive\/2010\/09\/mark-shuttleworth-%c2%bb-blog-archive-%c2%bb-reflections-on-ubuntu-canonical-and-the-march-to-free-software-adoption\/","url_meta":{"origin":17,"position":2},"title":"Mark Shuttleworth \u00bb Blog Archive \u00bb Reflections on Ubuntu, Canonical and the march to free software adoption","author":"Aaron","date":"September 15, 2010","format":false,"excerpt":"Interesting commentary on recent criticism that Ubuntu has received for not contributing to the Linux kernel: Mark Shuttleworth \u00bb Blog Archive \u00bb Reflections on Ubuntu, Canonical and the march to free software adoption.","rel":"","context":"In "Linux"","block_context":{"text":"Linux","link":"https:\/\/aarontc.com\/archive\/category\/linux\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":367,"url":"https:\/\/aarontc.com\/archive\/2013\/04\/lossless-hd-audio-over-hdmi-with-pulseaudio-under-linux\/","url_meta":{"origin":17,"position":3},"title":"Lossless HD Audio over HDMI with PulseAudio under Linux","author":"Aaron","date":"April 13, 2013","format":false,"excerpt":"Today I finally managed to get lossless HD audio working from my Linux media PC over HDMI! I'll probably update this post as time goes, but for now it's a quick recipe of what I did: Configure a PulseAudio ALSA sink to use the HDMI output Video cards present HDMI\u2026","rel":"","context":"In "Linux"","block_context":{"text":"Linux","link":"https:\/\/aarontc.com\/archive\/category\/linux\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":329,"url":"https:\/\/aarontc.com\/archive\/2012\/03\/cool-open-source-games\/","url_meta":{"origin":17,"position":4},"title":"Cool Open Source Games","author":"Aaron","date":"March 15, 2012","format":false,"excerpt":"I was made aware of this article by Chris Haverkate, and I think it deems sharing: Cool Open Source Games You Should Contribute To","rel":"","context":"In "Linux"","block_context":{"text":"Linux","link":"https:\/\/aarontc.com\/archive\/category\/linux\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":292,"url":"https:\/\/aarontc.com\/archive\/2011\/04\/automatically-keywording-unmasking-gentoo-packages\/","url_meta":{"origin":17,"position":5},"title":"Automatically Keywording\/Unmasking Gentoo Packages","author":"Aaron","date":"April 23, 2011","format":false,"excerpt":"Today I wanted to try a masked version of KDE on my laptop. As KDE is a very large set of packages, I was not looking forward to manually keywording every required package. Luckily, someone else has solved this problem. A quick Google search led me to autounmask which didn't\u2026","rel":"","context":"In "Gentoo"","block_context":{"text":"Gentoo","link":"https:\/\/aarontc.com\/archive\/category\/linux\/gentoo\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"_links":{"self":[{"href":"https:\/\/aarontc.com\/wp-json\/wp\/v2\/posts\/17"}],"collection":[{"href":"https:\/\/aarontc.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/aarontc.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/aarontc.com\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/aarontc.com\/wp-json\/wp\/v2\/comments?post=17"}],"version-history":[{"count":8,"href":"https:\/\/aarontc.com\/wp-json\/wp\/v2\/posts\/17\/revisions"}],"predecessor-version":[{"id":614,"href":"https:\/\/aarontc.com\/wp-json\/wp\/v2\/posts\/17\/revisions\/614"}],"wp:attachment":[{"href":"https:\/\/aarontc.com\/wp-json\/wp\/v2\/media?parent=17"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/aarontc.com\/wp-json\/wp\/v2\/categories?post=17"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/aarontc.com\/wp-json\/wp\/v2\/tags?post=17"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}