Now I know nobody uses this kind of raid technology anymore, but it was one of the cool things I learned from my mentor at the time, when I first started my career centuries ago. I happen to find this in my archives and thought I would write up to share.<\/p>\n
There is another way to do this as using mdadm & sfdisk. When I find time I will share how to do that as well.<\/em> <\/strong><\/p>\n 1.<\/span>First thing you want to do is check to see drive has fallen out of the raid by running the following command below<\/p>\n<\/div>\n md<\/span>2 :<\/span> active raid1 hda3[0] hdc3[1]<\/span><\/p>\n 524096 blocks [2\/2] [UU]<\/span><\/p>\n md<\/span>1 :<\/span> active raid1 hda2[0] hdc2[1]<\/span><\/p>\n 524096 blocks [2\/2] [UU]<\/span><\/p>\n md<\/span>0 :<\/span> active raid1 hda1[0]<\/span><\/p>\n 78994304 blocks [2\/1] [U_]<\/span> *You notice this one is showing a drive has fallen out*<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n Note: <\/em><\/strong>If you see this, take notice to the one with <\/em>[U_] <\/em><\/span>this line means that the drive has fallen out of the raid. <\/em><\/strong><\/p>\n 1. To enter it back in run the lines below, based on the drive assignments in the above paritions that are good.<\/p>\n How to rebuild a failed drive in software if you replace<\/span>d<\/span> the drive<\/span>:<\/span><\/strong><\/p>\n \u2022<\/span> <\/span>cat \/proc\/mdstat<\/em><\/p>\n md2 : active raid1 hda3[0] hdc3[1]<\/span> 2. recreate the paritions on the new drive by doing the following, using the same mirror drive designations from \/proc\/mdstat.<\/p>\n 3. Next check the partition by running<\/p>\n Disk \/dev\/hdc: 81.9 GB, 81964302336 bytes<\/p>\n 16 heads, 63 sectors\/track, 158816 cylinders<\/p>\n Units = cylinders of 1008 * 512 = 516096 bytes<\/p>\n .<\/span><\/span><\/p>\n Device Boot Start End Blocks Id System<\/p>\n \/dev\/hdc1 * 1 156735 78994408+ fd Linux raid autodetect<\/p>\n \/dev\/hdc2 156736 157775 524160 fd Linux raid autodetect<\/p>\n \/dev\/hdc3 157776 158815 524160 fd Linux raid autodetect<\/p>\n .<\/span><\/span><\/p>\n Disk \/dev\/hda: 81.9 GB, 81964302336 bytes<\/p>\n 16 heads, 63 sectors\/track, 158816 cylinders<\/p>\n Units = cylinders of 1008 * 512 = 516096 bytes<\/p>\n .<\/span><\/span><\/p>\n Device Boot Start End Blocks Id System<\/p>\n \/dev\/hda1 * 1 156735 78994408+ fd Linux raid autodetect<\/p>\n \/dev\/hda2 156736 157775 524160 fd Linux raid autodetect<\/p>\n \/dev\/hda3 157776 158815 524160 fd Linux raid autodetect<\/p>\n ———————————————————————<\/p>\n Filesystem Size Used Avail Use% Mounted on<\/p>\n \/dev\/md0 75G 11G 60G 16% \/<\/p>\n none 251M 0 251M 0% \/dev\/shm<\/p>\n \/dev\/md1 496M 8.1M 463M 2% \/tmp<\/p>\n 4. Next you want it rebuild the partitions on the new drive so run the following, you will need to update your drive designation according to your drive assignment.<\/p>\n .<\/span><\/span><\/p>\n Note: the primary partition should match the new drive designation ‘dev\/md0 \/dev\/hdc1’.<\/em><\/strong><\/p>\n","protected":false},"excerpt":{"rendered":" Now I know nobody uses this kind of raid technology anymore, but it was one of the cool things I learned from my mentor at the time, when I first started my career centuries ago. I happen to find this in my archives and thought I would write up to share. There is another way to do this as usingRead More …<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[138,127],"tags":[],"class_list":["post-1090","post","type-post","status-publish","format-standard","hentry","category-linux","category-linux-software-raid-stuff"],"_links":{"self":[{"href":"https:\/\/nicktailor.com\/tech-blog\/wp-json\/wp\/v2\/posts\/1090","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nicktailor.com\/tech-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/nicktailor.com\/tech-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/nicktailor.com\/tech-blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/nicktailor.com\/tech-blog\/wp-json\/wp\/v2\/comments?post=1090"}],"version-history":[{"count":14,"href":"https:\/\/nicktailor.com\/tech-blog\/wp-json\/wp\/v2\/posts\/1090\/revisions"}],"predecessor-version":[{"id":1593,"href":"https:\/\/nicktailor.com\/tech-blog\/wp-json\/wp\/v2\/posts\/1090\/revisions\/1593"}],"wp:attachment":[{"href":"https:\/\/nicktailor.com\/tech-blog\/wp-json\/wp\/v2\/media?parent=1090"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nicktailor.com\/tech-blog\/wp-json\/wp\/v2\/categories?post=1090"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nicktailor.com\/tech-blog\/wp-json\/wp\/v2\/tags?post=1090"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n 524096 blocks [2\/2] [UU]<\/span>
\nmd1 : active raid1 hda2[0] hdc2[1]<\/span>
\n 524096 blocks [2\/2] [UU]<\/span>
\nmd0 : active raid1 hda1[0]<\/span>
\n 78994304 blocks [2\/1] [U_]<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n