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On Tuesday 19 July 2011 16:36:20 you wrote: |
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> On Tuesday 19 July 2011 09:06:05 Michael Orlitzky wrote: |
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> > On 07/18/2011 11:08 PM, Jeff Cranmer wrote: |
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> > > Pardon my additional questions before taking the plunge here. |
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> > > |
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> > > So, given that I have three devices, /dev/sda, /dev/sdb and |
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> > > /dev/sdc, if I run the command mdadm --assemble --scan, would this |
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> > > find all the components and create a /dev/md0 disk without damaging |
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> > > the contents of the original RAID array? |
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> > |
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> > If you've got the space and time, a backup can't hurt. Using --scan will |
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> > make it check the config file, but right now, there's probably nothing |
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> > |
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> > useful in it. This looks like what you want to do to me: |
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> > If the --scan option is not given, then only devices and identities |
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> > listed on the command line are considered. |
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> > |
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> > The first device will be the array device, and the remainder will be |
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> > examined when looking for components. |
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> > |
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> > but I'd figure out where that md0 is coming from (below) first. |
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> > |
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> > > The only item in /dev/mapper is th default 'control' entry. There |
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> > > is |
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> > > a /dev/md0 item already listed, but presently when I try to mount |
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> > > it, it reports that it is unable to read the superblock. Would the |
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> > > command above fix this? |
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> > |
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> > Depends. Where'd the md0 come from? You probably have something in your |
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> > logs or dmesg, unless that device was created manually on your old |
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> > system.> |
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> > > Where is the config file mentioned in your e-mail, and do I need to |
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> > > edit it first to add the three raid disks? |
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> > |
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> > It's /etc/mdadm.conf. You don't need it to create or use the array, but |
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> > you'll want to run mdadm when the machine boots and the config file |
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> > tells it what to do. Once the array is working, you can just do, |
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> > |
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> > mdadm --detail --scan >> /etc/mdadm.conf |
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> > |
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> > to populate it. I guess also check to make sure there's no default crap |
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> > in there these days. |
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> |
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> mdadm? that is for linux software raid. |
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> |
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> He wants to use nvidia fakeraid. He needs dmraid for that. |
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> |
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> Build in the dmraid support. |
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> emerge device-mapper |
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> emerge dmraid |
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> add device-mapper to boot runlevel |
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> done |
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> |
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> If I remember correctly |
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> |
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> oh yeah - nvidia fakeraid is pretty fragile. You should plan to move away |
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> from it. |
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addendum: just saw that mdadm >=3 should be able to handle fake raid. |
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My bad. |
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-- |
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#163933 |
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