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On Tuesday 11 December 2012 05:57 PM, Alan McKinnon wrote: |
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> On Tue, 11 Dec 2012 12:08:12 +0000 |
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> Neil Bothwick <neil@××××××××××.uk> wrote: |
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> |
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>> On Tue, 11 Dec 2012 12:48:13 +0100, J. Roeleveld wrote: |
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>> |
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>>>> I'm using metadata version 1.2 for the raid0 array and the type is |
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>>>> kernel based autodetect. |
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>>> |
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>>> Ouch, auto-detect does not work with metadata 1.2. |
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>>> Please read the man-page section: |
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>>> |
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>>> Please rebuild the raid-device using v0.90 metadata and try again. |
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>> |
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>> I don't understand why your using RAID at all. LVM on top of RAID0 |
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>> makes no sense to me when you can simply make each device a PV and |
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>> add it to the VG. That's more flexible and easier to repair. |
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>> |
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>> |
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> |
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> Some folks like to do the striping in RAID, it's more controllable. 1st |
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> block on this disk, 2nd block on that disk, 3rd block on first disk |
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> again... |
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> |
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> Pooling LVM PVs into a VG is a huge gigantic basket of stuff where you |
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> don't really get to control very much - LVM sticks data wherever it |
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> wants to and you do little more than give some gentle hints (which |
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> I strongly suspect are mostly ignored) |
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> |
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> But yes, in the usual case RAID-0 on LVM doesn't make much sense for |
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> most folks. |
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> |
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> Personally, I prefer ZFS. This whole huge list of shit just goes away: |
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> |
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> disk partitions |
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> partition types |
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> disk labels |
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> worrying about if my block size is right |
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> worrying if my boundaries are correct |
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> PVs as different from VGs and LVs |
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> VGs as different from PVs and LVs |
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> LVs as different from PVs and VGs |
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> lvextend && growfs to make stuff bigger |
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> umount && shrinkfs && lvreduce && growfs && mount to make stuff smaller |
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> |
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> I can now take a much simpler view of things: |
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> |
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> "I have these disks, use 'em. When I've figured out the actual quotas |
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> and sizes I need, I'll let you know. Meanwhile just get on with it and |
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> store my stuff in some reasonable fashion, 'mkay? kthankxbye! I have |
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> real work to do." |
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> |
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> :-) |
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> |
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> |
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|
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Exactly the reason why I wanted RAID0 and LVM in combination: more IOPS. |
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ZFS looks very interesting, how stable is it? |
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|
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-- |
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Nilesh Govindarajan |
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http://nileshgr.com |
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