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Am 29.11.2011 05:10, schrieb Michael Mol: |
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> I've got four 750GB drives in addition to the installed system drive. |
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> |
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> I'd like to aggregate them and split them into a few volumes. My first |
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> inclination would be to raid them and drop lvm on top. I know lvm well |
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> enough, but I don't remember md that well. |
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> |
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> Since I don't recall md well, and this isn't urgent, I figure I can look |
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> at the options. |
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> |
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> The obvious ones appear tobe mdraid, dmraid and btrfs. I'm not sure I'm |
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> interested in btrfs until it's got a fsck that will repair errors, but |
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> I'm looking forward to it once it's ready. |
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> |
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> Any options I missed? What are the advantages and disadvantages? |
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> |
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> ZZ |
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> |
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|
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Sounds good so far. Of course, you only need mdraid OR dmraid (md |
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recommended). What kind of RAID level do you want to use, 10 or 5? You |
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can also split it: Use a smaller RAID 10 for performance-critical |
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partitions like /usr and the more space-efficient RAID 5 for bulk like |
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videos. You can handle this with one LVM volume group consisting of two |
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physical volumes. Then you can decide on a per-logical-volume basis |
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where it should allocate space and also migrate LVs between the two PVs. |
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Another thing you can think of is whether you want encryption. I've done |
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this for my laptop. The usual setup would by md->lvm->crypt. I've done |
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it crypt->lvm (an LVM physical volume on top of an encrypted partition). |
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This way, I only need to enter the password once. You can enforce a |
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specific order between lvm, md and dmcrypt by putting stuff like this in |
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/etc/rc.conf: |
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rc_dmcrypt_before="lvm" |
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rc_dmcrypt_after="udev" |
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|
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Regards, |
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Florian Philipp |
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