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Edward Middleton posted <4368286D.90909@××××××××××××.jp>, excerpted below, |
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on Wed, 02 Nov 2005 11:46:05 +0900: |
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|
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>>It appears most aren't running into this bug, yet the number of bugs |
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>>suggests there's a fair number of users. |
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> This bug will only effect users of root on lvm2 users |
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|
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BTW, I'm not fully up and working yet, but I've decided to put root |
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directly on (a partitioned) raid6, so it can be directly auto-assembled by |
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the kernel and I won't have to use an initrd/initramfs, as (I believe??) I |
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would if root was on LVM2. (The software raid howto is outdated when it |
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says Linux raid can't be partitioned. The 2.6 kernel handles that just |
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fine, but with different device numbers than the traditional |
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non-partitionable raid.) |
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|
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I got 4-300 gig Seagates -- 1.2 terabyte of raw disk space (plus my |
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existing PATA drive space). One of the reasons I'm not up and running yet |
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is that I double-checked the raw drives by running badblocks -w on each |
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entire drive. That's four patterns, written out one at a time to four |
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drives, 300 gig each, then read back in and verified. 4x4x300 gig = 4.8 |
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terabytes written, 4.8 terabytes read. That took me a couple days! =8^) |
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Fortunately, I didn't feel it much at all, save for the wait, because that |
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was traffic on drives I'm not yet using in production, and while it did |
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run 1 CPU to 100% for the entire period, that was mostly I/O wait, and my |
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other CPU kept up with the normal desktop stuff just fine. Anyway... it |
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was waiting for that, that I realized just how much drive space I now |
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have! =8^) |
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|
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I have the raid6 partitioned three ways, my traditional root and |
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backup-root-snapshot as two partitions with the third being the big one -- |
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to hold the rest of my raid6 volumes in LVM, again, for the additional |
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flexibility. There's enough space on the LVM-on-raid6 partition to keep a |
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working and a snapshot copy of everything there, too, guarding against |
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fat-fingering as well as hard drive failure. (A second copy of everything |
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means very little risk playing with reiser4 or the like, as well! =8^) |
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|
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Right now, I have three raids set up (altho I haven't installed |
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filesystems on them yet), a small raid0 (mirrored) for booting, the |
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majority of the space as the three-way-partitioned raid6 mentioned above, |
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and a raid0 (striped for speed, non-redundant) for semi-volatile storage, |
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the portage tree as it can easily be resynced for recovery, /tmp, etc (no, |
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not /etc! <g>). However, after reading up on LVM and realizing it had |
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built-in striping capabilities, I may kill the raid0 and simply use |
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striped LVM directly on the physical volume partitions underneath. |
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|
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Anyway... it was quite cool to realize the 2.6 kernel handles partitioned |
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raid, now, and with direct boot-time kernel raid assembly, I could run |
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root on raid6 without an initrd/initramfs! As I was dreading the |
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complexity of an initrd solution, I grabbed the opportunity to avoid it |
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and still have a raid-backed root, when I saw it! So, no root on LVM |
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here! |
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|
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-- |
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Duncan - List replies preferred. No HTML msgs. |
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"Every nonfree program has a lord, a master -- |
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and if you use the program, he is your master." Richard Stallman in |
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http://www.linuxdevcenter.com/pub/a/linux/2004/12/22/rms_interview.html |
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|
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|
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-- |
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