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* Rich Freeman <rich0@g.o> [150528 08:45]: |
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> On Wed, May 27, 2015 at 8:01 PM, Peter Humphrey <peter@××××××××××××.uk> wrote: |
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[..SNIP..] |
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> UUIDs are often preferable in these kinds of configurations, because |
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> you're less likely to run into duplicate identifiers, they don't |
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> change, and so on. If I mount root=UUID=foo, then my initramfs will |
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> try really hard to find that partition and mount it. If I mount |
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> root=label=foo then it will still try hard, but if for some reason I |
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> have more than one device with that label I could end up booting from |
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> the wrong one. If I mount root=/dev/sda1 then my boot may fail if I |
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> add a new drive, if the kernel behavior changes, if the udev behavior |
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> changes, and so on. |
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> |
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> I don't believe either the kernel or udev makes promises about device |
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> names being stable. It often works out this way, but it isn't ideal |
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> to depend on this. |
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> |
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> -- |
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> Rich |
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It's worse than just getting the wrong filesystem mounted if the wrong |
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filesystem gets mounted as /tmp. |
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OpenRC's bootmisc will wipe the /tmp directory at boot (and likely |
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systemd as well, but I haven't checked.) |
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This means if disk device names get shifted and something other than the |
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proper /tmp device gets mounted as /tmp then it's "restore-from-backups" |
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time. |
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This happened to me and wiped /home (the /dev/md* devices got renumbered |
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once.) |
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So I've switched to UUID mounts so that problem doesn't happen in the |
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future. |
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It's really unpleasant if that happens. |
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Todd |
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