[gentoo-user] Re: OT: Question re: UUID
· Anthony E. Caudel [EMAIL PROTECTED]: I have noticed in some distros (namely Ubuntu) that the fstab uses UUID's rather than /dev references. Is this a better way? Does it eliminate the problem of /dev references changing when another drive, i.e., an external USB drive, is plugged in? The /dev references may change but the UUID's in fstab wouldn't, would they? Correct. UUIDs are universally unique (as the name already suggests *g*) and thus, there cannot be a clash. Michael Schmarck -- Every journalist has a novel in him, which is an excellent place for it. -- gentoo-user@lists.gentoo.org mailing list
[gentoo-user] Re: OT: Question re: UUID
· Dirk Heinrichs [EMAIL PROTECTED]: Am Montag, den 21.04.2008, 16:37 +0200 schrieb Anthony E. Caudel: I have noticed in some distros (namely Ubuntu) that the fstab uses UUID's rather than /dev references. Is this a better way? Yes. Does it eliminate the problem of /dev references changing when another drive, i.e., an external USB drive, is plugged in? Yes. The /dev references may change but the UUID's in fstab wouldn't, would they? Correct. The other possible way would be to give your devices unique names, either via udev or by using LVM. Advantage over UUIDs: much easier to read. Disadvantage: Not guaranteed to be unique. It could, theoretically at least, happen that there are two devices with the same names. The same disadvantage exists, if you use filesystem labels. Advantage of fs labels: No need for another layer like LVM. Michael Schmarck -- i dont even know if it makes sense at all :) This is an experimental patch for an experimental kernel :)) -- Ingo Molnar on linux-kernel -- gentoo-user@lists.gentoo.org mailing list
Re: [gentoo-user] Re: OT: Question re: UUID
Michael Schmarck wrote: Correct. UUIDs are universally unique (as the name already suggests *g*) and thus, there cannot be a clash. Not quite true, drives in a RAID have the same UUID. Here's my raid5 for an xxample: # blkid | grep mdraid /dev/sdb1: UUID=bf59d132-8b98-7d9c-c526-af1cfb835fa3 TYPE=mdraid /dev/sdc1: UUID=bf59d132-8b98-7d9c-c526-af1cfb835fa3 TYPE=mdraid /dev/sdd1: UUID=bf59d132-8b98-7d9c-c526-af1cfb835fa3 TYPE=mdraid So you would need to reset the UUID before reusing a drive from an array. Have fun, Roy -- gentoo-user@lists.gentoo.org mailing list
Re: [gentoo-user] Re: OT: Question re: UUID
Michael Schmarck wrote: · Anthony E. Caudel [EMAIL PROTECTED]: I have noticed in some distros (namely Ubuntu) that the fstab uses UUID's rather than /dev references. Is this a better way? Does it eliminate the problem of /dev references changing when another drive, i.e., an external USB drive, is plugged in? The /dev references may change but the UUID's in fstab wouldn't, would they? Correct. UUIDs are universally unique (as the name already suggests *g*) and thus, there cannot be a clash. Michael Schmarck Any chance that GRUB will ever use these? I have a sata hd carrier and when I reboot with it plugged in, grub sees the disk order differently and gives me problems (I either have to get a grub command line and boot manually or use a Grub boot floppy). Tony -- Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. -- Benjamin Franklin -- gentoo-user@lists.gentoo.org mailing list
