I believe thats why there are persistant superblocks on the RAID partitions. You can switch them around, and it still knows which drive holds which RAID partition... That's the only way booting off RAID works, and the only reason for the "RAID Autodetect" partition type... you can find those shuffled partitions correctly. The only time it really looks at the file, is if you try to rebuild the partition I believe... and some other circumstance that dosn't come to mind. Sam Bingner -----Original Message----- From: Alex Bligh - linux-kernel [mailto:[EMAIL PROTECTED]] Sent: Tuesday, May 15, 2001 11:30 AM To: Linus Torvalds; Jonathan Lundell Cc: Jeff Garzik; James Simmons; Alan Cox; Neil Brown; H. Peter Anvin; Linux Kernel Mailing List; [EMAIL PROTECTED]; Alex Bligh - linux-kernel Subject: Re: LANANA: To Pending Device Number Registrants > The argument that "if you use numbering based on where in the SCSI chain > the disk is, disks don't pop in and out" is absolute crap. It's not true > even for SCSI any more (there are devices that will aquire their location > dynamically), and it has never been true anywhere else. Give it up. Q: Let us assume you have dynamic numbering disk0..N as you suggest, and you have some s/w RAID of SCSI disks. A disk fails, and is (hot) removed. Life continues. You reboot the machine. Disks are now numbered disk0..(N-1). If the RAID config specifies using disk0..N thusly, it is going to be very confused, as stripes will appear in the wrong place. Doesn't that mean the file specifying the RAID config is going to have to enumerate SCSI IDs (or something configuration invariant) as opposed to use the disk0..N numbering anyway? Sure it can interrogate each disk0..N to see which has the ID that it actually wanted, but doesn't this rather subvert the purpose? IE, given one could create /dev/disk/?.+, isn't the important argument that they share common major device numbers etc., not whether they linearly reorder precisely to 0..N as opposed to have some form of identifier guaranteed to be static across reboot & config change. -- Alex Bligh - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
RE: LANANA: To Pending Device Number Registrants
Bingner Sam J. Contractor RSIS Tue, 15 May 2001 16:44:57 -0700
- Re: LANANA: To Pending Device ... James Simmons
- Re: LANANA: To Pending Device Numb... Miles Lane
- Re: LANANA: To Pending Device ... Oliver Neukum
- Re: LANANA: To Pending Dev... Tim Jansen
- Re: LANANA: To Pending Dev... David Brownell
- Re: LANANA: To Pending Device ... David Brownell
- Re: LANANA: To Pending Device ... James Simmons
- RE: LANANA: To Pending Device Number Regist... Bingner Sam J. Contractor RSIS
- Re: LANANA: To Pending Device Number R... Andrzej Krzysztofowicz
- Re: LANANA: To Pending Device Numb... Richard Gooch
- RE: LANANA: To Pending Device Number Regist... Bingner Sam J. Contractor RSIS
- RE: LANANA: To Pending Device Number R... Alex Bligh - linux-kernel
- Re: Re: LANANA: To Pending Device Number R... Tim Jansen
- RE: LANANA: To Pending Device Number Regist... Chemolli Francesco (USI)
- Re: LANANA: To Pending Device Number R... Helge Hafting
- Re: LANANA: To Pending Device Numb... Oystein Viggen
- Re: LANANA: To Pending Device ... Josh Fryman
- Re: LANANA: To Pending Device ... Helge Hafting
- Re: LANANA: To Pending Dev... Miles Lane
- Re: LANANA: To Pendin... Michael Meissner
- Re: LANANA: To Pe... Stephen C. Tweedie