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#246193 - 11/01/2005 01:56 More Linux fun - scsi driver load order
rob
carpal tunnel

Registered: 21/05/1999
Posts: 5335
Loc: Cambridge UK
Is it possible to force Linux to assign drivers for two scsi cards in a particular order *without* switching to modules? Since adding a second scsi controller to a server my scsi0 and scsi1 assignments are now backwards.

Ta

Rob

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#246194 - 11/01/2005 02:01 Re: More Linux fun - scsi driver load order [Re: rob]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14496
Loc: Canada
Probably not.

But if you use volume labels instead of hardcoded device names in /etc/fstab, then the order won't matter to anything. Ditto for the even more modern LVM volumes.

Cheers

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#246195 - 11/01/2005 03:34 Re: More Linux fun - scsi driver load order [Re: mlord]
rob
carpal tunnel

Registered: 21/05/1999
Posts: 5335
Loc: Cambridge UK
Thanks, that's handy! It doesn't work in grub or for swap, but it will simplify things each time the disk configuration changes.

Rob

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#246196 - 11/01/2005 06:55 Re: More Linux fun - scsi driver load order [Re: rob]
andym
carpal tunnel

Registered: 17/01/2002
Posts: 3996
Loc: Manchester UK
I recently had this problem, I've got two SATA discs and a internal USB card reader. I found that the card reader was being detected first and being assigned sda through sdd and sde & sdf were the discs. I felt rather uneasy that a failure to detect the card reader on boot would mess up the allocation of the discs. I ended up compiling USB as modules and modprobing at startup, that way the discs are always sda and sdb.

EDIT: Looking at Marks post, I might give that a try, I'm using LVM but I've kept my / on a normal partition.


Edited by andym (11/01/2005 09:50)
_________________________
Cheers,

Andy M

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#246197 - 11/01/2005 11:41 Re: More Linux fun - scsi driver load order [Re: rob]
JBjorgen
carpal tunnel

Registered: 19/01/2002
Posts: 3584
Loc: Columbus, OH
This may sound retarded, but have you tried changing the order of the scsi cards in the pci slots? I don't know how linux goes about detecting and assigning stuff, but methinks that used to work for dos/win9x.
_________________________
~ John

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#246198 - 11/01/2005 12:10 Re: More Linux fun - scsi driver load order [Re: rob]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14496
Loc: Canada
Oh yeah. Grub.. bleeding bootloaders can be so troublesome at times!

But yes, try rearranging the arrangement of SCSI adapter cards within PCI slots (if possible, more likely you've got some mainboard interfaces in this mess).

Actually, I'm not sure that Grub would be a big issue -- it needs a physical partition anyway, and uses BIOS drive numbering. So if Grub even loads from the "first" BIOS disk (0x80), then it should be able to find its own files on hd(0,*) without much issue -- just ensure that the kernel and initrd files are all under /boot on a physical partition with /boot/grub/* -- this is the default for most distros.

The root=xxx kernel parameter in grub.conf (or lilo.conf) can be anything, including a volume device path, or a LABEL=/ designation.

I had something similar go screwy on my WinXPpro install -- MS decided my flashcard reader slots each represented a disk drive, and lettered them all before the real drive. So my files are all now installed on drive "I:", but some of the default prompts when installing s/w still ask for "C:" and have to be fixed by hand each time.

Cheers


Edited by mlord (11/01/2005 12:11)

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#246199 - 11/01/2005 13:41 Re: More Linux fun - scsi driver load order [Re: mlord]
tman
carpal tunnel

Registered: 24/12/2001
Posts: 5528
Quote:
I had something similar go screwy on my WinXPpro install -- MS decided my flashcard reader slots each represented a disk drive, and lettered them all before the real drive. So my files are all now installed on drive "I:", but some of the default prompts when installing s/w still ask for "C:" and have to be fixed by hand each time.


Ah yeah. The fun of built in card readers. Unplug them before installation and it'll be fine. Once you've installed Windows, you can plug them back in and they'll get detected and put into the proper place.

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#246200 - 11/01/2005 15:07 Re: More Linux fun - scsi driver load order [Re: mlord]
bonzi
pooh-bah

Registered: 13/09/1999
Posts: 2401
Loc: Croatia
Quote:
I had something similar go screwy on my WinXPpro install -- MS decided my flashcard reader slots each represented a disk drive, and lettered them all before the real drive. So my files are all now installed on drive "I:", but some of the default prompts when installing s/w still ask for "C:" and have to be fixed by hand each time.

You might not know that one can change drive letter mapping in XP (contol panel, admin tools, computer management, disk management).
_________________________
Dragi "Bonzi" Raos Q#5196 MkII #080000376, 18GB green MkIIa #040103247, 60GB blue

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#246201 - 11/01/2005 15:15 Re: More Linux fun - scsi driver load order [Re: bonzi]
tman
carpal tunnel

Registered: 24/12/2001
Posts: 5528
Don't think that works for the boot drive though.

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#246202 - 11/01/2005 16:29 Re: More Linux fun - scsi driver load order [Re: mlord]
rob
carpal tunnel

Registered: 21/05/1999
Posts: 5335
Loc: Cambridge UK
Quote:
But yes, try rearranging the arrangement of SCSI adapter cards within PCI slots (if possible, more likely you've got some mainboard interfaces in this mess).

One of the controllers is a RAID card that has a direct interface with the on-board SCSI channels, so it has to be in a particular slot. Not a problem though, everything except swap is now set to update automatically if I reconfigure.

Quote:
The root=xxx kernel parameter in grub.conf (or lilo.conf) can be anything, including a volume device path, or a LABEL=/ designation.

That's the bit I didn't know - very useful!

It's all working nicely now, thanks for your help.

Rob

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#246203 - 11/01/2005 17:41 Re: More Linux fun - scsi driver load order [Re: rob]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14496
Loc: Canada
Quote:
Quote:
>The root=xxx kernel parameter in grub.conf (or lilo.conf) can be anything, >including a volume device path, or a LABEL=/ designation.

That's the bit I didn't know - very useful!



I remember "discovering" this for myself the first time I installed FedoraCore onto a second partition on a system that also had Redhat9 on on the first partition..

Both of them use "root=LABEL=/", and both of them used "/" as the label for their root partitions.. so on reboot, grub loaded the Fedora kernels for me, but then tried to use the Redhat9 root partition.. duh!

I notice that FedoraCore3 seems to no longer be quite so dumb about it.

Cheers

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#246204 - 14/01/2005 17:42 Re: More Linux fun - scsi driver load order [Re: andym]
Memil
member

Registered: 03/02/2002
Posts: 101
Loc: Sweden
I think you could solve this with udev also, you can do amazing things there...
My usb-stick(former /dev/sda1) is always named /dev/cruzer now... :-)

... lvm rocks also, just reinstalled our mailserver to use lvm so we could use the snapshot-function to minimize the backuptime...

/Fredrik

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