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Problem with external RAID



Hi,
I've been fighting a couple of days trying to set up a debian machine and an 
external RAID to work with debian. 
The configuration is:
A dell poweredge 850 server with two serial ata drives. 
A LSI PCI SCSI Controller, that works under linux.
a EonStor RAID, connected to the scsi controller using a cable.

the thing is, after using the last kernel, we managed to make the scsi card 
work correctly. Apparently there are some bugs in the previous versions of 
the kernel/drivers for the scsi card that create some problems when trying to 
access a device. We had those with an earlier version of the kernel and got 
it fixed by using 2.6.17.4.

So, we are using etch on this server in order to recognize all the hardware. 
Everything is working flawlessly (apparently). The sata drives are mapped by 
default to /dev/sda and /dev/sdb and that's how we installed debian. But the 
problem arises when we connect the external RAID to the system. 
The thing is that the system randomly assigns the device /dev/sdc and /dev/sda 
to the RAID, so, sometimes it boots perfectly (when it is /dev/sdc) and some 
others, the boot process aborts (when it is /dev/sda) because the linux is 
not finding the / partitions (as the sata disks are now located at /dev/sdb 
and /dev/sdc).

From what I have been reading, the system loads the modules asynchronously 
using udev (I guess) and so that's why the RAID is assigned /dev/sda 
or /dev/sdc. I've been trying to figure out how to set the order at which I'd 
like the modules to be loaded, but with no luck. I've been trying to define a 
couple of rules at /etc/udev/rules.d/ in order to change the devices 
assigned, but all I get are some symlinks to the real devices in /dev but the 
problem continues to be there.

So, I would really appreciate if someone could give some hints on how to alter 
the order at which the devices are defined as I am a little bit lost.
I don't know if it has something to do with initrd images, or udev, hotplug or 
the order at which the modules are loaded at boot time. Any hint would be 
appreciated, ;) really.

I've also been thinking about getting rid of udev, but I don't want to create 
a complete mess as I don't really know if this is really I should be doing.

-- 
Jesús Roncero Franco
http://localhost



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