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Re: [LUG] Disk order swap at boot

 

Tom Potts wrote:
> On Wednesday 10 September 2008 00:22, Grant Sewell wrote:
>   
>> Rob Beard wrote:
>>     
>>> Tom Potts wrote:
>>>       
>>>> I had a machine with Suse10.1 installed on a PATA hard drive.
>>>> I've inserted a SATA drive and when installing Ubuntu I found I had to
>>>> tell the bios to use the SATA as the first hard drive to stop the Ubuntu
>>>> (64bit alternate) using the PATA drive swap first.
>>>> Now the Ubu works fine but I cant boot into Suse10.1 for the Ubu grub
>>>> unless I hit the bios to swap the drives around again, or edit all the
>>>> suse menu.lst drive references.
>>>>
>>>> Does anyone know of a way I can tell linux (in either setup) which order
>>>> to see the disks?
>>>>
>>>> Tom te tom te tom
>>>>         
>>> Not sure if it helps, but I think you could do with using UUID's.  From
>>> what I understand, each partition has it's own unique UUID which is
>>> something like 20 characters.  Ubuntu (at least the recent versions
>>> 7.04, 7.10, 8.04 I think) use UUID's in FSTAB to decide what to mount
>>> and where.  I'm not sure exactly how to find out the UUID's of the Suse
>>> partitions but I'm sure a Google search will help.
>>>
>>> Rob
>>>       
>> If you know the current Linux partition name (hdXY or sdXY) then it's
>> relatively easy to find out what the UUID is.  Simple go to:
>>
>> /dev/disks/by-uuid
>>
>> and you should find some symlinks to the actual device names.  For
>> example, on my desktop system I have:
>>
>> 70b4945e-eb7f-40cf-ad51-2325230d02b7 -> ../../sdb1
>> c27d80ae-3749-418a-9133-27b8a8903339 -> ../../sda1
>> d88fc3eb-34c7-4b7a-ae4c-f38a727cccc6 -> ../../sdb5
>>     
> And for the lazy - how do I 'adjust' them at boot time - in Menu.lst for grub 
> or elsewhere?
> Tom te tom te tom
>   
>> Please note that different partitions/filesystem types have different
>> length UUIDs.
>>
>> Grant.
>>     
Edit the kernel lines.  Rather than having "root=sda6" it should say 
something line "root=UUID=blah-blah-blah

You may also need to edit your fstab files on both OSs.

Grant.

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