tail of two scsis

[Richard Emberson]

Well riddle me this:

Last night I turned on the machine and the bios magically found the
second scsi disk, disk B.
(I spent the next hour backing it up onto other systems :-)

So, the disk kind of comes and goes; sometimes its there and sometimes
its not.

Richard

Jose Luis Ricardo Chavez wrote:
> Richard Emberson wrote:
> 
>> Jose Luis Ricardo Chavez wrote:
>>
>>> Richard Emberson wrote:
>>>
>>>> Jose Luis Ricardo Chavez wrote:
>>>>
>>>>> Richard Emberson wrote:
>>>>>
>>>>>> I've got a FC2 system and a scsi disk with /boot and /.
>>>>>> In addition, I have two other scsi disks with /home and /usr/local
>>>>>> on them (call the disks A and B). Both of these disks
>>>>>> have their IDs set to 6.
>>>>>> When I boot the system with disk A, disk A can be found and
>>>>>> the boot succeeds. When I replace disk A with disk B, disk B
>>>>>> can not be found and the boot fails.
>>>>>> Other than the possibility that disk B is bad, what else
>>>>>> could be the cause?
>>>>>>
>>>>>> The boot disk is a 7500rpm Quantum.
>>>>>> Disk A is a 10000rpm Maxtor.
>>>>>> Disk B is a 7500rpm Quantum.
>>>>>> Back in my RedHat 9 days, the system used both Quantum disks.
>>>>>>
>>>>>> Thanks
>>>>>>
>>>>>> Richard
>>>>>>
>>>>>>
>>>>> Are both disks using the same SCSI id while connected to the same 
>>>>> cable
>>>>> (SCSI channel)? As far as I remember there is not a "cable select" 
>>>>> option
>>>>> when using SCSI disks, both disks should use different id's. Put 
>>>>> the lowest
>>>>> id on the boot disk (A). If the disks are connected to different 
>>>>> SCSI channels
>>>>> then maybe there is a problem with one of them.
>>>>> - Jose Luis
>>>>>
>>>>>
>>>> The boot disk is always on the cable. Only one of the disks A and B
>>>> are on the cable at one time.
>>>>
>>>>
>>> Ok, you have three disks, the boot disk is permanently connected and 
>>> you connect
>>> disk A or B when needed. Is the SCSI BIOS detecting disk B?
>>
>>
>>
>> No.
>> It detects disk A (disk B not connected) but not disk B (disk A not 
>> connected).
>> The boot disk in both cases is detected.
>>
>>>
>>> - Jose Luis
>>>
>>>
>>
>>
> Well, it seems disk B is damaged.
> 
> - Jose Luis
> 
>