[libvirt-users] Different SAS controller IDs

[Anton Nikiforov]

12.07.2012 14:20, Daniel P. Berrange пишет:
> On Thu, Jul 12, 2012 at 02:09:12PM +0400, Anton Nikiforov wrote:
>> Dear All,
>>
>> I have problem with setting up migration on Intel Multi-Flex server.
>> The problem is that SAS controller IDs (and volume ids in
>> /dev/disk/by-path directory) are different between nodes.
>>
>> For example on node0 i have:
>> lrwxrwxrwx 1 root root  9 Jun 29 07:20
>> pci-0000:04:00.0-sas-0x500015500002040a-lun-0 -> ../../sda
>> lrwxrwxrwx 1 root root 10 May 27 09:17
>> pci-0000:04:00.0-sas-0x500015500002040a-lun-0-part1 -> ../../sda1
>> .......
>>
>> On node1 i have:
>> lrwxrwxrwx 1 root root  9 Jul 12 21:19
>> /dev/disk/by-path/pci-0000:04:00.0-sas-0x5000155000020409-lun-0 ->
>> ../../sda
>> lrwxrwxrwx 1 root root 10 Jul 12 21:19
>> /dev/disk/by-path/pci-0000:04:00.0-sas-0x5000155000020409-lun-0-part1
>> -> ../../sda1
>> ........
>>
>> Difference is in 0x500015500002040a and 0x5000155000020409
>> But this is the matter of migration falure because migration script
>> cannot find needed volume.
>>
>> Is there any chance to fix it somehow?
>
> Have you tried using /dev/disk/by-id/ aliases instead ?  IIRC, those are
> based on the SCSI volume WWID which should be stable across any host
> seeing the LUN
>
> Daniel
>
Hello Daniel, All.

Thanks for fast replay.
This is the fastest solution but it have disadvantages, for example: 
there is no way to determine which lun connected to which host (from 
virt-manager side).
This solution require to check /dev/disk/by-path to find there needed 
lun then check /dev/disk/by-id to find there corresponding link and then 
connect it to the host.
I think that should be a solution to change by-path links to what is 
needed by some kind of substitution in storage xml file....
But if using by-id links is the only way - i'll have to live with it.

Best regards,
Anton Nikiforov