Problem with random disks mount sequence

[Les Mikesell]

Lamar Owen wrote:

>> I'm starting to build a box that will have an assortment of scsi and
>> sata disks, most, but not all paired in md raid1 devices and expect to
>> have a few hotplug sata and external USB and firewire drives that will
>> be connected periodically.  Do you have any hints on how to write a
>> script that will copy things to the recently-mounted drive(s) and how to
>> avoid boot problems if any of them happen to be connected during a
>> reboot?  Will the md devices always find/pair themselves regardless of
>> the underlying partition device names?
> 
> MD devices will find their mates by UUID.  Drive order matters not to MD.

Hmmm, maybe I'll create even the non-mirrored partitions as raid1 with a 
'missing' partition to keep things consistent then.  That also has the 
advantage of permitting easy conversion to mirrored or syncing with a 
swappable device that can be removed as a backup.

> The only place where drive order matters is where /boot lives, and that's set, 
> for PC hardware, in the GRUB configuration.

That will be on SCSI, and I think the system bios settings will take 
care of that part.

> 
> Oh, in case your wondering what sort of hardware this is, here's the contents 
> of /proc/scsi/scsi: the clues you need to find out what kind of system this 
> is are in there. :-)
> [root at spacely ~]# cat /proc/scsi/scsi

> Host: scsi0 Channel: 00 Id: 03 Lun: 00
>   Vendor: SEAGATE  Model: ST39103LCSUN9.0G Rev: 034A
                                      ^^^
> [root at spacely ~]#   
> 
> I have had more problems with drive order on PC hardware than I have had on 
> spacely.

But wouldn't you rather be running zfs on that?

-- 
   Les Mikesell
    lesmikesell at gmail.com