It seems following that guide, and doing the initramfs update sorts it...
The slug fails to reboot with 2 drives connected
If you connect a second drive after you have installed Debian, for example to store your data files, the order of the drives will be random after rebooting, i.e. the new drive could become /dev/sda with your root filesystem being /dev/sdb. If that happens the slug will fail to boot because it will be looking for its root filesystem on the wrong disk. To recover, boot with only the root drive connected and change your fstab to mount your root drive by UUID by following the procedure outlined below.
List the UUIDs of your drives with the tree (apt-get install tree) command
$ tree /dev/disk
| |-- usb-[=ST340014=]_A_5000000000002886 -> ../../sda
| |-- usb-[=ST340014=]_A_5000000000002886-part1 -> ../../sda1
| |-- usb-[=ST340014=]_A_5000000000002886-part2 -> ../../sda2
| `-- usb-[=ST340014=]_A_5000000000002886-part5 -> ../../sda5
| |-- pci-0000:00:01.2-usb-0:1:1.0-scsi-0:0:0:0 -> ../../sda
| |-- pci-0000:00:01.2-usb-0:1:1.0-scsi-0:0:0:0-part1 -> ../../sda1
| |-- pci-0000:00:01.2-usb-0:1:1.0-scsi-0:0:0:0-part2 -> ../../sda2
| `-- pci-0000:00:01.2-usb-0:1:1.0-scsi-0:0:0:0-part5 -> ../../sda5
`-- 424ba820-8e80-422e-aaeb-b343b4a462f1 -> ../../sda1
and then modify your fstab by replacing /dev/sda1 (your root partition) with the UUID, e.g.
# /etc/fstab: static file system information.
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc defaults 0 0
UUID=424ba820-8e80-422e-aaeb-b343b4a462f1 / ext3 defaults,errors=remount-ro 0 1
/dev/sda5 none swap sw 0 0
/dev/sda1 /media/usb0 auto rw,user,noauto 0 0
/dev/sda5 /media/usb1 auto rw,user,noauto 0 0
Then update the initramfs:
$ sudo update-initramfs -u
and flash the new initramfs
$ sudo flash-kernel
You may want to make a copy of your existing flash before this last step in case something goes wrong.
Right, im having trouble with it not always booting up with the 2nd drive attached...
It worked fine a few times before I changed it, but its not working now...
Another user on IRC is having the same problem – He’s also made the changes as per that post above, and its still not working
Anyone got any other suggestions?