Correct steps to mount an internal backup harddrive

Question

Sorry if this is covered elsewhere, I'm really hoping to get this right first time rather than lose backup information.

I installed Ubuntu 14.04 Final Beta a few days back - during the install, there was a problem installing the MBR to my target drive (/dev/sdb - Samsung 128Gb SSD). The only way around it that I found was following a tutorial that had me boot into the Live USB, install an application that did a guided repair of the MRB - it looks to have installed that on my backup drive (/dev/sda - WD 350Gb HD).

I've installed the 14.04 Release today on /dev/sdb, but to boot it, I need to boot /dev/sda which has the MBR (ie. /dev/sda needs to be first in the BIOS boot order). This "works", but I don't have access to the /dev/sda harddrive to access important backup data.

What I'm guessing I need to do is get the MBR on to /dev/sdb so that it boots independently, then find a way to mount and access /dev/sda - but I'm not sure if the correct method, and I can't afford to lose what's on /dev/sda.

Any help here would be deeply appreciated - I'm reasonably comfortable with basic terminal commands (update, install, remove, navigating directories etc.)

Edit: Here's the output of cat /proc/partitions:

mitch@mitch:~$ cat /proc/partitions
major minor  #blocks  name
   8     0    312571224  sda
   8     1    312570168  sda1
   8     16   125034840  sdb
   8     17   116689920  sdb1
   8     18           1  sdb2
   8     21     8342528  sdb5
   11    0      1048575  sr0

Edit: When using the 'sudo mount /dev/sda1 /mnt/wdhdd' command, I get 'mount: you must specify the filesystem type'.

Thanks heaps,

Mitchell

Edit 2: Output of 'parted -l':

Model: ATA WDC WD3200BEVT-7 (scsi) Disk /dev/sda: 320GB Sector size (logical/physical): 512B/512B Partition Table: msdos

Number Start End Size Type File system Flags 1 32.3kB 320GB 320GB primary boot

Model: ATA SAMSUNG SSD 830 (scsi) Disk /dev/sdb: 128GB Sector size (logical/physical): 512B/512B Partition Table: msdos

Number Start End Size Type File system Flags 1 1049kB 119GB 119GB primary ext4 2 119GB 128GB 8543MB extended 5 119GB 128GB 8543MB logical linux-swap(v1)

Answer 1

If I understand you correctly, you are booting with /dev/sda as the first drive in the BIOS boot order, but are actually loading the system from /dev/sdb. If that is true, all you have to do is mount the correct partition from /dev/sda. You'd do something like this:

mkdir -p /mnt/wdhdd
sudo mount /dev/sda1 /mnt/wdhdd

If you have trouble figuring out which partition on /dev/sda to mount, you could post the output of cat /proc/partitions and we could help you figure it out or you could try some of the larger partitions.

Edit: With your setup, you'll want to mount /dev/sda1, and I've modified the commands above.