FreeBSD mount new drive:


Pulled out hard drive and stuck in another machine. Error received:

Trying to mount root from ufs:/dev/ad0s1a

Manual root filesystem specification:
  <fstype>:<device>  Mount <device> using filesystem <fstype>
                     eg. ufs:da0s1a
  ?                  List valid disk boot devices
  <empty line>       Abort manual input


Boot messages reveal that hard drive has switched to:
ad4: 95396MB <Hitachi ....>....

mountroot> ufs:/dev/ad4s1a
/ is now mounted.

Need to mount /usr for some tools (eg. vi) (-w = write)
mount -wt ufs /dev/ad4s1f /usr 

Update /etc/fstab with the new drive/partition locations
In this case change all /dev/ad0... to /dev/ad4...

If you get errors about read only filesystem:
mount /
This should remount / with rw