How to mount extra partitions from a fixit disk

[Jonathon McKitrick]

Here's my scenario: I'm running 4.10 on a laptop, and the drive is in the
process of dying.  It won't boot, but from the fixit disk I am able to
access the root directory.  Root is assigned to ad0s1a, which the fixit disk
has in the /dev directory.  However, /usr is on ad0s1g.  There is no entry
for this device in /dev, and no MAKEDEV script either.  How can I mount this
device/partition to access /usr?

Also, I'm trying to decide how to get the data off the laptop.  I have a wi
card and a parallel port zip drive.  Which would be easier to get working?
Can I simply copy the modules from another 4.10 box and then break into the
boot cycle and load them there?

jm
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