=== Try and boot the UML instance with the root mounted read-only. Any problems? ===
No. The UML instance can startup normally. Only issue is that the whole file system became read only, not even the tmp files or log files can be written back to the system.

== What are the command line options ==
<code bash>
linux.uml rootfstype=hostfs rootflags=/home/vic/uml/ r 
</code>
By removing the w option (r instead of rw), we have the file system of UML instance read-only.

=== Briefly explain the inittab configuration format ===

<code>
1:1:respawn:/etc/getty 9600 tty1
</code>
Given the above example, it is easier to expain the format.
  * id - you can give an ID to the configuration line, but it is optional
  * run level - the second colon is the run level, indicates in which run level// s // the device will be initiated. 
  * behavior - this indicate what to do in case the process stop or hang
  * path to dev - path to the dev file
  * parameter - in this case the MTU
  * name - in this case the tty1
  
reference 
http://linux.about.com/od/commands/l/blcmdl5_inittab.htm
=== use ramfs. Have /tmp be a symlink to /var/tmp ===
Please see the work log

== Why these directories and what are they for ==
These are the system files needed for the bare linux to be properly run and log all the errors and information.
  * /lock - lock files, indicate which files are being locked by whom, avoid concurrent conflict
  * /tmp - temp files generated during the execution of the processes
  * /log - most log files are kept here by default
  * /run - current running processes

=== investigate the screen program ===
see the work log

=== add a virtual console to each UML instance ===
see the work log

=== setup up to four ethn devices in script ===
done. see the work log host script

=== add case switch for different roles ===
done. see the work log guest rcS script

=== recreate the simple network in assignment 2 ===
done. see the work log