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
linux.uml rootfstype=hostfs rootflags=/home/vic/uml/ r
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
1:1:respawn:/etc/getty 9600 tty1
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
