1. Find out, which (possibly virtual) devices are mounted in directory structure.. Have a look into /etc/fstab and compare its contents to your recent findings. Also, examine contents of /dev directory and note, what devices are in there. Which ones correspond to the disks on this virtual computer? 2. Device /dev/ubdc corresponds to the CD-ROM of your virtual computer. Mount it somewhere and have a look at files on it. Try also options "norock", "nojoliet", "mode", "uid" and also "ro" (!) when mounting it. 3. How could you attain, that all users belonding to the group "zelenina" couldmount CD, which they insert into this (even though only virtual) CD-ROM? Is it neccessary to use any specific options (if so, which ones?) to not make an easily exploitable security hole to your system? Try various options for mounting this drive -- amongst the most interesting are e.g. "nosiud", "noexec", "nodev" and "ro". Try whether their description in "mount" manpage corresponds to the reality. 4. Create a device with some suitable name (e.g. "/home/zahrada/kombajn" (slovak word for 'harvester)), which will work exactly like a standard disk /dev/ubda. See if it really behaves they way you would expect. 5. Amongst interesting devices there are /dev/null and /dev/zero. Of what use are they? What is the difference between them? Another two interesting devices are /dev/random and /dev/urandom? How do they differ? 6. You just bought a new hard drive with hypermodern capacity 5MB and connected it to your computer. Your virtual computer found it as a device /dev/ubdb. To have some reasonable data stored there, you should probably create some filesystem on it. Do you have any idea, which one? And also, how to put it on that drive? ---- (and some extra assignments for those worried about not having anything to do) 7. In order to not mount your hard drive every reboot by hand, append to proper configuration file a line, which causes to have it mounted automagically on proper mountpoint every boot. 8. As you might already know, backups are very important. How would you back up contents of this drive? The easiest way would be just copying its contents to some file. Try it! There are many solutions and one of them is to use the "dd" command. Have a look on its manual page and try using it to solve this assignment. Also, try executing 'file', which can tell you some useful information about files or directories. 9. How can we not tell whether the backup really works as expected? Easiest way could be to just mount the file with backup. Is it even possible? If you manage to do it, check for all the files, which were on your hard drive. Don't forget that you don't want to break your backup, so it is recommended to mount it read-only! The keyword for this assignment is "loop".