Question 1
On modern networked computers, maintaining the correct time on each machine is important. Computers on a LAN or WAN with di erent times can cause problems. In about a page and in your own words explain why it is important for computers to maintaining the correct time and more importantly explain how do they do it.
In your explanation make certain to include discussions on the following linked topics:
The computer's hardware clock (also called the Real Time Clock or RTC)
The computer's software clock (also called the kernel or system clock)
In Linux, how they are syncronised and why do they need to be syncronised? (See Exercise 2.35 from the Study Book) What is UTC and why is it used? (UTC: Coordinated Universal Time, or Temps Universel Coordonne, and if you want|you can explain what is going on with the acronym!)
What is NTP and what are \clock strata"?
Notes:
a. The topics above are linked to each other and the question, they are not independent of each other. They are provided as a minimal guide only. Do not simply write an unconnected paragraph on each without linking the concepts together.
b. List all resources used in answering this question.
c. Please do not cut and paste slabs of text from a Wikipedia article. The question explicitly says in your own words!
d. Please do not fall into the trap of answering the question by using unexplained technical terms|you must explain all technical terms used especially if they have not been used anywhere else in the course.
Question 2
A user comes to you and explains that she needs some form of encrypted le system to store sensitive information on a Flash drive. The Flash drive will be used to transport the sensitive data between work and home and she is worried about loosing the drive and having the data stolen. Both machines, the one at home and the one at work, use the same Linux OS.
She has the following requirements:
She does not want to encrypt individual les as she has to deal with a large number of les.
She wants it to be as transparent as possible.
She thinks she will only need about 64MB at most.
She wants to also use the ash disk for transporting unencrypted les. Files that can be read on machines apart from her work and home machines.
A 64MB le that contains an encrypted le system, stored on the Flash drive would appear to be ideal|
a. Create a 64MB encrypted le system in a leon a Flash drive so that it can be used with the cryptmount command.
Document and explain in your own words every command you use (plus any command line options) and any con guration les you modify or create. Your descriptions of each operation need to show you understand the purpose of the operation.
Note: If you are uncertain why a particular command or command line option is required|ask! There is at least one step and command line option that you cannot understand from the information in the man page alone! It will require some research!
b. Things you must also address and explain:
how to ensure that the Flash drive has exactly the same mount point each time it is used on di erent machines. If it does not have the same mount point then how do you con gure cryptmount paths? Hint: Experiment with \labelled" le-systems (see the command e2label or dosfslabel) or UUIDs in conjunction with the le /etc/fstab how to manage the le-system encryption keys.
c. Write an instruction sheet for the user so that she can make the modi cations to her home machine so that she can access the le on the ash drive containing the encrypted le system. Also explain how she would use the lesystem in her day-to-day work.
You may assume that she has root access to be able to con gure her home machine to mount an encrypted le-system.
a. Do not use the tool cryptmount-setup or the tool installed by the package cryptsetup.
b. Manually create les and con guration les.
c. Follow the steps outlined in the cryptmount man page| explaining the purpose of every step!
d. List all resources used in answering the question.
e. Do not explain how you installed the cryptmount package|it should already be installed on the Virtual Debian.
Question 3
You have been asked to install an SVN repository on a server. The SVN will be remotely accessed using the svnserve dmon that is supplied with SVN (please note that this is not the most secure way to access an SVN repository) Install the distributed revision control system subversion from the Debian package of the same name. After installation you will need to con gure subversion to be usable.
Tasks that will need to be done:
a. Install the subversion package.
b. Write and install an init.d script to automatically start and stop svnserve (the subversion server) at boot/shut-down (in dmon mode| do not use inetd mode, do not use an ssh encrypted tunnel). (Hint: Use the example init script /etc/init.d/skeleton and remember to
explain your changes.)
c. Create an SVN repository at /usr/local/svn/
d. Con gure the repository and de ne the repository usernames and passwords.
e. Implement con guration and runtime options that increase security|explaining why your choices increase security.
f. Test your con guration, repository and running server by creating a project in the repository. Show that you can check in and check out documents from the repository.
(Note: this is supposed to be a remote repository so all tests must be done via the svn server.)
g. Document and explain in your own words the steps required to get the subversion system working. Include an explanation of every command you use (plus any command line options) and any les you modify or create. Your descriptions of each operation need to show you understand the purpose of the operation.