Sample questions for Exam #2

Please explain the purpose of each of the following network tools: ping, traceroute, and netstat.
Contrast the uses of MAC and IP addresses in the network process.
Name the five layers of the TCP/IP network stack
Briefly explain the difference between a user agent (MUA), a delivery agent (DA), and an access agent (AA)
What is inetd?
What is the point of a pillar in SaltStack?
Describe the automount process. Give 3 valid reasons as to why an automounter is important to have on your machine.
Name the 3 elements that determine file-level access in NFS.
What type of file does this resemble?
/ master(rw) trusty(rw,no_root_squash)
/projects proj*.local.domain(rw)
/usr *.local.domain(ro) @trusted(rw)
/home/joe pc001(rw,all_squash,anonuid=150,anongid=100)
/pub (ro,insecure,all_squash)
Bob receives a threatening email from an account "Alice@anonymous.com" and wishes to trace this email back to the original sender so that he may report the creator of Alice@anonymous.com to the authorities. What critical information does Bob want to investigate? How will he obtain this information, and what commands can he use to retrieve further information about the email?
What is a daemon?
How does a web proxy server better response time for requests?
What is delegation for a nameserver? Give a simple example.
What are the necessary tasks for a mail server?
What is one benefit of using a proxy web server?
List three kinds of internet daemons and briefly explain their purpose.
What is an advantage and disadvantage of recursive DNS queries?
What benefits can a user have by using a web proxy?
Describe a NAT network.

Additional suggested questions from prior years:

Suppose you have a new company that needs to have access to and transfer files across networks securely. What method would you use to do so and why?
What is the purpose of using a mail queue for outbound messages and why is it a good idea for it to be spooled?
Is TCP or UDP a more reliable way of sending packets? Which is faster? Why?
How does inetd know to start a certain daemon?
Name 2 typical forms of network topology.
What are the 5 layers of the TCP/IP network stack?
Compare and contrast the centralization and decentralization of networks.
What is the /etc/exports file?
How are inetd and xinetd are the same? How are they different?
Name three daemons and what they are responsible for.
What kind of data does a magic cookie usually contain?
Name one of the four main mail agents, its primary function, and give an example of a program that does this
What is the difference between name based and ip based virtual hosting?
Explain how NFS uses a UID to grant permissions to files when mounting. Discuss any security problems, if any, associated with this method and their solution(s).
Explain why routers are "intelligent" switches
What are the different types of DNS name servers and how are they different?
Explain the difference between a recursive vs a nonrecursive server, and how each is used in the resolution process.
What are some of the disadvantages to NFS servers being stateless?
You've just created a folder with family pictures that you'd like to share with your family on your recently configured NFS server. Which file would you edit (or create) to accomplish this?
What is the difference between and authoritative and a caching server? Why not just use authoritative name servers?
Which of the following contains the NFS mounts for boot time?
a./bin/mount.conf
b./etc/fstab
c./bin/NFSboot
d./etc/exports
While running grub, what commands should be entered to reset the master boot record to it's original configuration?
Describe the difference between a DNS PTR record and a CNAME record.
List 4 types of namespace policies a SA should have and briefly describe what they are for.
What are the components of a URL address? Why isn't the port address of the service requested normally not included in the URL?
What are the four components of the e-mail system?
From our first project, what are the steps taken to modify your grub file to set up an .iso of another operating system?
What is the relationship between BIND and 'named'?
What programs might a typical email message pass through as one unix/linux user emails another and what do they do?
What are some important factors to consider when scheduling maintenance windows?
Write a simple zone file for domain studentgets100.com with IP address of local host with hosts "yes", and "ofcourse".
What should you do to provide a 'Truly robust DNS environment' and why?
What is an advantage of using centralization with server hardware?
What is the account name used for a "squashed" root user on a NFS Server?
Why is it important not to use vendor-installed operating system configurations?
Imagine your machine is on a network that has no working DNS or NIS, and your /etc/fstab is configured to mount filesystems from other machines using their DNS names. You know what IPs correspond to the entries in the /etc/fstab. How can you make the filesystems mount normally without changing your /etc/fstab?
What is the purpose of the command netstat?
What DNS method can be used by a machine to reduce DNS load? Explain.
What is the difference between TCP and UDP, and explain where one might be more appropriate than the other.
Why are root and top-level domain servers nonrecursive?
What are the benefits and detriments of a caching DNS server?
What is the name of at least one email delivery agent that we have gone over in class or in the readings?
What is the daemon that manages other daemons?
What is CIDR and what notation is used for CIDR?
T/F. If Bob and Mary share the same UID on two separate clients, they will have access to each other's NFS files?
True/False : the email address used in the from address part of an email must be the same as the email address used in the MTA/SMTP handshake.
As a system administrator, it may be important to block web access to some sites. How could this be accomplished using a proxy cache? Give an example to block all access to sites within the google.com domain.
Suppose a user has trouble accessing a website hosted on a name-based virtual host. How could this occur?
How does DNS solve scalability problems?
What are some of the security problems associated with NFS and how can these issues be avoided?
Give the path of the sendmail configuration file which can be modified.
Explain how the DNS A and PTR records can provide a level of authentication.
The following commands are executed, in the following order:
```
touch tmp1
ln tmp1 tmp2
ln -s tmp1 tmp3
ln -s tmp2 tmp4
rm tmp1
```
What will be the state of the files (tmp1, tmp2, tmp3, tmp4)?
Describe the 5 network layers.
What is sendmail's configuration file?
What is DHCP and how does it work?
What are the advantages of CIDR (Classless Inter-Domain Routing)?
What steps must be taken to use a CGI script in Apache?
Why is it necessary for you to update the /etc/resolv.conf file each time you boot up your sandbox drive in order for it's associated service to function correctly?
What does the command 'netstat -rn' do? What are at least 2 other uses for the netstat command?
What are the advantages and disadvantages of automounting an NFS?
What are some advantages to having a local proxy server on your network?
If a packet of size 576 encounters a router with an MTU of 1500, which of the following would occur?
a) The packet would go through an IP fragmentation
b) There will be many acknowledgments being sent and handled due to the data to header ratio
c) The packet is sent back to the sender
d) None of the above
What is NFS's no_root_squash export option and why can it be dangerous?
How are the client mount points and the exported file systems tracked on the server?
Name at least 4 Top-Level Domains in the U.S. and what they are used for; Name at least 3 types of records found in a zone file and what they are for.
With NFS, what is typically used to prevent users with root access on a client from gaining access to any file? How does it work?
What are the 5 network layers and what do those layers contain?
What are some advantages of using a caching proxy server?

Last revised: 12 April 2016, Prof. Davison.