Network and System Administration (BSc CSIT, CSC412): the questions likely to come
80 analyzed questions from 7 past papers (2074-2081), grouped by syllabus unit — each with its probability, how often it's been asked, and where to study the answer.
Explain DNS and DHCP. Compare their roles, describe their configuration, and discuss how they work together in a network.
DNS and DHCP
DNS (Domain Name System)
DNS is a hierarchical, distributed naming system that resolves human-readable domain names into IP addresses (and vice versa). When a host needs to reach www.example.com, its resolver queries DNS servers (root → TLD → authoritative) to obtain the corresponding IP (e.g. 93.184.216.34). It uses UDP/TCP port 53.
Configuration (Linux/BIND example): zone files declare records such as A, AAAA, CNAME, MX, NS, PTR.
; example.com zone file
@ IN SOA ns1.example.com. admin.example.com. ( 2024010101 3600 900 604800 86400 )
@ IN NS ns1.example.com.
www IN A 192.168.1.10
mail IN MX 10 mail.example.com.
Clients point to a resolver via /etc/resolv.conf (nameserver 8.8.8.8).
DHCP (Dynamic Host Configuration Protocol)
DHCP automatically assigns IP configuration to clients — IP address, subnet mask, default gateway, and DNS server addresses — eliminating manual setup. It uses UDP ports 67 (server) and 68 (client) and works through the DORA exchange: Discover → Offer → Request → Acknowledge.
Configuration (ISC dhcpd example):
subnet 192.168.1.0 netmask 255.255.255.0 {
range 192.168.1.100 192.168.1.200;
option routers 192.168.1.1;
option domain-name-servers 192.168.1.10;
default-lease-time 600;
}
Comparison of Roles
| Aspect | DNS | DHCP |
|---|---|---|
| Purpose | Name ↔ IP resolution | Assign IP configuration |
| Port | 53 (UDP/TCP) | 67/68 (UDP) |
| Output | IP address for a name | IP, mask, gateway, DNS |
| State | Mostly static records | Dynamic leases |
How They Work Together
When a host joins a network, DHCP first leases it an IP address, subnet mask, gateway, and the address of the DNS server to use. The client then uses that DNS server to resolve names into IP addresses for actual communication. Modern setups also use Dynamic DNS (DDNS): the DHCP server updates DNS records automatically when it hands out a lease, so a client's hostname always maps to its current IP. Thus DHCP handles who am I / how do I connect, and DNS handles where is the host I want to reach.
Network Administration and Services
Explain DNS and DHCP. Compare their roles, describe their configuration, and discuss how they work together in a network.
What is a web server? Explain the architecture of Apache/Nginx, virtual hosting, and HTTPS configuration using SSL/TLS.
What is the Domain Name System? Explain forward and reverse lookup zones and configure a caching-only DNS server.
Explain DHCP in detail. Describe the DHCP message exchange (DORA process) and the steps to configure a DHCP server.
Explain TCP/IP configuration and troubleshooting. Discuss the common network troubleshooting tools (ping, traceroute, netstat, nslookup).
What is a mail server? Explain the working of SMTP, POP3, and IMAP and the steps to configure a mail server.
Explain the process of installing and configuring a web server (Apache). Discuss virtual hosting and access control.
What is the difference between a switch and a router?
What is a reverse proxy?
Explain the Domain Name System (DNS). Describe the DNS hierarchy, types of DNS records, and the steps to configure a DNS server.
What is the function of /etc/resolv.conf?
What is port forwarding?
Write short notes on network monitoring protocols.
Explain DHCP relay agent.
Differentiate between static and dynamic routing.
Explain the structure of a DNS zone file.
What is a load balancer?
What is DNS resolution? Explain recursive and iterative queries.
Explain the DHCP lease process.
Write short notes on network address translation (NAT).
Differentiate between TCP and UDP.
What is SNMP? Explain its use in network management.
What is a proxy server?
What is DHCP? Explain how it assigns IP addresses dynamically.
Sit a probable paper
A full mock exam built from the most likely questions, mirroring the real paper's structure. Every slot is a real past question.
Most Probable Paper
Mirrors the real structure · 60 marks · based on 7 past papers
- 1.[10 marks]
Explain network security in detail. Discuss firewalls, VPNs, encryption, and best practices for securing servers and services.
This question has recurred in 3 of 7 years; so far only in internal assessments, not the board; and its topic (System and Network Security) appears in 86% of years.
- 2.[10 marks]
Explain DNS and DHCP. Compare their roles, describe their configuration, and discuss how they work together in a network.
Asked once (2081); so far only in internal assessments, not the board; and its topic (Network Administration and Services) appears in 100% of years.
- 3.[10 marks]
What is a web server? Explain the architecture of Apache/Nginx, virtual hosting, and HTTPS configuration using SSL/TLS.
Asked once (2080); so far only in internal assessments, not the board; and its topic (Network Administration and Services) appears in 100% of years.
- 1.[5 marks]
Explain the role of the crontab file.
This question has recurred in 2 of 7 years; so far only in internal assessments, not the board; and its topic (Maintaining and Monitoring System Processes and Performance) appears in 86% of years.
- 2.[5 marks]
Explain the LDAP authentication process.
This question has recurred in 2 of 7 years; so far only in internal assessments, not the board; and its topic recurs in 5 of 7 years.
- 3.[5 marks]
What is the difference between a switch and a router?
Asked once (2081); so far only in internal assessments, not the board; and its topic (Network Administration and Services) appears in 100% of years.
- 4.[5 marks]
What is a reverse proxy?
Asked once (2081); so far only in internal assessments, not the board; and its topic (Network Administration and Services) appears in 100% of years.
- 5.[5 marks]
What is the function of /etc/resolv.conf?
Asked once (2080); so far only in internal assessments, not the board; and its topic (Network Administration and Services) appears in 100% of years.
- 6.[5 marks]
What is port forwarding?
Asked once (2080); so far only in internal assessments, not the board; and its topic (Network Administration and Services) appears in 100% of years.
- 7.[5 marks]
Write short notes on network monitoring protocols.
Asked once (2080); so far only in internal assessments, not the board; and its topic (Network Administration and Services) appears in 100% of years.
- 8.[5 marks]
Explain DHCP relay agent.
Asked once (2079); so far only in internal assessments, not the board; and its topic (Network Administration and Services) appears in 100% of years.
- 9.[5 marks]
Differentiate between static and dynamic routing.
Asked once (2079); so far only in internal assessments, not the board; and its topic (Network Administration and Services) appears in 100% of years.
Behind the numbers
The raw evidence the predictions are computed from: marks per unit per year, syllabus weights, trends, and coverage.
Show the heatmap, topic table and coverage analysis
The receipt: marks per unit, per year
Each row is a syllabus unit, each column an exam year, each cell the marks that unit earned that year. Click any cell to see the actual questions behind it.
| # | Syllabus unit | Probability | Appeared | Avg marks | Syllabus weight | Exam vs syllabus | Trend | Questions |
|---|---|---|---|---|---|---|---|---|
| 1 | U7Network Administration and Services | Very likely100% | 22.9 | 16%7 lecture hrs | Over-examinedexam 30% · syllabus 16% | Steady | none repeat24 total | |
| 2 | U4Managing File Systems and Storage | Very likely100% | 11.4 | 13%6 lecture hrs | Balancedexam 15% · syllabus 13% | Steady | none repeat15 total | |
| 3 | U8System and Network Security | Very likely86% | 13.3 | 11%5 lecture hrs | Balancedexam 15% · syllabus 11% | Steady | 1 recurring11 total | |
| 4 | U6Maintaining and Monitoring System Processes and Performance | Very likely86% | 11.7 | 11%5 lecture hrs | Balancedexam 13% · syllabus 11% | Steady | 1 recurring11 total | |
| 5 | U3Managing Users and Groups | Likely71% | 8 | 13%6 lecture hrs | Balancedexam 8% · syllabus 13% | Steady | 1 recurring5 total | |
| 6 | U1Introduction to System Administration | Likely57% | 10 | 11%5 lecture hrs | Balancedexam 8% · syllabus 11% | Steady | none repeat5 total | |
| 7 | U2Setting up a System | Likely71% | 6 | 13%6 lecture hrs | Under-examinedexam 6% · syllabus 13% | Steady | none repeat6 total | |
| 8 | U5Backups and System Recovery | Possible43% | 8.3 | 11%5 lecture hrs | Under-examinedexam 5% · syllabus 11% | Steady | none repeat3 total |
Study smart, not hard
Drag the slider: studying the top 5 units in priority order covers ~82% of all observed marks.
- ~80% line
Lecture time vs exam marks
Where the exam pays more than the curriculum spends: ● lectures vs ● exam marks, as a share of the whole course. A long teal-leading bar = high-yield unit.