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Two DHCP pools 60 — Research and Legal on one router
Enterprise Intermediate 3 devices 5 checked tasks 100 points Plan lab
Scenario — the router in Puducherry has two LAN ports: Gi0/0 for Research (10.79.1.0/24) and Gi0/1 for Legal (10.79.2.0/24). Both groups use DHCP. Build one pool per LAN (RESEARCH and LEGAL), each handing out its own gateway and the DNS server 9.9.9.9, exclude the first ten addresses of both, then make both PCs lease and prove they reach each other through the router. You build it in a browser, type real commands at each device, and every task below is
checked against the running configuration — so you find out it is wrong before anybody else does.
Open this lab in the simulator
The simulator runs in your browser with nothing to install. This lab is part of the full simulator: open it free for 7 days with a new account, then with a plan. It needs an account, which keeps your progress.
The scenario
the router in Puducherry has two LAN ports: Gi0/0 for Research (10.79.1.0/24) and Gi0/1 for Legal (10.79.2.0/24). Both groups use DHCP. Build one pool per LAN (RESEARCH and LEGAL), each handing out its own gateway and the DNS server 9.9.9.9, exclude the first ten addresses of both, then make both PCs lease and prove they reach each other through the router.
Your role: a network engineer on the enterprise team. Level: Intermediate Done when: all 5 goals show as passed (100 points).
Network status
Devices: 1 router, 2 PCs, cabled as drawn. No Layer 1 or Layer 2 faults: every link is connected and up. R-Puducherry starts with addresses (G0/0 10.79.1.1/24, G0/1 10.79.2.1/24).
Known problems
None: nothing is misconfigured. The network is simply not finished: what the goals list is what you have to build or secure.
Goals
Pool RESEARCH serves 10.79.1.0/24 with gateway 10.79.1.1 (25 pts) Pool LEGAL serves 10.79.2.0/24 with gateway 10.79.2.1 (25 pts) The first ten addresses of both LANs are excluded (10 pts) Both PCs lease an address (20 pts) Research reaches Legal through the router (20 pts)
The activity, in order
Pool RESEARCH serves 10.79.1.0/24 with gateway 10.79.1.1 The configuration of R-Puducherry must contain the line: ip dhcp pool RESEARCH[\s\S]*network 10.79.1.0 255.255.255.0[\s\S]*default-router 10.79.1.1. Type it in the right mode (global, interface or line) and check it appears.Why: This is the task that checks your configuration directly: the line must really be there, not just look right. Verify with: show running-config Pool LEGAL serves 10.79.2.0/24 with gateway 10.79.2.1 The configuration of R-Puducherry must contain the line: ip dhcp pool LEGAL[\s\S]*network 10.79.2.0 255.255.255.0[\s\S]*default-router 10.79.2.1. Type it in the right mode (global, interface or line) and check it appears.Why: This is the task that checks your configuration directly: the line must really be there, not just look right. Verify with: show running-config The first ten addresses of both LANs are excluded The configuration of R-Puducherry must contain the line: ip dhcp excluded-address 10.79.1.1 10.79.1.10. Type it in the right mode (global, interface or line) and check it appears. The configuration of R-Puducherry must contain the line: ip dhcp excluded-address 10.79.2.1 10.79.2.10. Type it in the right mode (global, interface or line) and check it appears.Why: This is the task that checks your configuration directly: the line must really be there, not just look right. Verify with: show running-config Both PCs lease an address Research-PC must receive its address by DHCP (set its IP to DHCP, then check the lease). Legal-PC must receive its address by DHCP (set its IP to DHCP, then check the lease).Why: If the host has no address, look at the pool, the exclusions and, across a router, the ip helper-address. Verify with: ipconfig Research reaches Legal through the router From Research-PC, ping 10.79.2.11. If it fails, walk the path hop by hop: gateway, then each router’s routing table, then the way back.Why: A ping needs a route in BOTH directions. This is the end-to-end proof that everything before it worked. Verify with: ping 10.79.2.11
Tips
Work in the order given: later goals depend on the earlier ones. After every change, run the verify command before moving on; do not guess. Stuck? Read the verify output first. It names the interface, neighbour or route that is wrong. Common mistake: A pool whose network does not match any interface Common mistake: Reusing the same default-router in both pools Common mistake: Excluded range that is too small
Why this matters
One DHCP server can serve several subnets: the pool is chosen by the subnet of the interface the request came in on. Each pool needs its own network, gateway and exclusions.
What you will be able to do
Create several pools on one router
Match each pool to its interface subnet
Exclude infrastructure addresses
The network
ISR 2911, PC — 3 devices in all, already cabled.
Fa0 Gi0/0 10.79.1.1/24 Fa0 Gi0/1 10.79.2.1/24 R-Puducherry Research-PC Legal-PC Drawn from this lab: devices, cables, ports and the addresses already set.
Device Model Address already set
R-Puducherry ISR 2911 configure it
Research-PC PC configure it
Legal-PC PC configure it
Cabling
Research-PC Fa0 ↔ R-Puducherry Gi0/0
Legal-PC Fa0 ↔ R-Puducherry Gi0/1
What is configured at the start
These are already configured when the lab opens — including, where this is a troubleshooting lab, the fault itself:
R-Puducherry interface g0/0
ip address 10.79.1.1 255.255.255.0
no shutdown
exit
interface g0/1
ip address 10.79.2.1 255.255.255.0
no shutdown
exit
Tasks, and how each one is checked
Every task is decided by reading the live network — a neighbour in FULL, a ping that succeeds, a line in the running configuration — not by looking for a keyword you typed. The same command shows you what the lab sees.
# Task Pts How to verify it yourself
1 Pool RESEARCH serves 10.79.1.0/24 with gateway 10.79.1.1 25 On R-Puducherry: show running-config contains the line(s) matching ip dhcp pool RESEARCH\b[\s\S]*network 10\.79\.1\.0 255\.255\.255\.0[\s\S]*default-router 10\.79\.1\.1.
2 Pool LEGAL serves 10.79.2.0/24 with gateway 10.79.2.1 25 On R-Puducherry: show running-config contains the line(s) matching ip dhcp pool LEGAL\b[\s\S]*network 10\.79\.2\.0 255\.255\.255\.0[\s\S]*default-router 10\.79\.2\.1.
3 The first ten addresses of both LANs are excluded 10 On R-Puducherry: show running-config contains the line(s) matching ip dhcp excluded-address 10\.79\.1\.1 10\.79\.1\.10. and On R-Puducherry: show running-config contains the line(s) matching ip dhcp excluded-address 10\.79\.2\.1 10\.79\.2\.10.
4 Both PCs lease an address 20 On Research-PC: ipconfig shows an address. and On Legal-PC: ipconfig shows an address.
5 Research reaches Legal through the router 20 On Research-PC: ping 10.79.2.11 must succeed.
Stuck? Ask the coach
Tell the coach what you see or what you tried. It gives you a hint, not the answer, the way a senior engineer would. Included with a free trial or any plan.
Ask the coach
Common mistakes
A pool whose network does not match any interface
Reusing the same default-router in both pools
Excluded range that is too small
Reference solution
Try it yourself first — the lab checks your work either way. This is one configuration that makes every task pass, device by device:
R-Puducherry ip dhcp excluded-address 10.79.1.1 10.79.1.10
ip dhcp excluded-address 10.79.2.1 10.79.2.10
ip dhcp pool RESEARCH
network 10.79.1.0 255.255.255.0
default-router 10.79.1.1
dns-server 9.9.9.9
exit
ip dhcp pool LEGAL
network 10.79.2.0 255.255.255.0
default-router 10.79.2.1
dns-server 9.9.9.9
exit
Research-PC ipconfig /renew
Legal-PC ipconfig /renew
Where this is examined
CCNA 4.0 DHCP; Network+ 1.6.
This lab practises these topics in the zNetLaB certification courses:
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