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Two DHCP pools 03 — HR and Guests on one router
Enterprise Intermediate 3 devices 5 checked tasks 100 points Plan lab
Scenario — the router in Mumbai has two LAN ports: Gi0/0 for HR (10.22.1.0/24) and Gi0/1 for Guests (10.22.2.0/24). Both groups use DHCP. Build one pool per LAN (HR and GUESTS), 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.
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The scenario
the router in Mumbai has two LAN ports: Gi0/0 for HR (10.22.1.0/24) and Gi0/1 for Guests (10.22.2.0/24). Both groups use DHCP. Build one pool per LAN (HR and GUESTS), 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-Mumbai starts with addresses (G0/0 10.22.1.1/24, G0/1 10.22.2.1/24). 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 HR serves 10.22.1.0/24 with gateway 10.22.1.1 (25 pts) Pool GUESTS serves 10.22.2.0/24 with gateway 10.22.2.1 (25 pts) The first ten addresses of both LANs are excluded (10 pts) Both PCs lease an address (20 pts) HR reaches Guests through the router (20 pts) The activity, in order
Pool HR serves 10.22.1.0/24 with gateway 10.22.1.1 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 GUESTS serves 10.22.2.0/24 with gateway 10.22.2.1 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 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 Why: If the host has no address, look at the pool, the exclusions and, across a router, the ip helper-address. Verify with: ipconfig HR reaches Guests through the router Why: A ping needs a route in BOTH directions. This is the end-to-end proof that everything before it worked. Verify with: ping 10.22.2.11 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 10.22.1.1/24 Fa0 Gi0/1 10.22.2.1/24 R-Mumbai HR-PC Guests-PC Drawn from this lab: devices, cables, ports and the addresses already set. Device Model Address already set
R-Mumbai ISR 2911 configure it HR-PC PC configure it Guests-PC PC configure it
Cabling
HR-PC Fa0 ↔ R-Mumbai Gi0/0 Guests-PC Fa0 ↔ R-Mumbai 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-Mumbai interface g0/0
ip address 10.22.1.1 255.255.255.0
no shutdown
exit
interface g0/1
ip address 10.22.2.1 255.255.255.0
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 HR serves 10.22.1.0/24 with gateway 10.22.1.1 25 On R-Mumbai: show running-config contains the line(s) matching ip dhcp pool HR\b[\s\S]*network 10\.22\.1\.0 255\.255\.255\.0[\s\S]*default-router 10\.22\.1\.1. 2 Pool GUESTS serves 10.22.2.0/24 with gateway 10.22.2.1 25 On R-Mumbai: show running-config contains the line(s) matching ip dhcp pool GUESTS\b[\s\S]*network 10\.22\.2\.0 255\.255\.255\.0[\s\S]*default-router 10\.22\.2\.1. 3 The first ten addresses of both LANs are excluded 10 On R-Mumbai: show running-config contains the line(s) matching ip dhcp excluded-address 10\.22\.1\.1 10\.22\.1\.10. and On R-Mumbai: show running-config contains the line(s) matching ip dhcp excluded-address 10\.22\.2\.1 10\.22\.2\.10. 4 Both PCs lease an address 20 On HR-PC: ipconfig shows an address. and On Guests-PC: ipconfig shows an address. 5 HR reaches Guests through the router 20 On HR-PC: ping 10.22.2.11 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-Mumbai ip dhcp excluded-address 10.22.1.1 10.22.1.10
ip dhcp excluded-address 10.22.2.1 10.22.2.10
ip dhcp pool HR
network 10.22.1.0 255.255.255.0
default-router 10.22.1.1
dns-server 9.9.9.9
exit
ip dhcp pool GUESTS
network 10.22.2.0 255.255.255.0
default-router 10.22.2.1
dns-server 9.9.9.9
exit HR-PC ipconfig /renew Guests-PC ipconfig /renew Where this is examined
CCNA 4.0 DHCP; Network+ 1.6.
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