MicroNugget: How to Configure a Cisco Router as a DHCP Server

In this video, Jeremy Cioara covers how you can configure a Cisco router as a DHCP server. After explaining in brief what a DHCP server is and why a router is a better solution than a dedicated server, Jeremy explains not only how you can set this up on a Cisco router but also how you can test that it is properly working.

After watching this video, you will know exactly how to set up a DHCP server on a Cisco router. Jeremy does this by first explaining how you need to tell the router which IP addresses should be excluded from distribution.

He then shows you how to set up a DCHP pool and how you can configure a set of DNS servers through the router.

Finally, he describes how you can assign a range of addresses to the router, and he details the steps that you should take after all this is done to make certain that the router is now properly functioning as a DHCP server.

Start learning with CBT Nuggets:

[pavelejg]

This was so fast and so cool at the same time. Well explained. I love the part when the router says "I'm gonna help u buddy" hahah. Awesome

[mohmedhosny]

thank you very good but i wanna to know are the messages (discover, offer, request and ack ) still broadcast or change

[webnovice]

It'a quite simple. I created a small LAN network in my office and configured the DHCP on the router so it can assign ip addresses automatically to everything connected. You can also exclude range of address if you want them reserved for let's say printers or switches. Once you practice you'll get a hang of it.

[Arandolor]

"Now you're handing out IP addresses in less than five minutes " 🤣

[Protocol]

What would be the reasons why this would not work? I followed this exactly but when I check bindings, there is nothing listed. I don't think it matters but I issued no shut on all interfaces. Sh ip int br says nothing has IP except fot the static one he did to get things rolling.

[MajmeKriza]

At first I thought I wouldn't understand anything cause of your speed talking, but at the end ....I didn't get anything :p great tutorial man

[andybfmv]

This guy talks fast enough to be a car salesman

[ambidextrousproductions]

I know its probably very simple but how would you configure the interface going to the switch and from the switch to the router?

[Jallin]

So my question is, why choose fa 0/1 to give the switch an ip?

[Ben-xolp]

I feel bad for this guy, way too much coffee. What good is it to teach so fast? I would get anxiety listening to him for more than one Nugget. I would need CBD learning from CBT.

[NightBeyondVeil]

It doesnt work for me. I have a 1941 cisco router

[penttimuhli]

These days Windows Servers are quite stable, not very often that they crash. Nothing wrong with using a Windows Server for DHCP

[tombouwen]

BASISCONFIG:

HOSTNAME/MOTD
hostname <toestelnaam>
banner motd <bericht>
copy running-config startup-config
ip name-server serverip-1 serverip-2 (Hiermee kan je DNS instellen.)

IP/DNS:
ip address ip-address mask
ip default-gateway ip_address (hiermee stel je gateway in van B.V. switch naar router.)

VIRTUAL TERMINAL: (SSH/TELNET)
enable
configure terminal
line vty 0 15
transport input ssh
password cisco
login

ENABLE PASSWORD:
enable
config
configure terminal
enable password cisco
service password-encryption
crypto key generate rsa 1024


SWITCH 1
int fa0/1
sw mo trunk
vlan 100
name 100
vlan 200
name 200
int fa0/2
sw ac vl 100
int fa0/3
sw ac vl 200

SWITCH 0
int fa0/1
sw mo trunk
int fa0/2
sw mo trunk
vlan 100
name 100
vlan 200
name 200
int fa0/3
sw ac vl 100
int fa0/4
sw ac vl 200

ONGEDAAN MAKEN " NO sw ac vl 100 "

show interface trunk op switch = werkt trunk?
show vlan brief = vlans inzien met poorten

ROUTER 1:
int g0/1
no shut
int g0/1.100
encapsulation dot1q 100
ip add 10.100.0.1 255.255.255.0
int g0/1.200
encapsulation dot1q 200
ip add 10.200.0.1 255.255.255.0



Controle:
VLAN controleren - PC's naar elkaar pingen, BV. Vlan 100 naar 100 (zou moeten werken) en 100 naar 200 (zou niet moeten werken)
Kan ik vanaf VLAN 100, IP 10.100.0.1 pingen (Router/gateway).
VLAN 100 naar 200 ping zou via router moeten lopen.


DHCP config
Router1
VLAN 100 > DHCP
ip dhcp pool kubapool
network 10.100.0.0 255.255.255.0
default-router 10.100.0.1
dns-server 8.8.8.8 (default google DNS, check in de opdracht wat er gevraagd wordt)
domain-name kuba.pl

VLAN 200 > DHCP (EXACT HETZELFDE!)
ip dhcp pool kubapool
network 10.200.0.0 255.255.255.0
default-router 10.200.0.1
dns-server 8.8.8.8 (default google DNS, check in de opdracht wat er gevraagd wordt)
domain-name kuba.pl


Server 192.168.1.10
Pingen vanaf PC zou niet moeten werken.

Hoe in te stellen/troubleshooten:
show ip route = Route table
Controleer waar mijn netwerken zitten. (192.168.0.0 en 192.168.1.0)

Alle routers moeten alle netwekren ingesteld hebben / kennen.

Routes configureren:
ip route 192.168.1.0 255.255.255.0 192.168.0.2 (Volgende hop)
Doordat tweede router een ARP bericht krijgt weet hij dat hij naar de server toe moet.

ip route 10.100.0.0 255.255.255.0 192.168.0.1 (Volgende hop die verwijst naar VLAN netwerk)
ip route 10.200.0.0 255.255.255.0 192.168.0.1 (Volgende hop die verwijst naar VLAN netwerk)



HANDIG VOOR TROUBLESHOOTEN:
show interfaces
show interface status
show interfaces switchport
show interfaces trunk
show vlan brief

[tombouwen]

DHCP config
Router1
VLAN 100 > DHCP
ip dhcp pool kubapool
network 10.100.0.0 255.255.255.0
default-router 10.100.0.1
dns-server 8.8.8.8 (default google DNS, check in de opdracht wat er gevraagd wordt)
domain-name kuba.pl

VLAN 200 > DHCP (EXACT HETZELFDE!)
ip dhcp pool kubapool
network 10.200.0.0 255.255.255.0
default-router 10.200.0.1
dns-server 8.8.8.8 (default google DNS, check in de opdracht wat er gevraagd wordt)
domain-name kuba.pl