Set the dce serial interfaces with clock rate step configure dynamic

Lab - Configuring Basic DHCPv4 on a Router (Instructor Version) Instructor Note: Red font color or gray highlights indicate text that appears in the instructor copy only.

Objectives
Part 1: Build the Network and Configure Basic Device Settings Part 2: Configure a DHCPv4 Server and a DHCP Relay Agent

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Note: This lab provides minimal assistance with the actual commands necessary to configure DHCP. However, the required commands are provided in Appendix A. Test your knowledge by trying to configure the devices without referring to the appendix.

Note: The routers used with CCNA hands-on labs are Cisco 1941 Integrated Services Routers (ISRs) with Cisco IOS Release 15.2(4)M3 (universalk9 image). The switches used are Cisco Catalyst 2960s with Cisco IOS Release 15.0(2) (lanbasek9 image). Other routers, switches and Cisco IOS versions can be used. Depending on the model and Cisco IOS version, the commands available and output produced might vary from what is shown in the labs. Refer to the Router Interface Summary Table at the end of this lab for the correct interface identifiers.

• 2 Switches (Cisco 2960 with Cisco IOS Release 15.0(2) lanbasek9 image or comparable)

• 2 PCs (Windows 7, Vista, or XP with terminal emulation program, such as Tera Term)

Step 1: Cable the network as shown in the topology.

Step 2: Initialize and reload the routers and switches.

service password-encryption

enable secret class

Lab - Configuring Basic DHCPv4 on a Router

password cisco

login

c. Configure the host name as shown in the topology.

R1(config)# router rip
R1(config-router)# version 2
R1(config-router)# network 192.168.0.0
R1(config-router)# network 192.168.1.0
R1(config-router)# network 192.168.2.252
R1(config-router)# no auto-summary

b. Configure RIPv2 and a default route to the ISP on R2.

Step 5: Verify network connectivity between the routers.

If any pings between routers fail, correct the errors before proceeding to the next step. Use show ip route and show ip interface brief to locate possible issues.

On R2, you will configure a DHCP address pool for each of the R1 LANs. Use the pool name R1G0 for the G0/0 LAN and R1G1 for the G0/1 LAN. You will also configure the addresses to be excluded from the address pools. Best practice dictates that excluded addresses be configured first, to guarantee that they are not accidentally leased to other devices.

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____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ ____________________________________________________________________________________ R2(config)# ip dhcp excluded-address 192.168.0.1 192.168.0.9
R2(config)# ip dhcp excluded-address 192.168.1.1 192.168.1.9
R2(config)# ip dhcp pool R1G1
R2(dhcp-config)# network 192.168.1.0 255.255.255.0
R2(dhcp-config)# default-router 192.168.1.1
R2(dhcp-config)# dns-server 209.165.200.225
R2(dhcp-config)# domain-name ccna-lab.com
R2(dhcp-config)# lease 2
R2(dhcp-config)# exit
R2(config)# ip dhcp pool R1G0
R2(dhcp-config)# network 192.168.0.0 255.255.255.0
R2(dhcp-config)# default-router 192.168.0.1
R2(dhcp-config)# dns-server 209.165.200.225
R2(dhcp-config)# domain-name ccna-lab.com
R2(dhcp-config)# lease 2
On PC-A or PC-B, open a command prompt and enter the ipconfig /all command. Did either of the host PCs receive an IP address from the DHCP server? Why?

____________________________________________________________________________________

Configure IP helper addresses on R1 to forward all DHCP requests to the R2 DHCP server.

On the lines below, write the commands necessary to configure R1 as a DHCP relay agent for the R1 LANs. _______________________________________________________________________________________ _______________________________________________________________________________________ _______________________________________________________________________________________ _______________________________________________________________________________________ R1(config)# interface g0/0
R1(config-if)# ip helper-address 192.168.2.254
R1(config-if)# exit
R1(config)# interface g0/1
R1(config-if)# ip helper-address 192.168.2.254

_______________________________________________________________________________________ PC-B: 192.168.0.10, and PC-A: 192.168.1.10

Step 4: Verify DHCP services and address leases on R2.

R2# show ip dhcp server statistics
Memory usage 42175

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How many types of DHCP messages are listed in the output?

____________________________________________________________________________________

Pool R1G0 :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Pending event : none
1 subnet is currently in the pool :
Current index IP address range Leased addresses 192.168.0.11 192.168.0.1 - 192.168.0.254 1

In the output of the show ip dhcp pool command, what does the current index refer to?

d. On R2, enter the show run | section dhcp command to view the DHCP configuration in the running configuration.

R2# show run | section dhcp
ip dhcp excluded-address 192.168.0.1 192.168.0.9 ip dhcp excluded-address 192.168.1.1 192.168.1.9 ip dhcp pool R1G1
network 192.168.1.0 255.255.255.0
default-router 192.168.1.1
domain-name ccna-lab.com
dns-server 209.165.200.225
lease 2
ip dhcp pool R1G0
network 192.168.0.0 255.255.255.0
default-router 192.168.0.1
domain-name ccna-lab.com
dns-server 209.165.200.225
lease 2

R1# show run interface g0/1
Building configuration...

Current configuration : 132 bytes
!

What do you think is the benefit of using DHCP relay agents instead of multiple routers acting as DHCP servers?

_______________________________________________________________________________________

Router Interface Summary Table

Router R1

R1(config)# interface g0/0

Router R2

R2(config)# ip dhcp excluded-address 192.168.0.1 192.168.0.9

Router R1

R1# show run
Building configuration...

enable secret 4 06YFDUHH61wAE/kLkDq9BGho1QM5EnRtoyr8cHAUg.2 !

no aaa new-model
!

Lab - Configuring Basic DHCPv4 on a Router

duplex auto
speed auto
!

router rip
version 2
network 192.168.0.0
network 192.168.1.0
network 192.168.2.252
!

ip forward-protocol nd
!

scheduler allocate 20000 1000

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R2# show run
Building configuration...

Current configuration : 1795 bytes
!

no aaa new-model
!

ip dhcp excluded-address 192.168.0.1 192.168.0.9 ip dhcp excluded-address 192.168.1.1 192.168.1.9 !

no ip domain lookup
ip cef
no ipv6 cef
multilink bundle-name authenticated
!

interface Embedded-Service-Engine0/0
no ip address

interface GigabitEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!

interface Serial0/0/0
ip address 192.168.2.254 255.255.255.252
!

no ip http server
no ip http secure-server
!

ip route 0.0.0.0 0.0.0.0 209.165.200.225
!

password cisco
login
transport input all
!

scheduler allocate 20000 1000
!

version 15.2
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!

hostname ISP
!

interface Embedded-Service-Engine0/0
no ip address
shutdown
!

interface GigabitEthernet0/0
no ip address
shutdown
duplex auto
speed auto
!

interface Serial0/0/0
no ip address
shutdown
clock rate 2000000
!

interface Serial0/0/1
ip address 209.165.200.225 255.255.255.224 !

line con 0
password cisco
logging synchronous
login
line aux 0
line 2
no activation-character
no exec
transport preferred none
transport input all
transport output pad telnet rlogin lapb-ta mop udptn v120 ssh stopbits 1
line vty 0 4
password cisco
login
transport input all
!

scheduler allocate 20000 1000
!