Layer 3 switch of Cisco Packet Tracer interrupts DHCP
Experimental environment:
Experimental purpose:
1. Divide the VLAN into vlan10\ vlan100\ vlan200 and specify IP as 192.168.10.254\ 192.168.100.254\ 192.168.200.254 respectively.
2. Divide fa0/1\ fa02\ fa04 into VLAN100\ VLAN 200\ VLAN10.
3. Enable the routing protocol in the layer 3 switch so that the VLAN can communicate with each other. (if only to obtain the IP address, not to use a routing protocol)
4. Enable ip helper-address for each VLAN on the layer 3 switch.
5. Add an IP address pool on the server.
6. Check whether PC can obtain the IP address normally.
1. Divide the VLAN into vlan10\ vlan100\ vlan200 and specify IP as 192.168.10.254\ 192.168.100.254\ 192.168.200.254 respectively.
Switch#conf t
Enter configuration commands, one per line. End with CNTL/Z.
Switch (config) # vlan 10
Switch (config-vlan) # exit
Switch (config) # vlan 100
Switch (config-vlan) # exit
Switch (config) # vlan 200
Switch (config-vlan) # exit
Switch (config) # int vlan 10
Switch (config-if) #
% LINK-5-CHANGED: Interface Vlan10, changed state to up
Switch (config-if) # ip add 192.168.10.254 255.255.255.0
Switch (config-if) # no shutdown
Switch (config-if) # exit
Switch (config) # int vlan 100
Switch (config-if) #
% LINK-5-CHANGED: Interface Vlan100, changed state to up
Switch (config-if) # ip add 192.168.100.254 255.255.255.0
Switch (config-if) # no shutdown
Switch (config-if) # exit
Switch (config) # int vlan 200
Switch (config-if) #
% LINK-5-CHANGED: Interface Vlan200, changed state to up
Switch (config-if) # ip add 192.168.200.254 255.255.255.0
Switch (config-if) # no shutdown
2. Divide fa0/1\ fa02\ fa04 into VLAN100\ VLAN 200\ VLAN10.
Switch (config) # int fa0/1
Switch (config-if) # switchport mode access
Switch (config-if) # switchport access vlan 100
Switch (config-if) #
% LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan100, changed state to up
Switch (config-if) # exit
Switch (config) # int fa0/2
Switch (config-if) # switchport mode access
Switch (config-if) # switchport access vlan 200
Switch (config-if) #
% LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan200, changed state to up
Switch (config-if) # exit
Switch (config) # int fa0/4
Switch (config-if) # switchport mode access
Switch (config-if) # switchport access vlan 10
3. Enable the routing protocol in the layer 3 switch so that the VLAN can communicate with each other.
Switch (config) # ip routing
4. Enable ip helper-address for each VLAN on the layer 3 switch.
Switch (config) # int vlan 10
Switch (config-if) # ip helper-address 192.168.10.1 (DHCP server IP)
Switch (config-if) # exit
Switch (config) # int vlan 100
Switch (config-if) # ip helper-address 192.168.10.1
Switch (config-if) # exit
Switch (config) # int vlan 200
Switch (config-if) # ip helper-address 192.168.10.1
Switch (config-if) # exit
5. Add an IP address pool on the server.
6. Check whether PC can obtain the IP address normally, as follows:
