My friend asked me to solve the problem of Cisco router DHCP configuration.

Some time ago, my colleague asked me a question about the DHCP configuration of the Cisco router. At that time, I did not give a positive answer, because this was my first time. In the following days, I have consulted relevant materials and are satisfied with the following answers. Share it with you now! In addition, most people do not know about the computer and do not operate these operations. Therefore, the customer asked us to allow any computer to access the LAN to access the Internet, so we had to configure DHCP 2600. 2600 router we identify as: Cisco enters global mode.

Cisco (config) # ip dhcp pool server "server" is the DHCP service Identification name, not a command
Cisco (dhcp-config) # network 192.168.1.0 255.255.255.0
Cisco (dhcp-config) # default-router 192.168.1.1
Cisco (dhcp-config) # dns-server 202.96.209.5 202.96.209.20.

At this point, the basic Cisco router DHCP function has been implemented, but there is another problem. If some computers in the LAN have already manually configured IP addresses, after other computers obtain the same IP address through DHCP and manually configure the computer to start up, it will cause an IP address conflict. It doesn't matter. The following steps can help us solve the problem and return to the global mode.

Cisco (config) # ip dhcp pool client0 "client0" is another Cisco router DHCP Service Identification name, so that the specific IP address can be mapped to a fixed MAC, Cisco (dhcp-config) # host 192.168.1.20 255.255.255.0, Cisco (dhcp-config) # client-identifier 0100. d0b7.1af8.4f note that "01" is not a MAC address and is used to mark the MAC as belonging to the LAN.

Note: The added client0 can only identify the MAC ing of one IP address to the MAC address. To identify multiple IP addresses mapped to the MAC address, you need to add multiple Cisco router DHCP service identification names, such as client1, client2, client3 .......) in the last problem, some IP addresses in the LAN may be allocated to fixed computers such as file servers. Therefore, you need to reserve these IP addresses. The solution is as follows: Cisco (config) # ip dhcp excluded-address 192.168.1.1 192.168.1.10 "1... 10 "The address between 192.168.1.1 and 192.168.1.10 will not be automatically allocated. This address segment can be set according to the actual situation.