Settings of cisco dhcp client and server

In some vro configurations, DHCP is usually used. So today we will explain some settings in this regard. Let's take a look at the settings of cisco dhcp client and Service. DHCP defines in rf12001 that UDP is used for datagram transmission and port 67,68 is used.

After Cisco IOS 12.0 T1, it can be configured as DHCP relay, cisco DHCP Client, and DHCP Service.

DHCP Relay configuration

Router # conf t

Enter configuration commands, one per line. End with CNTL/Z.

Router (config) # int fa0/0

Router (config-if) # ip helper-address 10.1.1.1 specify the IP address of the DHCP server

In fact, the ip helper-address command not only forwards DHCP request packets, but also forwards other UDP packets by default, such as DNS requests, and forwards all the Server IP addresses defined by it, this will undoubtedly increase the server load and cause network problems. You can use the following command to disable meaningless UDP broadcast forwarding:

Router (config) # no ip forward-protocol udp?

DHCP Client configuration

Router # conf t

Enter configuration commands, one per line. End with CNTL/Z.

Router (config) # int fa0/0

Router (config-if) # ip address dhcp client-id fa0/0 enable the DHCP Client and get the IP too much from the fa0/0 interface (it is not recommended to configure the Router as a cisco DHCP client, it is generally used when a vro connects to the ISP as a network boundary)

DHCP Server configuration

Router # conf t

Enter configuration commands, one per line. End with CNTL/Z.

Router (config) # enable dhcp in service DHCP

Router (config-if) # ip dhcp pool 10.1.1.0/24 defines DHCP pool

Router (config-if) # network 10.1.1.0 255.255.255.0 defines the address range

Router (config-if) # default-router 10.1.1.1 defines the default Gateway

Router (config-if) # exit

Router (config) # ip dhcp excluded-address 10.1.1.100 10.1.1.150 defines the excluded ip address range

Router (config-if) # end

At this point, we have resolved all the settings of the cisco DHCP Client and Service.