CISCO 3550 vswitch DHCP configuration step 3

For details about how to configure DHCP for a CISCO 3550 switch, refer to some configuration content in this article for comparison and learning. After "ip helper-address dhcp server ADDRESS" according to the configuration described on the Internet, the project finds that the client cannot obtain the ip address from the DHCP server, I recently configured 3550 as a DHCP server relay proxy. I was also confused for a long time. Later, I searched for information online and asked for help from the forum. I finally passed the test in the project, in order to avoid such problems in the project, we need to adjust the configuration process left and right for your reference.

Network Environment: A 3550EMI switch is divided into three VLANs. vlan2 is the network where the server is located, named server, IP address segment is 192.168.2.0, subnet mask: 255.255.255.0, Gateway: 192.168.2.1, the Domain server is a windows 2000 advance server and also serves as a DHCP server. The DNS server has the IP address 192.168.2.10, vlan3 is the network where client 1 is located, the IP address segment is 192.168.3.0, The subnet mask is 255.255.255.0, And the Gateway: 192.168.3.1 is named work01, vlan4 is the network of client 2, work02, IP address segment is 192.168.4.0, subnet mask: 255.255.255.0, Gateway: 192.168.4.1.

3550 Ports 1-8 are allocated to VLAN 2, ports 9-16 are divided into VLAN 3, and ports 17-24 are allocated to VLAN 4.

To configure DHCP for a CISCO 3550 switch, follow these steps:

Step 1 of configuring DHCP for a CISCO 3550 vswitch: Create a VLAN:

Switch> Vlan Database

Switch (Vlan)> Vlan 2 Name server

Switch (Vlan)> Vlan 3 Name work01

Switch (vlan)> Vlan 4 Name work02

Step 2 of configuring DHCP for a CISCO 3550 switch: enable DHCP relay Proxy:

/* In the key step, if the following two commands are missing, use "ip helper-address dhcp server ADDRESS" in the VLAN to specify the DHCP server, and the client still cannot obtain the ip address */

Switch> Enable

Switch # Config t

Switch (Config) Service Dhcp

Switch (Config) Ip Dhcp Relay Information Option

Step 3 of configuring DHCP for a CISCO 3550 vswitch: Set the vlan ip Address:

Switch (Config)> Int Vlan 2

Switch (Config-vlan) Ip Address 192.168.2.1 255.255.255.0

Switch (Config-vlan) No Shut

Switch (Config-vlan)> Int Vlan 3

Switch (Config-vlan) Ip Address 192.168.3.1 255.255.255.0

Switch (Config-vlan) No Shut

Switch (Config-vlan)> Int Vlan 4

Switch (Config-vlan) Ip Address 192.168.4.1 255.255.255.0

Switch (Config-vlan) No Shut

Switch (Config-vlan) Exit

/* Note: Because the ports are not configured to VLAN2, 3, 4 at this time, each VLAN will be DOWN. After the ports are allocated to each VLAN, the VLAN will get up */