Configuring Option 43 in DHCP

Here is the basic procedure for configuring option 43:

1. On the DHCP console find the scope on which you need to configure the option

2. Under the scope select the scope option and right click the scope option and select the configure options

3. In the scope options dialogue box, scroll down and select 043 vendor specific info

4. In the data entry field, click any where under the ASCII heading and enter the following information

ASCII : Loopback address of the master (This address may be one of three things:

the loopback address of the master, the virtual IP (VIP) address of a VRRP group for the master, or the IP address of the terminating local Controller)

5. Click the OK to save the configuration

DHCP Option 43

DHCP servers are a popular way of configuring clients with basic networking information such as an IP address, a default gateway, network mask, DNS server, etc. Most DHCP servers have the ability to

also send a variety of optional information as well. One of these is the Vendor-Specific Option Code, often called option 43.

Here is how option 43 works:

1 The DHCP client on an Aruba AP adds an optional piece of information called the Vendor Class Identifier Code (Option 60) to its DHCP request. The value of this code is ArubaAP

2 The DHCP server sees the vendor information and checks if it has option 43 configured, if it does, it will send the Vendor-Specific Option Code (43) to the client. The value of this option is the loopback address of the Aruba master

3 The AP gets a response from the DHCP server and checks if option 43 was returned, if it was, the AP contacts the master using the supplied IP address

option 43 will return the Aruba master IP address to an Aruba DHCP client. This information allows Aruba APs to auto-discover their master and gain their configuration.