Cisco Catalyst 9136I Series Hardware Installation Manual page 36

Configuring DHCP Option 43
To configure DHCP Option 43 in the embedded Cisco IOS DHCP server, follow these steps:
Procedure
Step 1 Enter configuration mode at the Cisco IOS CLI.
Step 2
Create the DHCP pool, including the necessary parameters such as default router and name server. A DHCP
scope example is as follows:
Example:
ip dhcp pool <pool name>
network <IP Network> <Netmask>
default-router <Default router>
dns-server <DNS Server>
Here:
Example:
<pool name>: is the name of the DHCP pool, such as AP9136I
<IP Network>: is the network IP address where the controller resides, such as 10.0.15.1
<Netmask>: is the subnet mask, such as 255.255.255.0
<Default router>: is the IP address of the default router, such as 10.0.0.1
<DNS Server>: is the IP address of the DNS server, such as 10.0.10.2
Step 3
Add the Option 43 line using the following syntax:
Example:
option 43 hex <hex string>
The hex string is assembled by concatenating the following TLV values:
Type + Length + Value
For example, if there are two controllers with management interface IP addresses, 10.126.126.2 and
10.127.127.2, the type is f1(hex), the length is 2 * 4 = 8 = 08 (hex), and the IP addresses translate to 0a7e7e02
and 0a7f7f02. Assembling the string then yields f1080a7e7e020a7f7f02. The resulting Cisco IOS command
added to the DHCP scope is option 43 hex f1080a7e7e020a7f7f02.
Cisco Catalyst 9136I Series Access Point Hardware Installation Guide
28
Troubleshooting