You can use DHCP Option 43 to provide a list of controller IP addresses to the access points, enabling them to find and join a
controller. For additional information, refer to
Configuring DHCP Option 43 and DHCP Option 60, on page 58
.
Configuring DHCP Option 43 and DHCP Option 60
This section contains a DHCP Option 43 configuration example on a Windows 2003 Enterprise DHCP server for use with Cisco
wireless access points. For other DHCP server implementations, consult the product documentation for configuring DHCP Option
43.
With DHCP Option 43, use the IP address of the controller management interface.
•
DHCP Option 43 is limited to one access point type per
DHCP pool. You must configure a separate DHCP pool
for each access point type.
•
DHCP servers must be programmed to return the option
based on the DHCP Vendor Class Identifier (VCI) string
of the access point (DHCP Option 60). The VCI string
for the access point is:
Cisco AP iw370s
If you ordered an access point with the Service Provider Option
(AIR-OPT60-DHCP) selected in the ordering tool, the VCI
string for the access point contains
-ServiceProvider
. For
example, an access point with this option returns this VCI
string:
Cisco AP iw3702-ServiceProvider
Notes:
The Cisco IW3702 access point uses the type-length-value (TLV) format for DHCP Option 43. The TLV block format is:
•
Type: 0xf1 (decimal 241)
•
Length: Number of controller IP addresses * 4
•
Value: List of Cisco Wireless LAN Controller management interfaces
To configure DHCP Option 43 in the embedded Cisco IOS DHCP server:
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.
Example DHCP scope commands:
Example:
ip dhcp pool pool_name
network IP_network netmask
default-router default_router
dns-server DNS_Server
where,
58
