Configure Cisco WLC 2100 + AP's to work with Sonicwall 4500 DHCP option 43

I inherited a couple dozen Cisco Aironet 1130 AG Series access points and two Cisco 2100 Wireless Lan Controllers.   I want to configure the WLC and access points to work with a Sonicwall 4500.    The problem I'm running into, is that the Sonicwall's DHCP option 43 is limited to "one byte data" fields.  And, from my understanding, the Cisco AP's receive the IP location of the WLC's from the Option 43 settings with a DHCP lease.  The AP's seem to require receiving the Option 43 information in hex format.     Has anyone configured a cisco WLC using the DHCP server with a Sonicwall?   If so, how did you convert the IP of the WLC into "one byte data"?     I am willing to pay for help from a Cisco expert that can get the AP's to associate with the WLC using a Sonicwall 4500.
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Craig BeckCommented:
If you can put the Cisco APs on the same VLAN as the Cisco WLC management interface you don't need DHCP to give Option 43 to the APs.

The AP will do a subnet broadcast once it receives an IP address to see if there is a WLC on the same subnet.  If no response is received from a WLC it will use the IP address given from DHCP, or it will use DNS to resolve the IP of host CISCO-LWAPP-CONTROLLER or CISCO-CAPWAP-CONTROLLER (depending on AP/WLC software version) to find the IP address of the WLC.

Don't quote me but to configure Option 43 on the sonicwall is a little complicated.  You need to enable the 'option-array' option to allow you to add HEX values, then convert the IP of the WLC to HEX, add the type and length values to the string, and the option number, in the format:


So, if your WLC IP address is you'd enter the following into the 'Option Value' box...


The TYPE is ALWAYS 0xF1.  The LENGTH is the number of WLC IP addresses in the option multiplied by 4 (hence 0x04), so if you had 2 WLCs you would use 0xF1;0x08.

You'll find plenty of IP to HEX converters on the web.

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