DHCP Option 43 - BP

[Jay233]

Hi Everyone,

Quick question, I have an existing customer with 1142 lightweight access points using option 43 to provide controller IP addresses. I have proposed the 3500 series access points to increase an additional WLAN coverage requirement, can you confirm that the 3500’s will work on the same DHCP scope as the existing 1142’s if I create and include the correct Vendor Class for the 3500’s (Cisco AP c3500).  

What would be best practice for multiple AP types utilizing option 43 on the same DHCP scope?

I keep reading in Cisco documents that you should have multiple DHCP scopes per AP type? Is this recommendation due to using option 60 in conjunction with option 43?

Has anyone used option 82 in conjunction with Cisco AP's and a Microsoft DHCP.

As always a big thank you in advance. 

[George Stefanick · Accepted solution]

Quick question, I have an existing customer with 1142 lightweight access points using option 43 to provide controller IP addresses. I have proposed the 3500 series access points to increase an additional WLAN coverage requirement, can you confirm that the 3500’s will work on the same DHCP scope as the existing 1142’s if I create and include the correct Vendor Class for the 3500’s (Cisco AP c3500).   
What would be best practice for multiple AP types utilizing option 43 on the same DHCP scope? 
I keep reading in Cisco documents that you should have multiple DHCP scopes per AP type? Is this recommendation due to using option 60 in conjunction with option 43?
Has anyone used option 82 in conjunction with Cisco AP's and a Microsoft DHCP.
As always a big thank you in advance.  

Jason the anwser to your question depends on what you use for DHCP. If you use a MS server, then you wont have any issue.

You can simply add the additonal VCI and then add it to the scope. Works like a charm.

If you use a cisco router or switch for DHCP and your are doing VCI / OPTION 43, then you will be locked 1 per ap.

I did a number of post on DHCP option 43 ..

See these for reference

http://www.my80211.com/home/2012/3/3/cisco-ap-vci-60-serviceprovider.html

http://www.my80211.com/cisco-wlc-labs/2009/7/4/cisco-dhcp-option-43-configuration-nugget.html

Enjoy

[blakekrone · Accepted solution]

George is spot on, if you are using Microsoft DHCP then you can have as many VCI's and Option 43's setup on a scope as you want.

However, when doing this on Cisco IOS DHCP it's a little bit trickier and requires you to limit yourself to 1 AP type per scope.

[Scott Fella · Accepted solution]

Just to add, if you plan on add 3500's to an existing wireless environment on the same WLC's, then you don't need to even specify a VCI's on the dhcp scope. You would only need to do that if your putting AP's on the same subnet but on different WLC's.

Thanks,

Scott Fella

Sent from my iPhone

[Jay233]

Guy’s

Really appreciate the speedy responses.

Cheers,

George,

Had already reviewed your POST’s on option 43 along with some stuff on Jerome’s Blog, have been a big fan of your web site for some time.

Scott,

Exactly my thoughts only needed to segment access points based on model type when utilizing the same subnet but with a requirement to join specific/different controller IP address.