topic Re: PMK Roam Cache - What is defined as a neighboring APs? in Aerohive Migrated Content

PMK Roam Cache - What is defined as a neighboring APs?

simon_osullivan — Wed, 01 May 2019 12:08:24 GMT

Hi all,

The Aerohive documentation explains that:

With 802.1x authentication enabling PMK Roam cache is important. This enables the master key to be shared among neighboring APs to improve roaming.

My question is what defines a Neighbouring AP?

Do I need to select the neighboring AP's under the AP/optional configuration/roaming configuration?

Or are neighbour AP's set in some other method (dynamically)?

(I can't find anywhere in the documentation why Neighboring AP's should be configured, or what it does.)

Environment.....

Hivemanager classic 8.2r2

Mixutre of APs:

AP130 HiveOS 8.1r2

AP230 HiveOS 8.2r2

Re: PMK Roam Cache - What is defined as a neighboring APs?

samantha_lynn — Thu, 02 May 2019 02:59:46 GMT

These will be AMRP neighbors, so typically any APs within the same Hive. You can set Hive settings within the Network policy by going to Configure> Open the Network Policy in use> go to the Additional Settings tab> HIVE (Left hand side menu, under Policy Settings heading). Within the Hive Settings you can adjust what roaming information is shared with which AP. For instance we can set it up to share information with all APs in the same Hive that are within radio range, and/or to share information with all hive members in the same subnet.

Re: PMK Roam Cache - What is defined as a neighboring APs?

simon_osullivan — Thu, 02 May 2019 07:09:33 GMT

Thanks Sam,

Can you tell me when should I configure neighboring AP's under the AP/optional configuration/roaming configuration?

Re: PMK Roam Cache - What is defined as a neighboring APs?

samantha_lynn — Thu, 02 May 2019 16:54:10 GMT

It's not necessary for you to configure this manually, the Aerohive APs will automatically treat other APs in the same Hive as neighbors. You can fine tune which AP is selected as a neighbor in the settings I mentioned above, but that isn't necessary for roaming to work.

Re: PMK Roam Cache - What is defined as a neighboring APs?

AnonymousM — Thu, 02 May 2019 22:47:02 GMT

Sossie,

One scenario where you may want to edit those is very large deployments where all APs utilize the same Hive object. Especially if you're talking multiple campuses. There'd be no need for an AP at one campus to have that roaming information from a client at another campus. I can't imagine that it would a big enough deal to cause a problem (thinking RAM to store that cache), but I guess it could if we're talking hundreds of thousands of clients possibly.