Note: Access points in a Load Group should be in the same general area of each other. Load information is shared between access points via IAPP Multicast. If IGMP snooping is used to prune off multicast traffic from a switch (no igmp querier present), Load Balance may not form properly.
- Select AP along the top of the Menu bar in the GUI of the controller.
- Select Load Groups down the left side.
- Select Client Balancing and click the New button at the bottom
- Give a name to your new group and click the Add button.
- Select the Radio Assignment tab and check the radio boxes of all the AP's you wish to add to this group.
- Select the WLAN Assignment tab and select all the WLAN Services you wish to load balance.
Green - The AP's formed properly
Red - The AP should be in the green group but because it's IAPP multicast packets were blocked, it's not in the group.
- Achieving a balanced system is accomplished by steering clients away from radios that are overloaded.
- Mechanism used to do this is through the responses to Probe, Authentication, and Association Requests.
- An AP radio can be in one of the following load states:
|Under-Loaded||Load <= Average|
|Balanced||Average < Load <=(Average + Margin)|
|Loaded||Load = (Average + Margin+1)|
|Over-Loaded||Load > (Average + Margin+1)|
Margin = Max( 3, or (10% of Average Load))
- The Load Balance State for any radio is based on the current load on that radio, and how this compares with the average load of all radios in the load group.
- The load for the radio is currently calculated as the number of clients associated.
- A client is considered to be roaming if it is associated with a member (AP radio) of the load group, and is probing or attempting to associate with another member of the same group.
- The AP always responds to, and accepts clients that are currently associated with that AP regardless of the load balance state.
- In a Under-Loaded State, an AP radio will respond to all Probe Requests, and accept associating clients that are new to the group or are roaming.
- In a Balanced State, an AP radio will not respond to probe requests from roaming clients, and will reject association requests from roaming clients by responding with a unsuccessful reason code of 17 (AP is unable to handle associated STA’s). It will only respond to probes and accept associations from clients new to the group.
- In an Loaded or Over-Loaded state, the AP does not respond to any Probe Request, and will reject all associations.
- Number of supported clients per Load Balance Group is 1024
- If this limit is reached, clients will still be allowed to Associate, but the load may not be optimally balanced.