How the E2122 HA works when one unit fail ?

[AndréP]

Does a pair of E2122 continue to support 32000 sessions if one of the two devices stops working (breaks down) ?

[Paulo_Francisco]

Yes. Each controller is engineered to be able to withstand the full capacity of the High-availability pair (APs and end-user sessions) in a Failover event situation.

[Jayden69]

I appreciate the information and advice you have shared. I will try to figure it out for more.
DMVNow

[Paulo_Francisco]

Hi Andre,
Yes. In an High Availability setup, while AP balancing may be distributed based on HA mode (Active-Active, Active-Passive, Site-Assigned) each controller is engineered to be resilient to the whole capacity of the pair. I.e In the case of Failover event (Controller shutdown/upgrade for example), the peer controller will support the entire capacity of the pair. In the case of a pair of E2122, the 'surviving' member would indeed support up to 4000 APs and 32,000 end-user sessions.