In one installation we have a pair of C5210 in HA mode with fast failover enabled.
The network of registration of APs is 10.90.x.x in esa1 and the network HA is 1.1.1.x directly connected by esa3.
We note that in the configuration of APs these four interfaces appear as failover addresses:
And in the capture of the packets we noticed that there is an attempt to ping the four interfaces and, of course, without success in the interfaces of HA 1.1.1.x. And this occurs every 1 second.
Here's the questions: would these network configurations be incompatible with HA FastFailover and why do APs test connectivity with esa3?