Understanding N+M in HA Mode

The M of N+M is a fixed number representing the reserve spare capacity Avi Load Balancer strives to maintain across the Service Engine (SE) group on an ongoing basis, a capacity total that is equivalent to M empty SEs.

The N of N+M is the minimum number of SEs required to place virtual services in the SE group. It is calculated by the Avi Load Balancer Controller based on the Virtual Services per Service Engine parameter. N will vary over time, as virtual services are placed on or removed from the group. N+M is one of the high availability modes available on Avi Load Balancer.