User's Guide

Figure 89: AP Fail Over When Connectivity to Primary Fails
The backup Extreme Campus Controller does not have to detect its link failure with the primary
Extreme Campus Controller for the session availability to kick in. If the AP loses five consecutive polls to
the primary Extreme Campus Controller either due to the Extreme Campus Controller outage or to
connectivity failure, it fails over to the backup Extreme Campus Controller fast enough to maintain the
user session.
In session availability mode (Figure 90), the APs connect to both the primary and backup Extreme
Campus Controller. While the connectivity to the primary Extreme Campus Controller is via the active
tunnel, the connectivity to the backup Extreme Campus Controller is via the backup tunnel.
Figure 90: Session Availability Mode
Availability
Administration
368 Extreme Campus Controller User Guide for version 5.46.03