N_Port goes offline. This occurs regardless of whether the Failover policy is enabled or disabled for
the primary N_Port.
Failover with port mapping
The Failover policy allows F_Ports to automatically remap to an online N_Port if the primary N_Port
goes offline. If multiple N_Ports are available for failover, the Failover policy evenly distributes the
F_Ports to available N_Ports belonging to the same N_Port group. If no other N_Port is available,
failover does not occur and the F_Ports mapped to the primary N_Port go offline as well.
AG provides an option to specify a secondary failover N_Port for an F_Port.
NOTE
If failover and failback policy are disabled, an F_Port mapped to an N_Port will go offline when the
N_Port goes offline and it will go online when the N_Port comes online.

Failover configurations in Access Gateway

The following sequence describes how a failover event occurs:
• An N_Port goes offline.
• All F_Ports mapped to that N_Port are temporarily disabled.
• If the Failover policy is enabled on an offline N_Port, the F_Ports mapped to it will be distributed
among available online N_Ports. If a secondary N_Port is defined for any of these F_Ports, these
F_Ports will be mapped to those N_Ports. If the Port Grouping policy is enabled, then the F_Ports
only fail over to N_Ports that belong to the same port group as the originally offline N_Port.

Failover example

The following example shows the failover sequence of events in a scenario where two fabric ports go
offline, one after the other. Note that this example assumes that no preferred secondary N_Port is set
for any of the F_Ports.
• First, the Edge switch F_A1 port goes offline, as shown in Example 1 below, causing the
corresponding Access Gateway N_1 port to be disabled.
The ports mapped to N_1 fail over; F_1 fails over to N_2 and F_2 fails over to N_3.
• Next, the F_A2 port goes offline, as shown in Example 2 below, causing the corresponding Access
Gateway N_2 port to be disabled.
The ports mapped to N_2 (F_1, F_3, and F_4) fail over to N_3 and N_4. Note that the F_Ports are
evenly distributed to the remaining online N_Ports and that the F_2 port did not participate in the
failover event.

Failover with port mapping

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