Brocade Access Gateway Administrator's Guide - Supporting Fabric OS v5.2.1 (53-1000430-01)

Access Gateway Administrator’s Guide 1-7
Publication Number: 53-1000430-01
Failback policy
1
The ports mapped to N_2 (F_1, F_3, and F_4) failover 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 did not participate in the
failover event.
Figure 1-5 Example 1 and 2 failover policy behavior
Failback policy
The Brocade Access Gateway failback policy automatically reroutes the F_Ports back to the originally
mapped N_Ports as those N_Ports come back online.
Only the originally mapped F_Ports fail back. In the case of multiple N_Port failures, only F_Ports that
were mapped to the recovered N_Port experience failback. The remaining F_Ports are not redistributed
among the online N_Ports during the failback.
The following sequence describes how a failback event occurs:
1. When an N_Port comes back online, the F_Ports that were originally mapped to it are disabled.
2. The F_Port is reenabled on the original N_Port.
F_A2
Hosts
Access Gateway
Edge Switch
Fabric
(Switch_A)
enabled
NPIV
F_4
F_3
F_2
F_1
N_1
F_A1
enabled
NPIV
N_3
F_B1
enabled
NPIV
Host_1
Host_2
Host_3
Host_4
F_5
Host_5
F_6
Host_6
F_7
Host_7
F_8
Host_8
Edge Switch
(Switch_B)
N_4
F_B2
enabled
NPIV
N_2
Legend
Physical connection
Mapped online
Failover route online
Original mapped route
(offline)
Example 1
F_A2
Hosts
Access Gateway
Edge Switch
Fabric
(Switch_A)
enabled
NPIV
F_4
F_3
F_2
F_1
N_1
F_A1
enabled
NPIV
N_3
F_B1
enabled
NPIV
Host_1
Host_2
Host_3
Host_4
F_5
Host_5
F_6
Host_6
F_7
Host_7
F_8
Host_8
Edge Switch
(Switch_B)
N_4
F_B2
enabled
NPIV
Example 2
N_2
Note
The failback policy is an N_Port parameter. The failback policy is enabled by default.