User Manual

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3.6 Redundancy Overview (IGT-1205AT only)
The IGT-1205AT provides rapid ber redundancy of link for highly
critical Ethernet applications. The redundant-mode supports auto-
recover function. If the destination port of a packet is link down, it will
forward the packet to the other port of the backup pair. The following
gure shows the redundant function.
Main Primary
Backup
Redundancy
< Primary Port >
Link Status : Up
Traffic Flow : Forwarding
< Backup Port >
Link Status : Down
Traffic Flow : Blocking
Main Primary
Backup
Redundancy
< Primary Port >
Link Status : Down
Traffic Flow : N/A
< Backup Port >
Link Status : Up
Traffic Flow : Forwarding
Traffic is changed from Primary -Port to Backup-Port
Figure 3-3: Redundancy Behavior Topology
z Link status auto detect and redundant on dual ports with the same
connector type.
z Only when primary port is activated, the backup port is blocked.
z When primary port link failure occurs, the trafc will swap to backup
port automatically.
z Once the primary port status is back to link up, the trafc will swap
from backup port to primary port.