Dell S4048T - How Uplink Failure Detection Works

• In Step C, UFD on S1 disables the link to the server. The server then stops using the link to S1 and
switches to using its link to S2 to send traffic upstream to R1.
Figure 134. Uplink Failure Detection
How Uplink Failure Detection Works
UFD creates an association between upstream and downstream interfaces. The association of uplink and
downlink interfaces is called an uplink-state group.
An interface in an uplink-state group can be a physical interface or a port-channel (LAG) aggregation of
physical interfaces.
Uplink Failure Detection (UFD) 1089