1086 | Uplink Failure Detection (UFD)
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Figure 54-1.  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.
An enabled uplink-state group tracks the state of all assigned upstream interfaces. Failure on an upstream 
interface results in the automatic disabling of downstream interfaces in the uplink-state group. As a result, 
downstream devices can execute the protection or recovery procedures they have in place to establish 
alternate connectivity paths as shown in Figure 54-2. 
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