Deployment Guide
Figure 34. Uplink Failure Detection Example
If only one of the upstream interfaces in an uplink-state group goes down, a specied number of downstream ports associated with the
upstream interface are put into a Link-Down state. You can congure this number and is calculated by the ratio of the upstream port
bandwidth to the downstream port bandwidth in the same uplink-state group. This calculation ensures that there is no trac drops due to
insucient bandwidth on the upstream links to the routers/switches.
By default, if all upstream interfaces in an uplink-state group go down, all downstream interfaces in the same uplink-state group are put into
a Link-Down state.
Using UFD, you can congure the automatic recovery of downstream ports in an uplink-state group when the link status of an upstream
port changes. The tracking of upstream link status does not have a major impact on central processing unit (CPU) usage.
UFD and NIC Teaming
To implement a rapid failover solution, you can use uplink failure detection on a switch with network adapter teaming on a server.
For more information, refer to Network Interface Controller (NIC) Teaming.
Uplink Failure Detection (UFD)
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