Failover Scenarios for PortChannels and FSPF Links
The SmartBits traffic generator was used to evaluate the scenarios displayed . Two links between switch
1 and switch 2 exist as either equal-cost ISLs or PortChannels. There is one flow from traffic generator
1 to traffic generator 2. The traffic was tested at 100 percent utilization at 1 Gbps in two scenarios:
- Disabling the traffic link by physically removing the cable.
- Shutting down either switch 1 or switch 2 .
Table 23-3 Physically Removing the Cable for the SmartBits Scenario
|
PortChannel Scenario
|
FSPF Scenario (Equal cost ISL)
|
|
Switch 1
|
Switch 2
|
Switch 1
|
Switch 2
|
|
110 msec (~2K frame drops)
|
130+ msec (~4k frame drops)
|
|
100 msec (hold time when a signal loss is reported as mandated by the standard)
|
|
Table 23-4 Shutting Down the Switch for the SmartBits Scenario
|
PortChannel Scenario
|
FSPF Scenario (Equal cost ISL)
|
|
Switch 1
|
Switch 2
|
Switch 1
|
Switch 2
|
|
~0 msec (~8 frame
drops)
|
110 msec (~2K frame
drops)
|
130+ msec (~4K frame drops)
|
|
No hold time needed
|
Signal loss on switch 1
|
No hold time needed
|
Signal loss on switch 1
|
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