Uplink Interface Connectivity
Configure Uplink Interface Connectivity
47
Best Practice User Guide for the Catalyst 3850 and Catalyst 3650 Switch Series
Configure an Uplink Interface to Connect to a Distribution Router (or Standalone Distribution
Switch)
Note
Use this configuration when connecting the switch stack to two standalone distribution switches (not
configured as a VSS or VPC pair). However, do not use the
spanning-tree portfast trunk
command for
switch configuration.
•
Ensure that the distribution VSS or VPC router side of the connections are configured the same and
that the EtherChannel is configured with the LACP active mode.
•
For additional resilience, the configured uplink interfaces should be located on different switches in
the switch stack.
•
Use the
spanning-tree portfast trunk
command to allow the switch side of the uplink to
immediately transition to a spanning-tree forwarding state when the link becomes available, because
routers do not participate in a spanning tree.
shows a switch stack having a separate EtherChannel to each distribution router. Each
EtherChannel is configured as a trunk with VLANs 10, 11, 12, 100, 200, and 999, with the native VLAN
set to 999.
connection to Distribution VSS or VPC switch 1
connection to Distribution VSS or VPC switch 1
connection to Distribution VSS or VPC switch 2