Port Type And Link Type; Edge/Portfast Port; Link Type - Lenovo CN4093 Application Manual

Port Type and Link Type

Edge/Portfast Port

Link Type

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A port that does not connect to a bridge is called an edge port. Since edge ports are
assumed to be connected to non-STP devices (such as directly to hosts or servers),
they are placed in the forwarding state as soon as the link is up. Internal ports
(INTx) should be configured as edge ports.
Edge ports send BPDUs to upstream STP devices like normal STP ports, but should
not receive BPDUs. If a port with edge enabled does receive a BPDU, it
immediately begins working as a normal (non-edge) port, and participates fully in
Spanning Tree.
Use the following commands to define or clear a port as an edge port:
CN 4093(config)# interface port <port>
CN 4093(config-if)# [no] spanning-tree portfast
CN 4093(config-if)# exit
The link type determines how the port behaves in regard to Rapid Spanning Tree.
Use the following commands to define the link type for the port:
CN 4093(config)# interface port <port>
CN 4093(config-if)# [no] spanning-tree link-type <type>
CN 4093(config-if)# exit
where type corresponds to the duplex mode of the port, as follows:
p2p
 A full-duplex link to another device (point-to-point)
shared
 A half-duplex link is a shared segment and can contain more
than one device.
auto
 The switch dynamically configures the link type.
Note: Any STP port in full-duplex mode can be manually configured as a shared
port when connected to a non-STP-aware shared device (such as a typical
Layer 2 switch) used to interconnect multiple STP-aware devices.
Chapter 10: Spanning Tree Protocols
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