Port Type And Link Type; Edge Port - IBM RackSwitch G8000 Application Manual

Port Type and Link Type

Edge Port

© Copyright IBM Corp. 2011
Tree priority values are configured so that each routing switch is the root for a
different MSTP instance. All of the uplinks are active, with each uplink port backing
up the other.
1. Configure port membership and define the STGs for VLAN 1. Enable tagging
on uplink ports that share VLANs. Port 19 and port 20 connect to the Enterprise
Routing switches.
RS G8000(config)# interface port 19
RS G8000(config-if)# tagging
RS G8000(config-if)# exit
RS G8000(config)# interface port 20
RS G8000(config-if)# tagging
RS G8000(config-if)# exit
2. Add server ports 1 and 2 to VLAN 1. Add uplink ports 19 and port 20 to VLAN 1.
RS G8000(config)# vlan 1
RS G8000(config-vlan)# enable
RS G8000(config-vlan)# member 1,2,19,20
RS G8000(config-vlan)# stg 1
RS G8000(config-vlan)# exit
3. Configure MSTP: Spanning Tree mode, region name, and version.
RS G8000(config)# spanning-tree mstp name MyRegion
RS G8000(config)# spanning-tree mode mst
RS G8000(config)# spanning-tree mstp version 100
4. Configure port membership and define the STGs for VLAN 2. Add server
ports 3, 4, and 5 to VLAN 2. Add uplink ports 19 and 20 to VLAN 2. Assign
VLAN 2 to STG 2.
RS G8000(config)# vlan 2
RS G8000(config-vlan)# enable
RS G8000(config-vlan)# member 3,4,5,19,20
RS G8000(config-vlan)# stg 2
RS G8000(config-vlan)# exit
Note: Each STG is enabled by default.
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.
Edge ports send BPDUs to upstream STP devices like normal STP ports, but do 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:
RS G8000(config)# interface port <port>
RS G8000(config-if)# [no] spanning-tree edge
RS G8000(config-if)# exit
Chapter 10. Spanning Tree Protocols
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