Configuring VLAN Spanning-Tree Protocol
You can configure the VLAN Spanning-Tree Protocol (VSTP) under the following hierarchy level:
- [edit protocols]
To configure the VLAN Spanning-Tree Protocol:
- Enable VSTP as the version of spanning-tree protocol to be configured:
(Optional) For compatibility with older bridges that do not support VSTP, you can run force VSTP to run as the original IEEE 802.1D Spanning-Tree Protocol (STP) version:
[edit ... protocols vstp]user@host# set force-version stpNote: If VSTP has been forced to run as the original STP version, you can revert back to VSTP by first removing the force-version statement from the configuration and then entering the clear spanning-tree protocol-migration configuration mode command.
Configure the interfaces that participate in the VSTP instance.
- Enable configuration of the interface:
[edit ... protocols vstp]
user@host# edit interface interface-name - Configure the interface priority:
[edit ... protocols vstp interface interface-name]
user@host# set priority interface-priority - (Optional) Configure the interface as an edge port:
[edit ... protocols vstp interface interface-name]
user@host# set edge
- Enable configuration of the interface:
- Enable configuration of a VLAN instance:
[edit ... protocols vstp]
user@host# edit vlan vlan-id - Configure the bridge priority
[edit ... protocols vstp vlan vlan-id]
user@host# set bridge-priority bridge-priorityFor more information, see Understanding Bridge Priority for Election of Root Bridge and Designated Bridge.
Configure hello BPDU timers.
- Configure the maximum expected arrival time of hello BPDUs:
[edit ... protocols vstp vlan vlan-id]
user@host# set max-age seconds - Configure the time interval at which the root bridge transmits
configuration BPDUs:
[edit ... protocols vstp vlan vlan-id]
user@host# set hello-time seconds
- Configure the maximum expected arrival time of hello BPDUs:
- (Optional) By default, the bridge port remains in the
listening and learning states for 15 seconds before transitioning
to the forwarding state. You can specify a delay from 4 through 20 seconds instead:
[edit ... protocols vstp vlan vlan-id]
user@host# set forward-delay seconds Configure the interfaces that participate in the VSTP instance.
- Enable configuration of the interface:
[edit ... protocols vstp vlan vlan-id]
user@host# edit interface interface-name - Configure the interface priority:
[edit ... protocols vstp vlan vlan-id interface interface-name]
user@host# set priority interface-priority - (Optional) Configure the interface as an edge port:
[edit ... protocols vstp vlan vlan-id interface interface-name]
user@host# set edge
- Enable configuration of the interface:
Verify the VSTP configuration:
[edit]vstp {force-version stp; # Optional.interface interface-name {priority interface-priority;cost interface-link-cost; # Optional.mode (p2p | shared);edge; # Optional.}vlan vlan-id {bridge-priority bridge-priority;max-age seconds;hello-time seconds;forward-delay seconds; # Optional.interface interface-name {priority interface-priority;cost interface-link-cost; # Optional.mode (p2p | shared);edge; # Optional.}}}}}