Foundry Networks Switch and Router User Manual

Foundry Switch and Router Installation and Configuration Guide
10 - 34 December 2000
Enabling or Disabling the Spanning Tree Protocol (STP)
The STP (IEEE 802.1d bridge protocol) is supported on all Foundry switches and routers. STP detects and
eliminates logical loops in the network. STP also ensures that the least cost path is taken when multiple paths
exist between ports or VLANs. If the selected path fails, STP searches for and then establishes an alternate path
to prevent or limit retransmission of data.
STP must be enabled at the system level to allow assignment of this capability on the VLAN level. On Foundry
Layer 2 Switches, STP is enabled by default. On Foundry routers, STP is disabled by default.
NOTE: The procedures in this chapter describe how to configure standard STP. For information about Foundry’s
IronClad STP, see “Configuring Spanning Tree Protocol (STP) and IronSpan” on page 12-1.
USING THE CLI
To enable STP for all ports on a Foundry switch or router:
BigIron(config)# spanning tree
Syntax: [no] spanning-tree
USING THE WEB MANAGEMENT INTERFACE
1. Log on to the device using a valid user name and password for read-write access. The System configuration
panel is displayed.
2. Select Enable next to Spanning Tree.
NOTE: For information about the Single and Fast checkboxes, see “Single Spanning Tree” on page 12-19
and “Fast Uplink Span” on page 12-18.
3. Click Apply to save the changes to the device’s running-config file.
4. Select the Save link at the bottom of the dialog. Select Yes when prompted to save the configuration change
to the startup-config file on the device’s flash memory.
Modifying STP Bridge and Port Parameters
You can modify the following STP Parameters:
• Bridge parameters – forward delay, maximum age, hello time, and priority
• Port parameters – priority and path cost
STP Bridge Parameters
You can configure the following STP parameters:
• Forward Delay – The period of time a bridge will wait (the listen and learn period) before forwarding data
packets. Possible values: 4 – 30 seconds. Default is 15.
• Maximum Age – The interval a bridge will wait for receipt of a hello packet before initiating a topology change.
Possible values: 6 – 40 seconds. Default is 20.
• Hello Time – The interval of time between each configuration BPDU sent by the root bridge. Possible values:
1 – 10 seconds. Default is 2.
• Priority – A parameter used to identify the root bridge in a network. The bridge with the lowest value has the
highest priority and is the root. Possible values: 0 – 65,535. Default is 32,768.
STP Port Parameters
Spanning Tree Protocol port parameters priority and path cost are preconfigured with default values. If the default
parameters meet your network requirements, no other action is required.
You can configure the following STP port parameters:
• Port Priority – This parameter can be used to assign a higher (or lower) priority to a port. In the event that
traffic is re-routed, this parameter gives the port forwarding preference over lower priority ports within a VLAN

Foundry Networks Switch and Router Specifications

General

Brand	Foundry Networks
Model	Switch and Router
Category	Switch
Language	English