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Sun Ethernet Fabric Operating System

PVRST+ Administration Guide

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Document Information

Using This Documentation

Product Notes

Related Documentation

Acronyms and Abbreviations

CLI Command Modes

Feedback

Support and Accessibility

PVRST+ Overview

Protocol Description

Topology Example

Default Settings

Rapid STP

Bridge ID and Switch Priority

Election of the Root Switch

Port States

Port Roles

Rapid Convergence

Proposal Agreement Sequence

Topology Change and Topology Change Detection

VLAN Module

Configuring RSTP in PVRST+

Enable IPv6 Support and Assign IPv6 Addresses

Configure the Spanning-Tree Path Cost

Configure the Spanning Tree Link Type

Configure the Spanning-Tree portfast Setting

Configure Spanning Tree Timers

Display the Spanning Tree Status

Configure the Transmit Hold Count

Configure Encapsulation

Configure the BPDU Guard

Configure the Root Guard

Configuring the VLAN Module

Disable GVRP

Configuring Trunk and Access Ports

Configure a Trunk Port

Configure an Access Port

Set Up PVID on a Port

Configure VLANS and Display the PVRST+ Information for VLANs

Enable IPv6 Support and Assign IPv6 Addresses

Before you execute the following instructions, ensure that all of the switches are in their default configuration. Also, disable GVRP, and start and enable PVRST+ on all switches. In the default configuration, vlan 1 is the default VLAN. If you plan to use another VLAN ID as the default VLAN, you must configure and enable the VLAN ID.

In the following examples, ports are configured as trunk, and vlan 10 is enabled on all three switches. vlan 10 is also used to show spanning tree status on switch C. See VLAN Module for information about configuring the VLAN module.

After the topology stabilizes, switch A is elected as the root because it has the lowest MAC address. All ports on all switches, except port 57 on switch C, should be in forwarding state. Port 57 on switch C should be detected as an alternate port in the discarding state.

Complete the following task on all three switches before setting the priority on switch C for the STP. Note that the following examples are run on switch C and similar commands must be run on switches A and B as well.

  1. Enter the configuration mode.
    TOR-2 SEFOS# configure terminal
    TOR-2 SEFOS(config)#
  2. Disable the GVRP module.
    TOR-2 SEFOS(config)# set gvrp disable
    TOR-2 SEFOS(config)#
  3. Enable VLAN 10.
    TOR-2 SEFOS(config)# vlan 10
    TOR-2 SEFOS(config-vlan)# vlan active
    TOR-2 SEFOS(config-vlan)# exit
    TOR-2 SEFOS(config)#
  4. Configure and bring up port 1 and port 57 as trunk.
    TOR-2 SEFOS(config)# interface extreme-ethernet 0/1
    TOR-2 SEFOS(config-if)# switchport mode trunk
    TOR-2 SEFOS(config-if)# no shutdown
    TOR-2 SEFOS(config-if)# exit
    TOR-2 SEFOS(config)#
    TOR-2 SEFOS(config)# interface extreme-ethernet 0/57
    TOR-2 SEFOS(config-if)# switchport mode trunk
    TOR-2 SEFOS(config-if)# no shutdown
    TOR-2 SEFOS(config-if)# exit
    TOR-2 SEFOS(config)#
  5. Configure IP address and mask for VLAN 10.
    TOR-2 SEFOS(config)# interface vlan 10
    TOR-2 SEFOS(config-if)# shutdown
    TOR-2 SEFOS(config-if)# ip address 192.168.10.149 255.255.255.0
    TOR-2 SEFOS(config-if)# no shutdown
    TOR-2 SEFOS(config-if)# end
    TOR-2 SEFOS#
  6. Repeat Steps 1 - 5 on switches A and B with their own port numbers, IP addresses, and masks.
  7. After all three switches are properly configured and the spanning tree topology is stabilized, display the spanning tree information for VLAN 10 on switch C.

    Port 57 should be in discarding state.

    TOR-2 SEFOS# show spanning-tree vlan 10
     
    -----------------------------------------------------------------
     
    Spanning-tree for VLAN 10
    Root Id         Priority   32778
                    Address    00:14:4f:6c:56:6f
                    Cost       2000
                    Port       Ex0/1
                    Hello Time 2 Sec, Max Age 20 Sec, Forward Delay 15 Sec
     
    Spanning Tree Enabled Protocol PVRST
    Bridge Id       Priority 32778
                    Address 00:14:4f:6c:6e:0d
                    Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec
    Name     Role         State        Cost     Prio   Type
    ----     ----         -----        ----     ----   ------
    Ex0/1    Root         Forwarding   2000     128    P2P
    Ex0/57   Alternate    Discarding   2000     128    P2P
     
    TOR-2 SEFOS#
  8. Ping the VLAN 10 IP address of switch A or B from C.
    TOR-2 SEFOS# ping 192.168.10.199
    Reply Received From :192.168.10.199, TimeTaken : 160 msecs
    Reply Received From :192.168.10.199, TimeTaken : 110 msecs
    Reply Received From :192.168.10.199, TimeTaken : 90 msecs
     
    --- 192.168.10.199 Ping Statistics ---
    3 Packets Transmitted, 3 Packets Received, 0% Packets Loss
    TOR-2 SEFOS#
     
    TOR-2 SEFOS# ping 192.168.10.144
    Reply Received From :192.168.10.144, TimeTaken : 100 msecs
    Reply Received From :192.168.10.144, TimeTaken : 100 msecs
    Reply Received From :192.168.10.144, TimeTaken : 110 msecs
     
    --- 192.168.10.144 Ping Statistics ---
    3 Packets Transmitted, 3 Packets Received, 0% Packets Loss
    TOR-2 SEFOS#
  9. To display the effect of the bridge priority on the port spanning tree state, in switch C, set the priority for the STP.
    TOR-2 SEFOS# configure terminal
    TOR-2 SEFOS(config)# spanning-tree vlan 10 brg-priority 4096
    TOR-2 SEFOS(config)# end
    TOR-2 SEFOS#

    In the PVRST+ software, the spanning-tree parameters apply only to the specified VLAN.

    For brg-priority, you can provide a value from 0 to 61440 in increments of 4096. The priority you provide is combined with the VLAN ID to obtain the actual priority for the instance created for the VLAN. If you do not specify a value, the VLAN ID is combined with a default value of 32768. If the combined number is lower than the other switches, the more likely it is that the switch will be chosen as the root switch.

    Valid priority values are: 0, 4096, 8192, 12288, 16384, 20480, 24576, 28672, 32768, 36864, 40960, 45056, 49152, 53248, 57344, and 61440.


    Note - After you configure the bridge priority, you should confirm that switch C has been detected as the root and that port 1 of switch B is the alternate port.


  10. In switch A, review the spanning-tree information.
    NEM-1 SEFOS# show spanning-tree vlan 10
     
    -------------------------------------------------------------------
    Spanning-tree for VLAN 10
    Root Id         Priority   4106
                    Address    00:14:4f:6c:6e:0d
                    Cost       2000
                    Port       Ex0/7
                    Hello Time 2 Sec, Max Age 20 Sec, Forward Delay 15 Sec
     
    Spanning Tree Enabled Protocol PVRST
    Bridge Id       Priority 32778
                    Address 00:14:4f:6c:56:6f
                    Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec
    Name     Role         State        Cost     Prio   Type
    ----     ----         -----        ----     ----   ------
    Ex0/3    Designated   Forwarding   2000     128    P2P
    Ex0/7    Root         Forwarding   2000     128    P2P
    Ex0/20   Designated   Forwarding   2000     128    P2P
    NEM-1 SEFOS#
  11. In switch B, review the spanning-tree information.
    TOR-1 SEFOS# show spanning-tree vlan 10
     
    -------------------------------------------------------------------
    Spanning-tree for VLAN 10
    Root Id         Priority   4106
                    Address    00:14:4f:6c:6e:0d
                    Cost       2000
                    Port       Ex0/57
                    Hello Time 2 Sec, Max Age 20 Sec, Forward Delay 15 Sec
     
    Spanning Tree Enabled Protocol PVRST
    Bridge Id       Priority 32778
                    Address 00:14:4f:6c:69:ed
                    Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec
    Name     Role         State        Cost     Prio   Type
    ----     ----         -----        ----     ----   ------
    Ex0/1    Alternate    Discarding   2000     128    P2P
    Ex0/57   Root         Forwarding   2000     128    P2P
     
    TOR-1 SEFOS#
  12. In switch C, review the spanning-tree information.
    TOR-2 SEFOS# show spanning-tree vlan 10
     
    -------------------------------------------------------------------
    Spanning-tree for VLAN 10
     
    We are the root of the Spanning Tree
    Root Id         Priority   4106
                    Address    00:14:4f:6c:6e:0d
                    Cost       0
                    Port       0
                    Hello Time 2 Sec, Max Age 20 Sec, Forward Delay 15 Sec
    Spanning Tree Enabled Protocol PVRST
    Bridge Id       Priority 4106
                    Address 00:14:4f:6c:6e:0d
                    Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec
    Name     Role         State        Cost     Prio   Type
    ----     ----         -----        ----     ----   ------
    Ex0/1    Designated   Forwarding   2000     128    P2P
    Ex0/57   Designated   Forwarding   2000     128    P2P
     
    TOR-2 SEFOS#
  13. In switch C, reset the priority to the default value. Switch A should be reelected as root again.
    TOR-2 SEFOS# configure terminal
    TOR-2 SEFOS(config)# no spanning-tree vlan 10 brg-priority
    TOR-2 SEFOS(config)# end
    TOR-2 SEFOS#
  14. In switch A, review the spanning-tree information (it shows switch A is a root again).
    NEM-1 SEFOS# show spanning-tree vlan 10
     
    -------------------------------------------------------------------
    Spanning-tree for VLAN 10
    We are the root of the Spanning Tree
     
    Root Id         Priority   32778
                    Address    00:14:4f:6c:56:6f
                    Cost       0
                    Port       0
                    Hello Time 2 Sec, Max Age 20 Sec, Forward Delay 15 Sec
     
    Spanning Tree Enabled Protocol PVRST
    Bridge Id       Priority 32778
                    Address 00:14:4f:6c:56:6f
                    Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec
    Name     Role         State        Cost     Prio   Type
    ----     ----         -----        ----     ----   ------
    Ex0/3    Designated   Forwarding   2000     128    P2P
    Ex0/7    Designated   Forwarding   2000     128    P2P
    Ex0/20   Designated   Forwarding   2000     128    P2P
     
    NEM-1 SEFOS#