Configure RSTP

This task shows the traffic flow in the RSTP configuration on SEFOS running on the switch targets. This task verifies whether a loop is present in the topology, if it is detected, and if the traffic is blocked for the alternate port.

See Switching Feature Topology for the topology of this task.

1. Configure the initial settings.

   See Configure Initial Settings.

2. Configure VLAN forwarding in SEFOS-1 and SEFOS-2.

   See Configure VLAN Forwarding.

3. On SEFOS-1, verify the port status in RSTP mode.

   SEFOS-1# show spanning-tree
   Root Id          Priority   32768
                    Address    00:14:4f:6c:63:0f 
                    Cost       0
                    Port       0 [0]
                    Max Age 20 Sec, Forward Delay 15 Sec
    
   Spanning tree Protocol Enabled.
   Bridge is executing the rstp compatible Rapid Spanning Tree Protocol
   Bridge Id        Priority 32768
                      Address    00:14:4f:6c:63:0f
                      Cost       0
                      Port       0 [0]
                      Max Age 20 Sec, Forward Delay 15 Sec
    
   Spanning tree Protocol Enabled.
    
   Bridge is executing the rstp compatible Rapid Spanning Tree Protocol
   Bridge Id          Priority 32768
                      Address 00:14:4f:6c:63:0f
                      Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec
                      Dynamic Path Cost is Disabled
                      Dynamic Path Cost Lag-Speed Change is Disabled
   Name              Role         State        Cost     Prio   Type
   ----              ----         -----        ----     ----   ----
   Ex0/1                    Designated      Forwarding   2000     128      P2P
   Ex0/2                    Designated      Forwarding   2000     128      P2P
   Ex0/21                   Designated      Forwarding   2000     128      P2P
   Ex0/22                   Designated      Forwarding   2000     128      P2P
   ...

4. On SEFOS-2, verify the port status in RSTP mode.

   SEFOS-2# show spanning-tree
   Root Id         Priority   32768
                   Address    00:14:4f:6c:63:0f
                   Cost       4000
                   Port       Ex0/1
                   Max Age 20 Sec, Forward Delay 15 Sec
    
   Spanning tree Protocol Enabled.
    
   Bridge is executing the rstp compatible Rapid Spanning Tree Protocol
   Bridge Id       Priority 32768
                   Address 00:14:4f:6c:6e:0e
                   Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec
                   Dynamic Path Cost is Disabled
                   Dynamic Path Cost Lag-Speed Change is Disabled
   Name              Role         State        Cost     Prio   Type
   ----              ----         -----        ----     ----   ------
   Ex0/1                    Designated      Forwarding   2000     128      P2P
   Ex0/21                   root                Forwarding   2000     128      P2P
   Ex0/22                   Alternate    Discarding   2000     128     P2P
   ...

5. Ping from host A to host C.

   # ping -s 20.0.0.30

   Traffic is forwarded through the extreme-ethernet 0/21 port on SEFOS-1 to SEFOS-2 port 21.

6. Shut down the extreme-ethernet 0/21 port from SEFOS-2 and verify the port status.

   SEFOS-2# configure terminal
   SEFOS-2(config)# int ext 0/21
   SEFOS-2(config)# shut
   SEFOS-2(config)# exit
   SEFOS-2# show spanning-tree
   Root Id         Priority   32768
                   Address    00:14:4f:6c:69:0f
                   Cost       4000
                   Port       Ex0/1
                   Max Age 20 Sec, Forward Delay 15 Sec
    
   Spanning tree Protocol Enabled.
    
   Bridge is executing the rstp compatible Rapid Spanning Tree Protocol
   Bridge Id       Priority 32768
                   Address 00:14:4f:6c:6e:0e
                   Hello Time 2 sec, Max Age 20 sec, Forward Delay 15 sec
                   Dynamic Path Cost is Disabled
                   Dynamic Path Cost Lag-Speed Change is Disabled
   Name              Role         State        Cost     Prio   Type
   ----              ----         -----        ----     ----   ------
   Ex0/1             Designated   Forwarding   2000     128    P2P
   Ex0/21            Disabled     Forwarding   2000     128    P2P
   Ex0/22            root         Forwarding   2000     128    P2P
   ...

7. Ping from host A to host C.

   # ping 20.0.0.30

   Traffic should be forwarded through the extreme-ethernet 0/18 port on SEFOS-1. If RSTP is working, there will be a change in the port state.

Related Information

• Configure Initial Settings

• Configure VLAN Forwarding

• Configure LA

• Save a Configuration