MCT Configuration Examples Using STP

Although MCT is considered an alternative to the Spanning Tree Protocol (STP), SPT can be enabled in an MCT configuration as an added protection for any Layer 2 loops. The following use-case scenarios demonstrate the use of Spanning Tree protocols in an MCT configuration:

Configuring the Per-VLAN Spanning Tree on the MCT Clients example demonstrates the use of STP in an MCT configuration.

The following example shows STP elements enabled on MCT clients. It is recommended that you enable STP only on MCT clients, not on MCT cluster devices.

The following figure shows the base configuration of the MCT cluster, MCT clients, and the associated link-aggregation. The scenario depicted is based on this network topology.
Note: The LAG IDs are locally significant only and need not be matching on the two ends of a LAG.
Figure 1. Using STP in an MCT Configuration

AGG-A (R1) Configuration

The following example presents the configuration for Router 1 (AGG-A) in the figure shown above.


!
lag "1" static id 1
 ports ethernet 1/1/1 ethernet 1/1/3 
 

lag "1" static id 2
 ports ethernet 1/1/5 ethernet 1/1/7 
 

lag "1" static id 3
 ports ethernet 1/2/1 ethernet 1/2/2 
 
!
vlan 2 name session-vlan by port
tagged lag 3
router-interface ve 2
!
vlan 3 name keep-alive-vlan by port
tagged ethe 1/1/12
router-interface ve 3
!
vlan 1905 name MAC-scaling-vlan by port
tagged ethe 1/1/15 to 1/1/16 eth 1/3/1 1/3/3 lag 1 to 3 ethe 1/1/15 to
1/1/16 ethe 1/2/1 to 1/2/2 ethe 1/2/4 ethe 1/3/1 ethe 1/3/3
!
hostname R1
!
link-keepalive ethe 1/1/1 to 1/1/3 ethe 1/1/5 to 1/1/7
hitless-failover enable
!
interface ve 2
ip address 21.1.1.1 255.255.255.0
!
interface ve 3

AGG-B (R2) Configuration

The following example presents the configuration for Router 2 (AGG-B) in the figure shown above.


!
lag "1" static id 1
 ports ethernet 1/1/17 ethernet 1/1/19
 

lag "1" static id 2
 ports ethernet 1/1/21 ethernet 1/1/23 
 

lag "1" static id 3
 ports ethernet 1/2/1 ethernet 1/2/3 
 
!
vlan 2 name session-vlan by port
tagged lag 3
router-interface ve 2
!
vlan 3 by port
tagged ethe 1/1/11
router-interface ve 3
!
vlan 1905 name MAC-scaling-vlan by port
tagged ethe 1/1/15 to 1/1/19 ethe 1/1/21

Client 1 Configuration

The following example presents the configuration for Client #1 in the figure shown above.


!
lag lag1 dynamic id 1
 ports ethernet 5/1/47 to 5/1/48
!
vlan 1905 by port
 tagged ethe 7/1/1 to 7/1/3 ethe 8/1/1 to 8/1/3 ethe 8/1/45 lag 1 
!
link-keepalive ethe 7/1/1 to 7/1/3 ethe 8/1/1 to 8/1/3

!
lldp run
end

Client 2 Configuration

The following example presents the configuration for Client #2 in the figure shown above.


!
lag lag1 dynamic id 1
ports ethernet 2/1/47 to 2/1/48

vlan 1905 name MAC-scaling-vlan by port
tagged ethe 1/1/1 to 1/1/3 ethe 1/1/45 ethe 3/1/1 to 3/1/3 lag 1
!
link-keepalive ethe 1/1/1 to 1/1/3 ethe 3/1/1 to 3/1/3
 
!
lldp run
end