Configuration Guide User guide

1154 FastIron Configuration Guide
53-1002494-02
STP feature configuration
STP load balancing
Notice that the STP groups each have different STP priorities. In configurations that use the STP
groups on multiple devices, you can use the STP priorities to load balance the STP traffic. By
setting the STP priorities for the same STP group to different values on each device, you can cause
each of the devices to be the root bridge for a different STP group. This type of configuration
distributes the traffic evenly across the devices and also ensures that ports that are blocked in one
STP group spanning tree are used by another STP group spanning tree for forwarding. Refer to
“Configuration example for STP load sharing” on page 1155 for an example using STP load sharing.
Configuring STP per VLAN group
To configure STP per VLAN group, perform the following tasks:
1. Configure the member VLANs.
2. Optionally, configure master VLANs to contain the member VLANs. This is useful when you
have a lot of member VLANs and you do not want to individually configure STP on each one.
Each of the member VLANs in the STP group uses the STP settings of the master VLAN.
3. Configure the STP groups. Each STP group runs a separate instance of STP.
The following CLI commands implement the STP per VLAN group configuration shown in
Figure 151. The following commands configure the member VLANs (3, 4, 13, and 14) and the
master VLANs (2 and 12). Notice that changes to STP parameters are made in the master
VLANs only, not in the member VLANs.
Brocade(config)#vlan 2
Brocade(config-vlan-2)#spanning-tree priority 1
Brocade(config-vlan-2)#tagged ethernet 1/1 to 1/4
Brocade(config-vlan-2)#vlan 3
Brocade(config-vlan-3)#tagged ethernet 1/1 to 1/4
Brocade(config-vlan-3)#vlan 4
Brocade(config-vlan-4)#tagged ethernet 1/1 to 1/4
Brocade(config-vlan-4)#vlan 12
Brocade(config-vlan-12)#spanning-tree priority 2
Brocade(config-vlan-12)#tagged ethernet 1/1 to 1/4
Brocade(config-vlan-12)#vlan 13
Brocade(config-vlan-13)#tagged ethernet 1/1 to 1/4
Brocade(config-vlan-13)#vlan 14
Brocade(config-vlan-14)#tagged ethernet 1/1 to 1/4
Brocade(config-vlan-14)#exit
The following commands configure the STP groups.
Brocade(config)#stp-group 1
Brocade(config-stp-group-1)#master-vlan 2
Brocade(config-stp-group-1)#member-vlan 3 to 4
Brocade(config-stp-group-1)#exit
Brocade(config)#stp-group 2
Brocade(config-stp-group-2)#master-vlan 12
Brocade(config-stp-group-2)#member-vlan 13 to 14
Syntax: [no] stp-group <num>
This command changes the CLI to the STP group configuration level. The following commands
are valid at this level. The <num> parameter specifies the STP group ID and can be from 1 –
32.