Converged Enhanced Ethernet Administrator’s Guide 61
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MSTP overview 7
DRAFT: BROCADE CONFIDENTIAL
switch(conf-rstp)#hello-time 5
10. Set the method for flushing mac-addresses in FDB, either according to the IEEE standard or
the propriety standard. For details, see “Flushing MAC addresses (RSTP and MSTP)” on
page71.
switch(config)#spanning-tree tc-flush-standard
11. Enable PortFast on switch ports using the spanning-tree edgeport command. For details, see
“Enabling port fast (STP)” on page75. Note that this step is optional.
NOTE
Edgeport only needs to be enabled on ports that connect to workstations or PCs. Repeat these
commands for every port connected to workstations or PCs. Do not enable edgeport on ports
that connect to other switches.
switch(config)#interface tengigabitethernet 0/10
switch(conf-if-te-0/10)#spanning-tree edgeport
switch(conf-if-te-0/10)#exit
switch(config)#interface tengigabitethernet 0/11
switch(conf-if-te-0/11)#spanning-tree edgeport
switch(conf-if-te-0/11)#exit
Repeat these commands for every port connected to workstations or PCs.
12. Enable the guard root feature with the spanning-tree guard root command. The guard root
feature provides a way to enforce the root bridge placement in the network. For detailed
information, refer to“Enabling the guard root” on page73. Note that this step is optional.
Switch ports that recieve superior BPDUs are automatically placed in blocking mode.
This does not apply to ports connected to workstations or PCs; these ports remain in the
forwarding state.
13. Enter the copy command to save the running-config file to the startup -config file.
switch(conf-if-te-0/1)#do copy running-config startup-config
MSTP overview
The IEEE 802.1s Multiple STP (MSTP) helps create multiple loop-free active topologies on a single
physical topology. MSTP enables multiple VLANs to be mapped to the same spanning tree instance
(forwarding path), which reduces the number of spanning tree instances needed to support a large
number of VLANs. Each MSTP instance has a spanning tree topology independent of other
spanning tree instances. With MSTP you can have multiple forwarding paths for data traffic. A
failure in one instance does not affect other instances. With MSTP, you are able to more effective ly
utilize the physical resources present in the network and achieve better load balancing of VLAN
traffic.
NOTE
In MSTP mode, RSTP is automatically enabled to provide rapid convergence.
Multiple switches must be configured consistently with the same MSTP configuration to participate
in multiple spanning tree instances. A group of interconnected switches that have the same MSTP
configuration is called an MSTP region.