Mstp Configuration Guidelines - Cisco 3020 - Catalyst Blade Switch Configuration Manual

Chapter 14 Configuring MSTP
Table 14-4 Default MSTP Configuration (continued)
Feature
Spanning-tree port priority (configurable on a per-CIST port basis)
Spanning-tree port cost (configurable on a per-CIST port basis)
Hello time
Forward-delay time
Maximum-aging time
Maximum hop count
For information about the supported number of spanning-tree instances, see the
Spanning-Tree Instances" section on page

MSTP Configuration Guidelines

These are the configuration guidelines for MSTP:
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OL-8915-01
When you enable MST by using the spanning-tree mode mst global configuration command, RSTP
is automatically enabled.
For two or more switches to be in the same MST region, they must have the same VLAN-to-instance
map, the same configuration revision number, and the same name.
The switch supports up to 65 MST instances. The number of VLANs that can be mapped to a
particular MST instance is unlimited.
PVST+, rapid PVST+, and MSTP are supported, but only one version can be active at any time. (For
example, all VLANs run PVST+, all VLANs run rapid PVST+, or all VLANs run MSTP.) For more
information, see the "Spanning-Tree Interoperability and Backward Compatibility" section on
page 13-10. For information on the recommended trunk port configuration, see the
Other Features" section on page
VTP propagation of the MST configuration is not supported. However, you can manually configure
the MST configuration (region name, revision number, and VLAN-to-instance mapping) on each
switch within the MST region by using the command-line interface (CLI) or through the SNMP
support.
For load balancing across redundant paths in the network to work, all VLAN-to-instance mapping
assignments must match; otherwise, all traffic flows on a single link.
All MST boundary ports must be forwarding for load balancing between a PVST+ and an MST
cloud or between a rapid-PVST+ and an MST cloud. For this to occur, the IST master of the MST
cloud should also be the root of the CST. If the MST cloud consists of multiple MST regions, one
of the MST regions must contain the CST root, and all of the other MST regions must have a better
path to the root contained within the MST cloud than a path through the PVST+ or rapid-PVST+
cloud. You might have to manually configure the switches in the clouds.
Default Setting
128.
1000 Mbps: 4.
100 Mbps: 19.
10 Mbps: 100.
2 seconds.
15 seconds.
20 seconds.
20 hops.
13-9.
10-17.
Cisco Catalyst Blade Switch 3020 for HP Software Configuration Guide
Configuring MSTP Features
"Supported
"Interaction with
14-15