Default Mstp Configuration; Mstp Configuration Guidelines - Cisco Catalyst 2975 Software Configuration Manual

Configuring MSTP Features

Default MSTP Configuration

Table 17-4
Table 17-4 Default MSTP Configuration
Feature
Spanning-tree mode
Switch priority (configurable on a per-CIST port basis)
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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Catalyst 2975 Switch Software Configuration Guide
17-16
shows the default MSTP configuration.
When you enable MST by using the spanning-tree mode mst global configuration command, RSTP
is automatically enabled.
For two or more stacked 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 stack 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 16-11. For information on the recommended trunk port configuration, see the
Other Features" section on page
All stack members run the same version of spanning tree (all PVST+, rapid PVST+, or MSTP). For
more information, see the "Spanning-Tree Interoperability and Backward Compatibility" section on
page 16-11.
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.
Default Setting
PVST+ (Rapid PVST+ and MSTP are disabled).
32768.
128.
1000 Mbps: 4.
100 Mbps: 19.
10 Mbps: 100.
2 seconds.
15 seconds.
20 seconds.
20 hops.
16-10.
13-15.
Chapter 17 Configuring MSTP
"Supported
"Interaction with
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