3Com 5500-EI PWR Reference Manual page 242

Parameters
enable: Enables MSTP.
disable: Disables MSTP.
interface-list: Ethernet port list. You can specify multiple Ethernet ports by providing this argument in the
form of interface-list = { interface-type interface-number [ to interface-type interface-number ] } &<1-10>,
where &<1-10> means that you can provide up to 10 port indexes/port index ranges for this argument.
Description
Use the stp command in system view to enable/disable MSTP globally. Use the undo stp
command in system view to restore the MSTP state to the default globally.
Use the stp command in Ethernet port view to enable/disable MSTP on a port. Use the undo stp
command in Ethernet port view to restore the MSTP state to the default on a port.
Use the stp interface command in system view to enable or disable MSTP on specified ports.
By default, MSTP is enabled both globally and on ports.
Note that:
After you enable MSTP, the device works in STP-compatible mode, RSTP mode or MSTP mode
depending on the MSTP mode setting, which is configurable with the stp mode command.
To control MSTP flexibly, you can use the undo stp enable command to disable MSTP on ports
that are not intended to take part in spanning tree calculation and thus to save CPU resources.
After being enabled, MSTP dynamically maintains the spanning tree status of VLANs based on
received configuration BPDUs. After being disabled, it stops maintaining the spanning tree status.
Disabling MSTP on ports may result in data loops that can destabilize a network.
Related commands: stp mode.
Examples
# Enable MSTP globally.
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] stp enable
# Disable MSTP on Ethernet 1/0/1.
Disable MSTP on Ethernet 1/0/1 in Ethernet port view.
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] interface Ethernet 1/0/1
[Sysname-Ethernet1/0/1] stp disable
Disable MSTP on Ethernet 1/0/1 in system view.
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] stp interface Ethernet 1/0/1 disable
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