Performing Mcheck - H3C S5120-SI Series Configuration Manual

To do...
Enter port
view or port
group view
Enable the MSTP feature for the
ports
To control MSTP flexibly, you can use the undo stp enable command to disable the MSTP feature for
certain ports so that they will not take part in spanning tree calculation and thus to save the CPU
resources of the device.

Performing mCheck

MSTP has three working modes: STP compatible mode, RSTP mode, and MSTP mode.
If a port on a device running MSTP (or RSTP) connects to a device running STP, this port will
automatically migrate to the STP-compatible mode. However, it will not be able to migrate automatically
back to the MSTP (or RSTP) mode, but will remain working in the STP-compatible mode under the
following circumstances:
The device running STP is shut down or removed.
The device running STP migrates to the MSTP (or RSTP) mode.
By then, you can perform an mCheck operation to force the port to migrate to the MSTP (or RSTP)
mode.
You can perform mCheck on a port through the following two approaches, which lead to the same
result.
Performing mCheck globally
Follow these steps to perform global mCheck:
Enter system view
Perform mCheck
Performing mCheck in port view
Follow these steps to perform mCheck in port view:
Enter Layer 2
Ethernet port view, or
Layer 2 aggregate
port view
Enter port group view
To do...
Use the command...
interface interface-type
interface-number
port-group manual
port-group-name
stp enable
Use the command...
system-view
stp mcheck
1-29
Remarks
Required
Use either command.
Optional
By default, MSTP is enabled for
all ports after it is enabled for the
device globally.
Remarks
—
Required