3Com S7902E, Руководство по настройке

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To do... Use the command... Remarks
Enable output of port state transition
information
stp port-log
{
all |
instance instance-id
}
Required
This function is enabled by
default.
Enabling the MSTP Feature
You must enable MSTP for the device before any other MSTP-related configurations can take effect.
Make this configuration on the root bridge and on the leaf nodes separately.
Follow these steps to enable the MSTP feature:
To do... Use the command... Remarks
Enter system view
system-view
—
Enable the MSTP feature globally
stp enable
Required
MSTP is globally disabled by
default.
Enter Ethernet
interface view, or
Layer 2 aggregate
interface view
interface interface-type
interface-number
Enter
interface view
or port group
view
Enter port group
view
port-group manual
port-group-name
Required
Use either command.
Enable the MSTP feature for the
ports
stp enable
Optional
By default, MSTP is enabled
for all ports after it is enabled
for the device globally.
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:
z
The device running STP is shut down or removed.
z
The device running STP migrates to the MSTP (or RSTP) mode.