3Com Switch 7754, Configuration Manual

Page: 263 / 940

The mCheck Configuration 263
Configuring port priority in Ethernet port view
Changing port priority of a port may change the role of the port and put the port
into state transition.
A smaller port priority value indicates a higher possibility for the port to become
the root port. If all the ports of a switch have the same port priority value, the port
priorities are determined by the port indexes. Changing the priority of a port will
cause spanning tree regeneration.
You can configure port priorities according to actual networking requirements.
Configuration example
# Configure the port priority of Ethernet1/0/1 port in spanning tree instance 1 to
be 16.
1 Configure in system view.
<SW7750> system-view
[SW7750] stp interface ethernet1/0/1 instance 1 port priority 16
2 Configure in Ethernet port view.
<SW7750> system-view
[SW7750] interface ethernet1/0/1
[SW7750-Ethernet1/0/1] stp instance 1 port priority 16
Point-to-point
Link-Related
Configuration
Refer to “Point-to-point Link-Related Configuration” on page 256.
MSTP Configuration Refer to “MSTP Configuration” on page 258.
The mCheck
Configuration
As mentioned previously, ports on an MSTP-enabled switch can operate in three
modes: STP-compatible, RSTP-compatible, and MSTP.
A port on an MSTP-enabled switch operating as an upstream switch transits to the
STP-compatible mode when it has an STP-enabled switch connected to it. When
the STP enabled downstream switch is then replaced by an MSTP-enabled switch,
the port cannot automatically transit to the MSTP mode. It remains in the
STP-compatible mode. In this case, you can force the port to transit to the MSTP
mode by performing the mCheck operation on the port.
Similarly, a port on an RSTP-enabled switch operating as an upstream switch
transits to the STP-compatible mode when it has an STP enabled switch connected
to it. When the STP enabled downstream switch is then replaced by an
Table 195 Configure port priority for a specified port in Ethernet port view
Operation Command Description
Enter system view system-view -
Enter Ethernet port
view interface interface-type
interface-number
-
Configure port priority
for the port stp [ instance instance-id ] port
priority priority
Required.
The default port priority is 128.