Nokia ESB26 User Manual page 168

14.
Setting the Edge Port
The mstp edge-port command, in Interface Configuration mode, changes the admin status.
The no form of this command disables the admin status.
The EdgePort parameter is controlled by the MSTP state machine and the Command Line
Interface (CLI):
•
Admin EdgePort
The admin EdgePort parameter can be set by the CLI on a per-Port basis in order to
indicate that a given Port is permitted to transit directly to the Forwarding Port State when
a Port becomes Designated.
This functionality is provided in order to permit Bridge Ports that are (administratively)
known to be at the edge of the Bridged LAN to transition to Forwarding without delay.
However, as the presence of a Bridge on a Port that has been marked as an edge Port
could potentially cause a loop in the active topology, it is necessary to qualify the value of
the administrative state variable according to the port's knowledge of whether or not any
BPDUs have been received on the Port.
•
EdgePort
The Bridge Detection state machine controls the value of the corresponding operational
state variable, operational EdgePort, which may be used in order to determine whether a
port that becomes Designated is permitted to transit directly to Forwarding. A value of
enabled in the show commands indicates that this state transition is permitted to occur.
If a BPDU is received on the Port, then the value of operational EdgePort is set to
disabled. Following a port initialization, or following a link-up event, operational
EdgePort is set to the value of admin EdgePort.
Hence, if a Port that has been marked as an edge-port proves not to be one (due to the
presence of another Bridge), then it will cease to behave like an edge-port until such a
time as it is reinitialized (either by a link up/down event or by reissuing the CLI
command).
NOTE
If a BPDU is received on a port defined as an edge port, it automatically reverts to edge-port
disabled status. After link up/down or after the edge port command is used, the port returns
to the Admin status.
Command Syntax
device-name(config-if UU/SS/PP)#mstp edge-port
device-name(config-if UU/SS/PP)#no mstp edge-port
Setting the Link Type
The mstp link-type command, in Interface Configuration mode, sets the administrative status
of the MSTP port's link state. The no form of the command resets the port's administrative
link type to its default value (auto).
There are two statuses of link state: operational and administrative.
1. Admin Link-Type:
MN700004 Rev 01
Multiple Spanning Tree Protocol (MSTP)
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