# Displaying CIST port information

Use this procedure to display the CIST port information.

## Procedure steps

1. From the navigation tree, double-click VLAN.

2. From the VLAN tree, double-click Spanning Tree.

3. From the Spanning Tree folder, click MSTP.

4. Select the CIST Port tab.

## Variable definitions

The following table outlines the parameters of the CIST Port tab.

Table 1. MSTP CIST Port tab parameters
Variable | Value
--- | ---
Port | Identifies the port number of the port containing Spanning Tree information.
PathCost | SPecifies the contribution of this port to the cost of paths towards the CIST Root.
Priority | Displays the four most significant bits of the Port Identifier of the Spanning Tree instance. It can be modified by setting the CistPortPriority value. The values that are set for Port Priority must be in steps of 16.
DesignatedRoot | Specifies the unique Bridge Identifier of the bridge. Recorded as the CIST Root in the configuration BPDUs which are transmitted.
DesignatedCost | Specifies the path cost of the Designated Port of the segment connected to this port.
DesignatedBridge | Specifies the unique Bridge Identifier of the bridge which the port considers to be the Designated Bridge for the port segment.
DesignatedPort | Specifies the Port identifier of the port on the Designated Bridge which is designated for the port segment.
RegionalRoot | Displays the unique Bridge Identifier of the bridge. Recorded as the CIST Regional Root Identifier in the configuration BPDUs which are transmitted.
RegionalPathCost | Displays the contribution of this port to the cost of paths towards the CIST Regional Root.
ProtocolMigration | Indicates the Protocol migration state of this port. When operating in MSTP mode, set this field to true to force the port to transmit MSTP BPDUs without instance information.
| Note
| If this field is set to true and the port receives an 802.1d BPDU, the port begins transmitting 802.1d BPDUs. If the port receives an 802.1w BPDU, it begins transmitting 802.1w BPDUs.
AdminEdgeStatus | Specifies the administrative value of the Edge Port parameter. A value of true indicates that this port can be assumed to be an edge-port, and a value of false indicates that this port can be assumed to be a nonedge-port.
OperEdgeStatus | Signifies the operational value of the Edge Port parameter. This value is initialized to the value of AdminEdgeStatus and set to false when the port receives a BPDU.
AdminP2P | Displays the administrative point-to-point status of the LAN segment attached to this port. A value of 0 indicates that this port is always treated as being connected to a point-to-point link. A value of 1 indicates that this port is treated as having a shared media connection. A value of 2 indicates that this port is considered to have a point-to-point link if it is an Aggregator and all of its members are aggregatable, or if the MAC entity is configured for full duplex operation, either through auto-negotiation, or by management means.
OperP2P | Indicates the operational point-to-point status of the LAN segment attached to the port. It also indicates whether a port is considered to have a point-to-point connection. The value is determined by management or by auto-detection, as described in the AdminP2P object.
HelloTime | Displays the amount of time between the transmission of Configuration BPDUs transmitted by this node on the port. Measured in units of hundredths of a second.
OperVersion | Indicates whether the Port is operationally in the MSTP, RSTP, or STP-compatible mode; that is, whether the port is transmitting MST BPDUs, RST BPDUs, or Config/TCN BPDUs.
EffectivePortState | Displays the effective operational state of the port for CIST. This is set to true only when the port is operationally up in the Interface level and Protocol level for CIST. This is set to false for all other times.
State | Displays the current state of the port as defined by the Common Spanning Tree Protocol.
ForcePortState | Displays the current state of the port which can be changed to either Disabled or Enabled for the base Spanning Tree instance.
SelectedPortRole | Displays the selected port role for the Spanning Tree instance.
CurrentPortRole | Displays the current port role for the Spanning Tree instance.