Cisco Systems Cisco IOS XR manual Verifying Bidirectionality

Chapter 3 Bringing Up the Cisco IOS XR Software on a Multishelf System

Integrated Switch System

Verifying Bidirectionality

To verify the bidirection for the integrated switch, you can use the Unidirectional Link Detection (UDLD) protocol to detect unidirectional links on Ethernet ports. UDLD is a Layer 2 protocol. UDLD is useful at linkup time. If the link is detected to be unidirectional, the port is shut down. In addition, UDLD detects unidirectional failures after a port has been up and bidirectional for a certain time. If a transceiver goes wrong, UDLD protects the control network from faulty transceivers that are plugged into the control network.

To provide the port information that is disabled (UDLD), use the show controllers switch udld ports command.

Verifying Unidirectional Link Detection (UDLD) Protocol Information

To verify Unidirectional Link Detection (UDLD) protocol information for intra-rack switches, use the

show controllers switch inter-rack udld location command, as shown in the following example:

RP/0/RP0/CPU0:router(admin)# show controllers switch inter-rack udld all location

f0/sc0/cpu0

Interface Gig port# 13

---

…

Current bidirectional state: Bidirectional

Current operational state: Advertisement - Single neighbor detected

…

…

Entry 1

---

…

Device name: 0_RP0_CPU0_Switch

Port ID: GE_Port_0

Neighbor echo 1 device: nodeF0_SC0_CPU0

Neighbor echo 1 port: Gig port# 13

Verifying Spanning Tree Protocol Information

To verify Spanning Tree Protocol (STP) information for intra-rack switches, use the show controllers switch stp location command, as shown in the following example:

RP/0/RP0/CPU0:router(admin)# show controllers switch stp location f0/sc0/CPU0

##### MST

0

vlans mapped:

2-4094

Bridge

address

0800.453e.469a

priority

36864

(36864

sysid 0)

Root

address

5246.48f0.20ff

priority

32768

(32768

sysid 0)

port

GE_Port_0

path cost

0

Regional Root

address

5246.48f0.20ff

priority

32768

(32768

sysid 0)

internal

cost

20000 rem hops

3

Operational

hello time

1, forward delay

6,

max age

8, txholdcount

6

Configured

hello time

1, forward delay

6,

max age

8, max hops

4

Interface

Role

Sts Cost

Prio.Nbr Type

---------------- ----

--- --------- -------- ---------------------------

##### MST

1

vlans mapped:

1

Bridge

address

0800.453e.469a

priority

36865

(36864

sysid 1)

Root

address

5246.48f0.20ff

priority

32769

(32768

sysid 1)

port

GE_Port_0

cost

20000 rem hops

3

Cisco IOS XR Getting Started Guide

OL-10957-02

3-27