Viewing the topology message status

About this task

View topology message status to view the interconnections between Layer 2 devices in a network.

Procedure

To enter User EXEC mode, log on to the switch.
Show the contents of the topology table:

show autotopology nmm-table

Unless the witch is physically connected to other devices in the network, this topology will be blank.

Example

Note

In the following example, the column “ChassisType” uses a generic name. When you use the show autotopology nmm-table, your switch displays the actual chassis type.

Switch:1(config)#show autotopology nmm-table 
==========================================================================================
                                      Topology Table 
==========================================================================================
Local                                                                              Rem  
Port     IpAddress       SegmentId MacAddress   ChassisType            BT LS  CS   Port 
------------------------------------------------------------------------------------------
0/0      192.0.2.81     0x000000  0030ab707a00 ChassisType 1          12 Yes HtBt  0/0 
1/1      192.0.2.81     0x000000  0050ea268800 ChassisType 2          12 Yes HtBt  1/50 
1/42     192.0.2.81     0x000000  070ab307aa00 ChassisType 3          12 Yes HtBt  1/1 
2/1      192.0.2.81     0x000000  0030ab57ab00 ChassisType 4          12 Yes HtBt  1/49 
2/2      192.0.2.81     0x000000  0030ab307af0 ChassisType 5          12 Yes HtBt  1/50 
2/41     192.0.2.81     0x000000  00e0ba327c00 ChassisType 6          12 Yes HtBt  2/1 
2/42/1   192.0.2.81     0x000000  0050eb127400 ChassisType 7          12 Yes HtBt  1/2

Note

When a peer switch is running an older software version that does not include support for SONMP hello messages with channelization information, it can only show the slot/port. It cannot show the sub-port.

Job Aid

The following table describes the column headings in the command output for show autotopology nmm-table.

Table 1. Variable Definitions
Variable	Value
Local Port	Specifies the slot and port that received the topology message.
IpAddress	Specifies the IP address of the sender of the topology message.
SegmentId	Specifies the segment identifier of the segment from which the remote agent sent the topology message. This value is extracted from the message.
MacAddress	Specifies the MAC address of the sender of the topology message.
ChassisType	Specifies the chassis type of the device that sent the topology message.
BT	Specifies the backplane type of the device that sent the topology message. The switch uses a backplane type of 12.
LS	Indicates if the sender of the topology message is on the same Ethernet segment as the reporting agent.
CS	Specifies the current state of the sender of the topology message. The choices are topChanged—Topology information recently changed. HtBt (heartbeat)—Topology information is unchanged. new—The sending agent is in a new state.
Rem Port	Specifies the slot and port that sent the topology message.