Using Tdr; Understanding Tdr - Cisco WS-CBS3032-DEL Software Configuration Manual

Chapter 48 Troubleshooting
4 171.9.4.5 0 msec 4 msec 0 msec
5 171.9.121.34 0 msec 4 msec 4 msec
6 171.9.15.9 120 msec 132 msec 128 msec
7 171.9.15.10 132 msec 128 msec 128 msec
Switch#
The display shows the hop count, the IP address of the router, and the round-trip time in milliseconds
for each of the three probes that are sent.
Table 48-2
Character
*
?
A
H
N
P
Q
U
To end a trace in progress, enter the escape sequence (Ctrl-^ X by default). Simultaneously press and
release the Ctrl, Shift, and 6 keys and then press the X key.

Using TDR

These sections contain this information:
•
•

Understanding TDR

You can use the Time Domain Reflector (TDR) feature to diagnose and resolve cabling problems. When
running TDR, a local device sends a signal through a cable and compares the reflected signal to the initial
signal.
TDR is supported only on 10/100/1000 copper Ethernet ports. It is not supported on 10-Gigabit Ethernet
ports and on SFP module ports.
TDR can detect these cabling problems:
•
•
If one of the twisted-pair wires is open, TDR can find the length at which the wire is open.
OL-13270-06
Traceroute Output Display Characters
Description
The probe timed out.
Unknown packet type.
Administratively unreachable. Usually, this output means that an access list is
blocking traffic.
Host unreachable.
Network unreachable.
Protocol unreachable.
Source quench.
Port unreachable.
Understanding TDR, page 48-15
Running TDR and Displaying the Results, page 48-16
Open, broken, or cut twisted-pair wires—The wires are not connected to the wires from the remote
device.
Shorted twisted-pair wires—The wires are touching each other or the wires from the remote device.
For example, a shorted twisted pair can occur if one wire of the twisted pair is soldered to the other
wire.
Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
Using TDR
48-15