Cisco Catalyst 2950 Command Reference Manual page 343

Chapter 2 Catalyst 2950 and 2955 Cisco IOS Commands
The Reed-Solomon errors show the number of errors detected and corrected in the data being received
on and sent from the switch LRE ports. Reed-Solomon errors are the result of noise exceeding the noise
margin. For short bursts of noise (such as motor power on or power surges), the interleaver prevents the
loss of Ethernet data packets. The number of Reed-Solomon errors then exceeds the number of Ethernet
CRC errors.
The Reed-Solomon errors are reset each time that you enter the show controllers lre status link
Note
command.
The remote transmit power levels from the connected CPE devices might be different from each other,
depending on how long the cable is between the switch and the CPE device. A longer cable typically
causes the CPE device to send a higher signal to overcome the loss effects of distance.
The local receive-power rates actually displays the switch's adjustment to the incoming power level.
These numbers might be different from LRE port to LRE port, as the length of the cables to the CPE
devices might be different.
The interleaver columns display the interleaver block size for both directions of data. A higher
interleaver setting is less susceptible to certain kinds of impairments but can introduce a very small
amount of delay in the data path.
The PMD-S column refers to physical media dependent status and is provided as diagnostic information.
For more information about what can affect the LRE link and for the minimum required SNR ratios, see
the "LRE Links and LRE Profiles" section in the "Configuring LRE" chapter of the switch software
configuration guide for this release.
The sequence and sequence detail keywords display these status codes of profiles and sequences during
rate selection:
•
•
•
•
•
You can adjust the noise level during convergence by using the margin interface configuration
command.
Use the show controllers lre status cpe [interface-id] privileged EXEC command to display
information about a specific CPE port or all the CPE ports.
Expressions are case sensitive. For example, if you enter | exclude output, the lines that contain output
do not appear, but the lines that contain Output appear.
Examples This is an example of output that shows link information for an LRE interface:
Switch# show controller lre status link longreachethernet0/2
Port
------ ---- ---- ----------- -------- ----------- ------------- -----
Lo0/2
This is an example of output from the show controllers lre status profile command:
0L-10102-01
Converged—Rate selection has converged on a profile.
Locked—Rate selection has converged on a profile, and the port is locked to that profile.
Executing—Rate selection is running on the port.
Waiting on Link—No link is established.
N/A—Sequence is not assigned to the port.
Link SNR RS Errs
(dB)
UP 41 4829
CPE-Tx Sw-AGC-Gain
(dBm/Hz) (dB) Rx-Bsz Tx-Bsz
- 57.7 - 7.6
Catalyst 2950 and Catalyst 2955 Switch Command Reference
show controllers lre status
Interleaver PMD-S
16 16 0x04
2-315