Optics and Hardware Configuration Guide for Cisco 8000 Series Routers, Cisco IOS XR Releases

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Optics and Hardware Configuration Guide for Cisco 8000 Series Routers, Cisco IOS XR Releases

Performance monitoring

Updated: June 16, 2026

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Introduces performance monitoring and outlines the main concept, process, task, principle, and reference areas in this section. Guides technical users to quickly locate the procedures and supporting data they need.

Performance monitoring covers performance-monitoring enablement, thresholds, and threshold crossing alert reporting for optics and coherent DSP controllers.

Performance monitoring

Performance monitoring (PM) parameters are used by service providers to gather, store, set thresholds for, and report performance data for early detection of problems.

  • Host-Intf-{n}-FEC-BER

  • Host-Intf-{n}-FEC-FERC

This table lists the details of the host PM parameters:

Feature Name

Release Information

Description

New Parameters for Performance Monitoring

 Release 24.2.11

In this release, we've added two new parameters for performance monitoring. These parameters allow you to check the quality of electrical signals between an ASIC or NPU and the 400G Digital Coherent QSFP-DD optical modules periodically. This helps to detect errors occurring during data transmission and link initialization.

This feature introduces new parameters Host-Intf-{n}-FEC-BER and Host-Intf-{n}-FEC-FERC in the show controllers coherentdsp command.

Additional details

Performance monitoring can be configured on optics controllers and coherent DSP controllers.

To stop performance monitoring on optics or coherent DSP controllers, use the perf-mon disable keyword.

Release 24.2.11 introduces these host PM parameters:

Table 1. Performance Monitoring Parameters

PM Parameter

Mode Type

Number of Host Interfaces

Description
Host-Intf-{n}-FEC-BER

Transponder

1

n =0

For example, Host-Intf-0-FEC-BER

Muxponder

4

n = 0, 1, 2, and 3.

For example:

  • Host-Intf-0-FEC-BER

  • Host-Intf-1-FEC-BER

  • Host-Intf-2-FEC-BER

  • Host-Intf-3-FEC-BER
Host-Intf-{n}-FEC-FERC

Transponder

1

n =0

For example, Host-Intf-0-FEC-FERC

Muxponder

4

n = 0, 1, 2, and 3

For example:

  • Host-Intf-0-FEC-FERC

  • Host-Intf-1-FEC-FERC

  • Host-Intf-2-FEC-FERC

  • Host-Intf-3-FEC-FERC

These parameters check the quality of electrical signals between an ASIC or NPU and the 400G Digital Coherent QSFP-DD optical modules. The Cisco IOS XR software installed on the router collects Bit Error Rate (BER) and Frame Error Counters (FERC) information from the optical modules and maintains history for 30-sec, 15-minute, and 24-hours intervals.

Note

You can check these signals for host interfaces in both transponder and muxponder mode.

Configure PM parameters

Use this task to enable performance monitoring and configure PM parameters on optics and coherent DSP controllers.

Performance monitoring (PM) thresholds and threshold crossing alert (TCA) report status can be configured for optics controllers and coherent DSP controllers.

Table 2. PM thresholds and TCA report status for optics controllers

PM parameters

Description

CD

Sets the CD (chromatic dispersion) threshold or TCA reporting status.

DGD

Sets the DGD (differential group delay) threshold or TCA reporting status.

LBC

Sets the LBC (laser bias current) threshold or TCA reporting status in mA.

FREQ-OFF

Sets the FREQ-OFF (low signal frequency offset) threshold or TCA reporting status in MHz.

OPR

Sets the OPR (optical power RX) threshold or TCA reporting status in uW or dBm.

OPT

Sets the OPT (optical power TX) threshold or TCA reporting status in uW or dBm.

OSNR

Sets the OSNR (optical signal-to-noise ratio) threshold or TCA reporting status.

PCR

Sets the PCR (polarization change rate) threshold or TCA reporting status.

PDL

Sets the PDL (polarization dependent loss) threshold or TCA reporting status.

RX-SIG

Sets the RX-SIG (receiving signal power) threshold or TCA reporting status in uW or dBm.

SNR

Sets the SNR (signal-to-noise ratio) threshold or TCA reporting status.

SOPMD

Sets the SOPMD (second order polarization mode dispersion) threshold or TCA reporting status.
Table 3. PM thresholds and TCA report status for coherent DSP controllers

PM parameters

Description

Q

Sets the Q threshold or TCA reporting status.

Q-margin

Sets the Q margin threshold or TCA reporting status.

EC-BITS

Sets the EC-BITS (error corrected bits) threshold or TCA reporting status.

PostFEC BER

Sets the post-FEC BER threshold or TCA reporting status.

PreFEC BER

Sets the pre-FEC BER threshold or TCA reporting status.

UC-WORDS

Sets the UC-WORDS (uncorrected words) threshold or TCA reporting status.

Host-Intf-0-FEC-BER

Sets the Host-Intf-0-FEC-BER threshold or TCA reporting status, where:

  • AVG specifies the number of corrected bits received from the host interface prior to a PM interval.

  • MIN specifies the minimum number of corrected bits received from the host interface over a subinterval and prior to a PM interval.

  • MAX specifies the maximum number of corrected bits received from the host interface over a subinterval and prior to a PM interval.

Host-Intf-0-FEC-FERC

Sets the Host-Intf-0-FEC-FERC threshold or TCA reporting status, where:

  • AVG specifies the number of frames received from the host interface during a subinterval.

  • MIN specifies the minimum number of frames received from the host interface with uncorrected errors over a subinterval and prior to a PM interval.

  • MAX specifies the maximum number of frames received from the host interface with uncorrected errors over a subinterval and prior to a PM interval.

Before you begin

Identify the controller that you want to configure and the PM parameters that you want to set.

Procedure

SUMMARY STEPS

  1. Enable performance monitoring and set the CD PM thresholds on the optics controller.
  2. Verify the running configuration on the optics controller.
  3. Verify the configured PM thresholds on the optics controller.
  4. Enable performance monitoring and set PM thresholds and TCA report status on the coherent DSP controller.
  5. Verify the running configuration on the coherent DSP controller.
  6. Verify the configured PM parameters on the coherent DSP controller.
  7. Verify the Host-Intf-0-FEC-BER and Host-Intf-0-FEC-FERC PM parameters on the coherent DSP controller.

DETAILED STEPS

1.

Enable performance monitoring and set the CD PM thresholds on the optics controller.

Example:

Router#config
Router(config)#controller optics 0/2/0/16
Router(config-Optics)#perf-mon enable
Router(config-Optics)#pm 30-sec optics threshold cd max 100
Router(config-Optics)#pm 30-sec optics threshold cd min -100
Router(config-Optics)#commit
2.

Verify the running configuration on the optics controller.

Example:

Router#show run controller optics 0/2/0/16
Thu May 13 20:18:55.957 UTC
controller Optics0/2/0/16
pm 30-sec optics threshold cd max 100
pm 30-sec optics threshold cd min -100
 perf-mon enable
!
3.

Verify the configured PM thresholds on the optics controller.

Check the Configured Threshold fields in the command output.

Example:

Router#show controller optics 0/2/0/16 pm current 30-sec optics 1
  Thu May 27 17:58:49.889 UTC
Optics in the current interval [17:58:30 - 17:58:49 Thu May 27 2021]
Optics current bucket type : Valid
             MIN       AVG       MAX      Operational      Configured      TCA   Operational      Configured     TCA
                                          Threshold(min)   Threshold(min) (min) Threshold(max)   Threshold(max) (max)
LBC[mA ]      : 0.0       0.0       0.0      0.0               NA              NO   100.0            NA              NO
OPT[dBm]     : -9.98     -9.98     -9.98    -15.09            NA              NO   0.00             NA              NO
OPR[dBm]     : -40.00    -40.00    -40.00   -30.00            NA              NO   8.00             NA              NO
CD[ps/nm]    : 0         0         0        -80000          -100         NO   100             100         NO
DGD[ps ]     : 0.00      0.00      0.00     0.00              NA              NO   80.00            NA              NO
SOPMD[ps^2]  : 0.00      0.00      0.00     0.00              NA              NO   2000.00          NA              NO
OSNR[dB]     : 0.00      0.00      0.00     0.00              NA              NO   40.00            NA              NO
PDL[dB]      : 0.00      0.00      0.00     0.00              NA              NO   7.00             NA              NO
PCR[rad/s]   : 0.00      0.00      0.00     0.00              NA              NO   2500000.00       NA              NO
RX_SIG[dBm]  : -40.00    -40.00    -40.00   -30.00            NA              NO   1.00             NA              NO
FREQ_OFF[Mhz]: 0         0         0        -3600             NA              NO   3600             NA              NO
SNR[dB]      : 0.00      0.00      0.00     7.00              NA              NO   100.00           NA              NO

Last clearing of "show controllers OPTICS" counters never
!
4.

Enable performance monitoring and set PM thresholds and TCA report status on the coherent DSP controller.

Example:

Router#config
Router(config)#controller CoherentDSP0/2/0/16
Router(config-CoDSP)#perf-mon enable
Router(config-CoDSP)#pm 30-sec fec report Q max-tca enable
Router(config-CoDSP)#pm 30-sec fec report Q-margin max-tca enable
Router(config-CoDSP)#pm 30-sec fec report Q min-tca enable
Router(config-CoDSP)#pm 30-sec fec report Q-margin min-tca enable
Router(config-CoDSP)#pm 30-sec fec threshold Q max 1200
Router(config-CoDSP)#pm 30-sec fec threshold Q-margin max 500
Router(config-CoDSP)#pm 30-sec fec threshold Q min 900
Router(config-CoDSP)#pm 30-sec fec threshold Q-margin min 280
Router(config-CoDSP)#commit
5.

Verify the running configuration on the coherent DSP controller.

Example:

Router#show run controller coherentdsp 0/2/0/16
Thu May 13 19:56:09.136 UTC
controller CoherentDSP0/2/0/16
 pm 30-sec fec report Q max-tca enable
 pm 30-sec fec report Q-margin max-tca enable
 pm 30-sec fec report Q min-tca enable
 pm 30-sec fec report Q-margin min-tca enable
 pm 30-sec fec threshold Q max 1200
 pm 30-sec fec threshold Q-margin max 500
 pm 30-sec fec threshold Q min 900
 pm 30-sec fec threshold Q-margin min 280
 perf-mon enable
 !
6.

Verify the configured PM parameters on the coherent DSP controller.

Check the highlighted threshold and TCA fields in the command output.

Example:

Router#show controllers coherentdsp 0/2/0/16 pm current 30-sec fec
Thu May 27 23:04:54.167 UTC
g709 FEC in the current interval [23:04:30 - 23:04:54 Thu May 27 2021]
FEC current bucket type : Valid
    EC-BITS   : 0                       Threshold : 111484000000           TCA(enable)  : YES
    UC-WORDS  : 0                       Threshold : 5                      TCA(enable)  : YES
                                      MIN       AVG        MAX      Threshold      TCA     Threshold     TCA
                                                                       (min)     (enable)    (max)     (enable)
PreFEC BER                     :     0E-15     0E-15     0E-15      0E-15        NO       0E-15        NO
PostFEC BER                    :     0E-15     0E-15     0E-15      0E-15        NO       0E-15        NO
Q[dB]                          :      0.00      0.00      0.00      9.00  YES 120.00  YES
Q_Margin[dB]                   :      0.00      0.00      0.00      2.80  YES  5.00   YES
 !
7.

Verify the Host-Intf-0-FEC-BER and Host-Intf-0-FEC-FERC PM parameters on the coherent DSP controller.

You can check these parameters in transponder mode and muxponder mode.

Example:

/* Example in transponder mode*/
RP/0/RP0/CPU0:ios#show controllers coherentDSP 0/1/0/4 pm current 30-sec fec
Tue Dec 19 23:11:06.781 UTC
 
g709 FEC in the current interval [23:11:00 - 23:11:06 Tue Dec 19 2023]
 
FEC current bucket type : Valid
    EC-BITS   : 550344268               Threshold : 83203400000            TCA(enable)  : YES
    UC-WORDS  : 0                       Threshold : 5                      TCA(enable)  : YES
 
                                      MIN       AVG        MAX      Threshold      TCA     Threshold     TCA
                                                                       (min)     (enable)    (max)     (enable)
PreFEC BER                     :   2.4E-04   2.5E-04   2.5E-04      0E-15        NO       0E-15        NO
PostFEC BER                    :     0E-15     0E-15     0E-15      0E-15        NO       0E-15        NO
Q[dB]                          :     10.80     10.80     10.80       0.00        NO        0.00        NO
Q_Margin[dB]                   :      3.60      3.60      3.60       0.00        NO        0.00        NO
Host-Intf-0-FEC-BER            :     0E-15   1.3E-13   2.3E-10      0E-15        NO       0E-15        NO
Host-Intf-0-FEC-FERC           :     0E-15     0E-15     0E-15      0E-15        NO       0E-15        NO

/* Example in muxponder mode*/
RP/0/RP0/CPU0:ios#show controllers coherentDSP 0/1/0/30 pm current 30-sec fec
Tue Dec 19 23:16:27.132 UTC
 
g709 FEC in the current interval [23:16:00 - 23:16:27 Tue Dec 19 2023]
 
FEC current bucket type : Valid
    EC-BITS   : 3258288607              Threshold : 83203400000            TCA(enable)  : YES
    UC-WORDS  : 0                       Threshold : 5                      TCA(enable)  : YES
 
                                      MIN       AVG        MAX      Threshold      TCA     Threshold     TCA
                                                                       (min)     (enable)    (max)     (enable)
PreFEC BER                     :   2.7E-04   2.8E-04   2.9E-04      0E-15        NO       0E-15        NO
PostFEC BER                    :     0E-15     0E-15     0E-15      0E-15        NO       0E-15        NO
Q[dB]                          :     10.70     10.70     10.70       0.00        NO        0.00        NO
Q_Margin[dB]                   :      3.50      3.50      3.50       0.00        NO        0.00        NO
Host-Intf-0-FEC-BER            :   1.0E+00     0E-15     0E-15      0E-15        NO       0E-15        NO
Host-Intf-1-FEC-BER            :     0E-15     0E-15     0E-15      0E-15        NO       0E-15        NO
Host-Intf-2-FEC-BER            :     0E-15     0E-15     0E-15      0E-15        NO       0E-15        NO
Host-Intf-3-FEC-BER            :     0E-15     0E-15     0E-15      0E-15        NO       0E-15        NO
Host-Intf-0-FEC-FERC           :     0E-15     0E-15     0E-15      0E-15        NO       0E-15        NO
Host-Intf-1-FEC-FERC           :     0E-15     0E-15     0E-15      0E-15        NO       0E-15        NO
Host-Intf-2-FEC-FERC           :     0E-15     0E-15     0E-15      0E-15        NO       0E-15        NO
Host-Intf-3-FEC-FERC           :     0E-15     0E-15     0E-15      0E-15        NO       0E-15        NO

PM thresholds and TCA report status are configured, and the controller PM output shows the configured values.

What to do next

Continue monitoring the PM output for threshold crossing alerts during normal operation.