Cisco Fiber Troubleshooting with DOM

Cisco supports DOM (Digital Optical Monitoring) which is an industry standard to capture real time operating stastics such as:

-Optical Tx power
-Optcal Rx power
-Laser bias current
-Temparature
-Transceiver supply voltage

This is a great tool to use when troubleshooting Fiber interfaces. Please click on this link to see what Transceiver Modules are compatible:

Cisco Digital Optical Monitoring Compatibility Matrix

The command you would want to run is:

sh interface transceiver details

Below are some exmples:

Cisco Nexus:

COPPER:

N7K-1# sh int ethernet 1/11 transceiver
Ethernet1/11
    transceiver is present
    type is 1000base-T
    name is CISCO-AVAGO
    part number is ABCU-5710RZ-CS4
    revision is B2
    serial number is AGM173528GE
    nominal bitrate is 1300 MBit/sec
    Link length supported for copper is 100 m
    cisco id is --
    cisco extended id number is 4

As you can see, since it’s copper, you can’t pull real time statistics but you still get some good basic info.

FIBER:

N7K-1# sh int ethernet 1/10 transceiver
Ethernet1/10
    transceiver is present
    type is 10Gbase-SR
    name is CISCO-AVAGO
    part number is SFBR-709SMZ-CS1
    revision is G4.1
    serial number is AVA1732A0JK
    nominal bitrate is 10300 MBit/sec
    Link length supported for 50/125um OM2 fiber is 82 m
    Link length supported for 62.5/125um fiber is 26 m
    Link length supported for 50/125um OM3 fiber is 300 m
    cisco id is --
    cisco extended id number is 4
    cisco part number is 10-2415-03
    cisco product id is SFP-10G-SR
    cisco vendor id is V03

N7K-1# sh int ethernet 1/10 transceiver details
Ethernet1/10
    transceiver is present
    type is 10Gbase-SR
    name is CISCO-AVAGO
    part number is SFBR-709SMZ-CS1
    revision is G4.1
    serial number is AVA1732A0JK
    nominal bitrate is 10300 MBit/sec
    Link length supported for 50/125um OM2 fiber is 82 m
    Link length supported for 62.5/125um fiber is 26 m
    Link length supported for 50/125um OM3 fiber is 300 m
    cisco id is --
    cisco extended id number is 4
    cisco part number is 10-2415-03
    cisco product id is SFP-10G-SR
    cisco vendor id is V03
    number of lanes 1

           SFP Detail Diagnostics Information (internal calibration)
  ----------------------------------------------------------------------------
                Current              Alarms                  Warnings
                Measurement     High        Low         High          Low
  ----------------------------------------------------------------------------
  Temperature   18.03 C        75.00 C     -5.00 C     70.00 C        0.00 C
  Voltage        3.31 V         3.63 V      2.97 V      3.46 V        3.13 V
  Current        5.32 mA       10.50 mA     2.50 mA    10.50 mA       2.50 mA
  Tx Power      17.80 dBm      21.69 dBm    8.69 dBm   18.69 dBm     12.69 dBm
  Rx Power      17.06 dBm      22.00 dBm    6.09 dBm   18.99 dBm     10.09 dBm
  Transmit Fault Count = 0
  ----------------------------------------------------------------------------
  Note: ++  high-alarm; +  high-warning; --  low-alarm; -  low-warning

You can even run this command on a Cisco 2960-S. You just need to make sure that the module is DOM compatible.

2960-S:

Even though you can’t run the transceiver detail command on the copper ports, “sh interface controller” shows you good information about the port.
COPPER:

SW-1#sh int gig3/0/14 controller
GigabitEthernet3/0/14 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet, address is 08d0.9f55.800e (bia 08d0.9f55.800e)
  MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 1000Mb/s, media type is 10/100/1000BaseTX
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:56, output 00:00:31, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 204
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 80000 bits/sec, 110 packets/sec
     51072929 packets input, 16197174946 bytes, 0 no buffer
     Received 4275734 broadcasts (3849178 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 3849178 multicast, 0 pause input
     0 input packets with dribble condition detected
     2384635614 packets output, 257992839856 bytes, 0 underruns
     0 output errors, 0 collisions, 1 interface resets
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier, 0 PAUSE output
     0 output buffer failures, 0 output buffers swapped out

     Transmit GigabitEthernet3/0/14           Receive
    294917630 Bytes                       3312278732 Bytes
    150657164 Unicast frames                46797228 Unicast frames
   1450411612 Multicast frames               3849181 Multicast frames
    783567894 Broadcast frames                426557 Broadcast frames
            0 Too old frames              2592367121 Unicast bytes
            0 Deferred frames              619234867 Multicast bytes
            0 MTU exceeded frames           46148092 Broadcast bytes
            0 1 collision frames                   0 Alignment errors
            0 2 collision frames                   0 FCS errors
            0 3 collision frames                   0 Oversize frames
            0 4 collision frames                   0 Undersize frames
            0 5 collision frames                   0 Collision fragments
            0 6 collision frames
            0 7 collision frames             9534804 Minimum size frames
            0 8 collision frames             7929203 65 to 127 byte frames
            0 9 collision frames            24206443 128 to 255 byte frames
            0 10 collision frames            2406548 256 to 511 byte frames
            0 11 collision frames            1717867 512 to 1023 byte frames
            0 12 collision frames            5273135 1024 to 1518 byte frames
            0 13 collision frames                  0 Overrun frames
            0 14 collision frames                  0 Pause frames
            0 15 collision frames
            0 Excessive collisions                 0 Symbol error frames
            0 Late collisions                      0 Invalid frames, too large
            0 VLAN discard frames               4966 Valid frames, too large
            0 Excess defer frames                  0 Invalid frames, too small
    648247679 64 byte frames                       0 Valid frames, too small
   1358060506 127 byte frames
    312700310 255 byte frames                      0 Too old frames
     43161521 511 byte frames                      0 Valid oversize frames
      5343369 1023 byte frames                     0 System FCS error frames
     17095945 1518 byte frames                     0 RxPortFifoFull drop frame
        27340 Too large frames
            0 Good (1 coll) frames
            0 Good (>1 coll) frames

FIBER:

SW-1#sh int te1/0/1 transceiver detail
ITU Channel not available (Wavelength not available),
Transceiver is internally calibrated.
mA: milliamperes, dBm: decibels (milliwatts), NA or N/A: not applicable.
++ : high alarm, +  : high warning, -  : low warning, -- : low alarm.
A2D readouts (if they differ), are reported in parentheses.
The threshold values are calibrated.

                              High Alarm  High Warn  Low Warn   Low Alarm
          Temperature         Threshold   Threshold  Threshold  Threshold
Port       (Celsius)          (Celsius)   (Celsius)  (Celsius)  (Celsius)
--------- ------------------  ----------  ---------  ---------  ---------
Te1/0/1     35.1                75.0        70.0         0.0       -5.0

                              High Alarm  High Warn  Low Warn   Low Alarm
           Voltage            Threshold   Threshold  Threshold  Threshold
Port       (Volts)            (Volts)     (Volts)    (Volts)    (Volts)
---------  ---------------    ----------  ---------  ---------  ---------
Te1/0/1    3.29                  3.63        3.46        3.13       2.97

           Optical            High Alarm  High Warn  Low Warn   Low Alarm
           Transmit Power     Threshold   Threshold  Threshold  Threshold
Port       (dBm)              (dBm)       (dBm)      (dBm)      (dBm)
---------  -----------------  ----------  ---------  ---------  ---------
Te1/0/1     -2.5                 1.7        -1.3        -7.3      -11.3

           Optical            High Alarm  High Warn  Low Warn   Low Alarm
           Receive Power      Threshold   Threshold  Threshold  Threshold
Port       (dBm)              (dBm)       (dBm)      (dBm)      (dBm)
-------    -----------------  ----------  ---------  ---------  ---------
Te1/0/1     -3.0                 2.0        -1.0        -9.9      -13.9
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