Incorrect number formatting on Cisco Nexus 9396

I have two different issues here. Obviously, I don’t expect the LibreNMS community to fix the switch sending incomplete information. Hopefully, we can rectify the other, however.

  1. The switch returning incomplete information.
  2. The NMS formatting it incorrectly.

I have done the snmpget request in the same order as the screen shot from the NMS.

The snmpget isn’t returning all of the information one would care about (not enough digits for precision) and the NMS is introducing a few extra decimal points.

[redacted]:~$ /usr/bin/snmpget -v3 -l authPriv -u [redacted] -a SHA -A [redacted] -x AES -X [redacted] [redacted] .1.3.6.1.4.1.9.9.91.1.1.1.1.4.300003522 .1.3.6.1.4.1.9.9.91.1.1.1.1.4.300003524 .1.3.6.1.4.1.9.9.91.1.1.1.1.4.300003527 .1.3.6.1.4.1.9.9.91.1.1.1.1.4.300003533 .1.3.6.1.4.1.9.9.91.1.1.1.1.4.300003534
iso.3.6.1.4.1.9.9.91.1.1.1.1.4.300003522 = INTEGER: 3
iso.3.6.1.4.1.9.9.91.1.1.1.1.4.300003524 = INTEGER: 15
iso.3.6.1.4.1.9.9.91.1.1.1.1.4.300003527 = INTEGER: 39
iso.3.6.1.4.1.9.9.91.1.1.1.1.4.300003533 = INTEGER: -6
iso.3.6.1.4.1.9.9.91.1.1.1.1.4.300003534 = INTEGER: -6

       SFP Detail Diagnostics Information (internal calibration)

            Current              Alarms                  Warnings
            Measurement     High        Low         High          Low

Temperature 39.67 C 100.00 C -50.00 C 85.00 C -40.00 C
Voltage 3.35 V 3.79 V 2.80 V 3.46 V 3.13 V
Current 15.75 mA 90.00 mA 0.00 mA 85.00 mA 0.00 mA
Tx Power -6.10 dBm -1.50 dBm -10.50 dBm -3.00 dBm -9.03 dBm
Rx Power -6.12 dBm -3.00 dBm -26.98 dBm -5.00 dBm -23.97 dBm
Transmit Fault Count = 0

Note: ++ high-alarm; + high-warning; – low-alarm; - low-warning

That is the same problem. LibreNMS respects the mib and since the data is returned incorrectly, it is shown incorrectly. The mib specify how many decimal places to shift the the number (since SNMP only supports integers). This could even be down to the sfp itself reporting data incorrectly to the device.

All SFPs in the switch (around 37 SFPs of different makes\models) are exhibiting the same problem, so that part probably isn’t it.

So there’s not anything I can do?

I just compared same interfaces on another Nexus model and they had almost the same OIDs. That other switch is fine. sigh Cisco bug…