Details
Minor Description
Since XOS 22.3.1.4 or some versions below Extreme added the feature to pull dBm values from the ports. Works "ok" so far... only interger values are support crap.
Observium is supporting this feature but during the convertion of this value it fails.
Converted DBM value: -7.0E-6 W -> FALSE |
And sensor_unit is wrong. Output is dBm. Attached debug log and a CLI output from the transceiver.
Attachments
Activity
Extreme released new firmware which contains a bug fix.
ExtremeXOS 22.7.1.2
Update: Extreme confirmed this bug opened a official bug ticket for this. Fetching values via SNMP for "entPhySensorEntry" gives incorrect values. CR#xos0073216
ahh, you mean used incorrect scale? 
we exactly use scale value from entPhySensorScale, if here incorrect value.. again write to vendor
I not see ways how to fix this case inside observium.
Mhhh... I converted the CLI value 3.39dBm to watt and get 0.0021827299118 Watt. But you're right... you're doing everything right.
Extreme should return:
entPhySensorValue.135 = 2184
or change scale to
entPhySensorScale.135 = milli
Do you agree with me?
entPhysicalDescr.135 = SFP TX Power Sensor
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entPhysicalDescr.136 = SFP RX Power Sensor
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entPhySensorValue.135 = 21849
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entPhySensorValue.136 = -9999
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entPhySensorType.135 = watts
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entPhySensorType.136 = watts
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entPhySensorScale.135 = micro
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entPhySensorScale.136 = micro
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Converted DBM value: 0.021849 W -> 13.394315646739 dBm
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Converted DBM value: -0.009999 W -> FALSE
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What incorrect?
Upgraded to latest Extreme XOS 22.4.1.4 patch1-3 ( ssh) which solved the issue but still invalid results. Now it looks like that the convertion from W to dBm is not working well. I get different results when using https://www.rapidtables.com/convert/power/dBm_to_Watt.html and that results are 99% matching the SNMP and CLI values.
Attached is a poller debug.
Ok, what I see.. this is exactly vendor bug.
Tx Power (dBm) : -6.00 Status : Normal
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Low Warn Threshold : -9.00 High Warn Threshold : -3.00
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Low Alarm Threshold : -10.00 High Alarm Threshold : -2.00
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Rx Power (dBm) : -7.78 Status : Normal
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Low Warn Threshold : -21.02 High Warn Threshold : -3.00
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Low Alarm Threshold : -22.01 High Alarm Threshold : -2.00
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entPhySensorValue.275 = -5
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entPhySensorValue.276 = -7
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entPhySensorType.275 = watts
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entPhySensorType.276 = watts
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entPhySensorScale.275 = micro
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entPhySensorScale.276 = micro
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Device reported raw dbm values instead watts (also ignored/incorrect scale). Or scale is correct, but value anyway incorrect.
Try update firmware of write to vendor support, here should be possitive values in watts.
I.e. -7.78 dBm = 0.0001666 W or with scale micro values should be 167.
FYI... in XOS 31.6.1.3 this is still not fixed for all SFP+ modules. A FiberStore version of an Extreme CW57-10G-80-1570 continues to quantize reported Rx power levels to integer microwatts, thus losing a LOT of precision in the Observium graphs.