SFP Communication and diagnostics

BotBlox Software
1

Hello,

I’m trying to query the SFP in slot 0 on the UbiSwitch, fw v1.2.0, and it’s returning the following error.

ubiswitch:~$ port 0 sfp
E: I2C transfer failed: -5
E: I2C transfer failed: -5
W: SFP is present but not responding at ADDR 0x50, REG 0x10
Failed IO

I’m reading other topics asking for SFP diagnostics such as RX and TX power which is what I need as well, so I’m guessing I wouldn’t be seeing that even if the command succeeded. Will RX and TX power diagnostics be supported in the near future? This would be very beneficial for us. Is there anything we can do to somehow extract this ourselves in the mean time?

Thank you

2

Hi there!

The error you’re seeing indicates that the UbiSwitch can detect the presence of an SFP, but it is unable to communicate with the module’s EEPROM over the I²C management interface.

Could you let us know the exact make and model number of the SFP module you’re using? If possible, a photo of the label on the module would also be helpful.

Additionally, could you please share how you are powering the UbiSwitch? SFP ports typically draw slightly more power so a limited power supply may be part of the problem.

A few other details that may help narrow this down:

  1. Is the issue reproducible after removing and reinserting the SFP?

  2. Have you tested the same SFP in another device, and if so, does it report vendor information or diagnostics correctly there?

  3. Are you using a fiber SFP, copper (RJ45) SFP, DAC, or AOC module?

  4. If you have another SFP available, does the same command produce the same error with that module?

Regarding diagnostics, the current implementation supports basic SFP diagnostics and identification functions, such as reading information from the SFP EEPROM (vendor ID, connector type, etc.) and monitoring electrical status signals such as RX_LOS and TX_FAULT.

RX/TX optical power monitoring is not currently supported. Those diagnostics are something we may add in a future software release, but we do not have a timeline to share at this time.

Once we know the exact SFP model and power setup, we can investigate further and determine whether this is a module compatibility issue, a power-related issue, or something else.

Thanks!