Fibre Channel (SAN)

Reply
Occasional Contributor
Posts: 12
Registered: ‎01-09-2008

Do low SFP RX & TX Power levels indicate a hardware fault?

I have noticed the majority of the SFPs in our 4100 switches have tx power levels of between 300-400 uWatts. However there are a handful that are around the 260 uWatts level and these ports seem more likely to have enc_out errors.

Is this purely coincidental or does a low tx power (or rx power) level indicate a faulty cable, gbic or hba?

New Contributor
Posts: 3
Registered: ‎10-02-2008

Re: Do low SFP RX & TX Power levels indicate a hardware fault?

I have found in the past that replacing the SFP corrects these issues.

Occasional Contributor
Posts: 8
Registered: ‎12-22-2005

Re: Do low SFP RX & TX Power levels indicate a hardware fault?

I think remember that the optical loss budget is -20db. If the typical Tx/Rx power is 300 uW, it would seem, that an input power of 3 uW would be adequate. A varation of a db or two would be inconsequential on the RX side. On the Tx side however, I don't know if it could indicate a problem.

Join the Community

Get quick and easy access to valuable resource designed to help you manage your Brocade Network.

vADC is now Pulse Secure
Download FREE NVMe eBook