JunOS : fpc0 qsfp-0/0/0 failed to init hw

By | April 25, 2020

Encountering the following log event on your Juniper MX router?

fpc0 qsfp-0/0/0 failed to init hw

This could be caused by various factors, such as :

  • Defective FPC
  • Defective PIC
  • Defective transceiver
  • Incompatible transceiver*

*I have observed this error on customer equipment when DAC cables were used. The Juniper MX series does not officially support the usage of DAC cables. Even though they may be working while logging this error, I highly recommend replacing with optical transceiver to be in full compliance with the manufacturer recommendations and get rid of this error.

If the issue isn’t caused by DAC cables, I would first attempt to replace the transceiver with a known good and compatible unit. If the issue is still present, try to reboot the router, look for any known issues that could involve your JunOS version and finally, open a JTAC case. It happened to me once with a brand new router, where the issue was hardware related and the unit has to be replaced.