The QFX5110 100G interface would not come up when connected to a remote device via the CIENA DWDM device.
QFX5110:100G port--------DWDM----line-side----DWDM------100G:remote-device
QFX5110's 100G interface does not come up when connected to a remote device (any device) via the CIENA DWDM device. The laser level is in the range. Replacing and reseating the optics on both sides do not resolve the issue. However, when bypassing the CIENA DWDM device and connecting the remote device directly, both side's interfaces are up.
The QFX5110 showed the following symptoms:
The interface was showing the local fault:
test> show interfaces et-0/0/48 extensive Physical interface: et-0/0/48, Enabled, Physical link is Down >>>>>>snip<<<<<< Active alarms : LINK Active defects : LINK, LOCAL-FAULT <-- The LOCAL-FAULT is the active defects.
The QSFP28 shows the following alarm in problem status:
[the following output was taken by a vty command: show qsfp <index> alarm ]
Lane 0 >>>>>>snip<<<<<< Tx loss of signal: 106 Set <-- all 4 Lanes have this alarm and the counter(106) keeps increasing Rx CDR LOL: 2 Clear Tx CDR LOL: 106 Set Tx laser fault: 0 Clear Tx laser disable: 0 Clear Lane 1 >>>>>>snip<<<<<< Tx loss of signal: 106 Set Rx CDR LOL: 2 Clear Tx CDR LOL: 106 Set Tx laser fault: 0 Clear Tx laser disable: 0 Clear Lane 2 >>>>>>snip<<<<<< Tx loss of signal: 106 Set Rx CDR LOL: 2 Clear Tx CDR LOL: 106 Set Tx laser fault: 0 Clear Tx laser disable: 0 Clear Lane 3 >>>>>>snip<<<<<< Tx loss of signal: 106 Set Rx CDR LOL: 2 Clear Tx CDR LOL: 106 Set Tx laser fault: 0 Clear Tx laser disable: 0 Clear
This is an inter-op issue which is due to the QFX5110 responding to the initial "local fault" condition from the other side of the link and squelching the output. This creates a real "fault" which keeps the output squelched.
The QFX5110 internal logic has been updated to handle such conditions and avoid squelching per the following PR:
Fixed releases:
add it that