The switch s optical port has light but is down
We are experiencing issues with our optical ports between QFX5100 and EX4300 since we rebooted our EX4300 switch. 1840 V Module temperature high alarm : Off Module temperature low alarm : Off Module temperature high warning : Off. If you have physical access to the switch, it can save time to look at the port LEDs which give you the link status or can indicate an error condition (if red or orange). The triangle indicates the Tx (transmit) port with the pole facing outward on the SFP module, whereas the triangle indicates the Rx (receive) port with the bar facing inside. The link state is always active for a while (couple of hours to couple of days), and then change to link state "ready" and never come back until I power the whole switch down and up.
Read More