Fiber NTU box has a red light or no light
Your fiber line to the provider is physically down. Do not poke at fiber connectors yourself; they are delicate.
Try this first
- 1Look at the lights on the small provider box (NTU or ONT). Power should be on; the signal or LOS light should be steady green (or OFF on some models).
- 2Red, blinking, or LOS lit = no fiber signal. Rarely caused by anything in your office.
- 3Do not unplug fiber connectors. A finger on the end = dirty = a technician has to come anyway.
- 4Call the provider with the serial or customer number on the box and report "NTU LOS" or "signal loss". They know what to schedule.
When to bring us in
For long fiber outages a 4G failover is handy: a backup router with a data SIM. We install that so you are never offline a full day again.
See also
- Wi-Fi drops randomly across the officeFirst rule out whether it is the access points or the internet connection itself. Different fix.
- One room or corner has no or bad Wi-FiNot always "add another AP"; often one is poorly positioned, or there is a metal wall in the way.
- Internet is suddenly slow for everyoneThree suspects: your provider, a colleague soaking the line, or a backup or update kicking in unexpectedly.
None of the above fits?
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