# Checks you can run on your NBN® connection

> Category: NBN
> Canonical URL: https://crazytel.com.au/knowledgebase/article/nbn-checks-explained

How to check, restart and test your NBN® connection on Diagnostics & Faults, and what checks like Line State, Loopback Test, NTD Status and Port Reset mean.

Work through these steps in order. Many problems are fixed by the first two.


Where to go

Diagnostics & Faults › Choose a connection




The same steps are on each connection's Troubleshooting tab.




#2 Steps



- Check connection. Checks whether your connection is signed in to the network right now. It does not restart anything.

- Restart connection. Restart internet connection restarts your connection from the network side, like turning your modem off and on. Your modem reconnects by itself within about two minutes.

- Run a check. Check my NBN® box asks your box to check itself and its ports (internet stays on). Check service health shows the connection, speed and reliability the network reports. Check to run lists more checks for your connection type.

- Report a fault. Still not working? See Report an NBN® fault.




Heads up. Restarting drops anything using the internet for a moment, including internet phone calls. Checks that can interrupt your internet ask you to confirm first.




#2 What the check names mean



Line StateWhether your line is up and connected to the network.
Loopback TestThe connection between your NBN® equipment and the network.
NTD Status · WNTD StatusThe health of your NBN® box. WNTD is the Fixed Wireless box.
NTD · NCD · WNTD ResetRestarts your NBN® box from the network. Internet drops briefly.
UNI-D Port StatusThe port on the NBN® box your router plugs into.
Port ResetResets that port. Internet drops briefly.
DPU StatusOn Fibre to the Curb, the NBN® equipment in the pit outside.
Line Quality · SELT · Metallic Line TestTests of the copper line. The copper-line test needs your modem unplugged: tick My modem is unplugged and plug it back in afterwards.



#2 Health results



Looks healthyNo problem found.
Needs a closer lookSomething is below what it should be.
A problem was foundTry the guides below or report a fault.



Past results are on the Line checks and Health checks tabs.




#2 Related guides



- No internet: find the cause

- NBN® Pulse explained

- Report an NBN® fault