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Fibre Internet Service Troubleshooting Guide

Introduction

This guide provides troubleshooting steps for a fibre internet service. It covers common issues, their possible causes, and how to resolve them. This guide is applicable whether your fibre service connects via a Fibre LC connector or RJ45.

Prerequisites

  • Access to the physical equipment (NTU/NTD, router, and connected devices).
  • The login credentials for your modem/router's management interface.
  • Knowledge of your assigned static IP address and DNS servers.

Initial Checks

1. Check Physical Connections

  • Ensure all cables are securely connected:
    • If using Fibre LC, ensure the connector is properly seated in the NTU/NTD.
    • If using RJ45, confirm the Ethernet cable is firmly plugged into both the NTU/NTD and your router/firewall.
  • If possible, replace cables to rule out faulty wiring.

2. Check Power

  • Ensure that the NTU/NTD and your modem/router are powered on.
  • Verify that the power indicators (typically a green light) on both devices are lit. If not:
    • Check the power cables and outlets.
    • Try plugging the devices into a different power outlet.

3. Check Light Indicators on NTU/NTD

Most NTUs/NTDs have status LEDs that indicate the state of the connection. Here’s what the light indicators typically represent:

  • Power Light:
    • Solid Green: Device is powered on.
    • Off: No power, check the power source.
  • Link Light (for Fibre LC connection):
    • Solid Green: Fibre link is active and working.
    • Flashing Green: Fibre link is attempting to establish or is unstable.
    • Red or Off: No link detected; check the fibre cables and connectors.
  • WAN or Ethernet Light (for RJ45 connection):
    • Solid Green: Ethernet link is established.
    • Flashing Green: Data is being transmitted or received.
    • Red or Off: No Ethernet connection detected; check the RJ45 cable and ports.

4. Verify Internet Status

  • If your modem/router has an internet indicator light, check its status:
    • Solid Green: Connection is established.
    • Flashing Green: The connection is attempting to establish.
    • Red or Off: No internet connection is detected.

Modem/Router Configuration Checks

1. Log into the Management Interface

  • Access your modem/router’s management interface using the default IP (typically 192.168.1.1 or 192.168.0.1).
  • Log in using your credentials.

2. Check WAN Settings

  • Navigate to the WAN or Internet settings page.
  • Ensure that the Connection Type is set to Static IP.
  • Verify that the static IP address, subnet mask, gateway, and DNS settings are entered correctly as per your handover document:
    • IP Address: (Check the static IP assigned to your service)
    • Subnet Mask: (Ensure it matches the one provided, typically /30)
    • Gateway: (Ensure this matches the gateway provided in your handover document)
    • DNS Servers:
      • Primary: 202.3.111.123
      • Secondary: 202.3.111.124
  • If any of the details are incorrect, update them and save the configuration.

3. Check for Errors in Logs

  • Most modem/routers have a Logs or System Information page.
  • Look for any errors related to the WAN connection, such as:
    • No Link Detected: Indicates that no fibre or Ethernet connection is detected.
    • DHCP Failure (if applicable): Indicates failure in obtaining an IP address (ensure you're using static IP).
    • Authentication Issues: Could indicate incorrect credentials or configuration errors.

Common Troubleshooting Scenarios

If the Link Light on the NTU/NTD is red or off: - Check that the fibre cable (if using LC) is undamaged and properly seated in the NTU/NTD. - Try unplugging and replugging the fibre/RJ45 cable. - If the issue persists, try replacing the cable.

2. Internet Light is Off or Red

  • Ensure the static IP, subnet mask, and gateway are configured correctly.
  • Check for any service outages by contacting your internet provider.

3. Intermittent Connection

  • If the Link Light is flashing green or goes off intermittently:
    • This could indicate an unstable connection. Check the physical cables and connectors for any loose or damaged parts.
    • Ensure there are no kinks or tight bends in the fibre cable.
  • Check the signal strength if available in the NTU/NTD interface. A weak signal may indicate a problem with the fibre line itself.

4. Slow Internet Speeds

  • Check for network congestion or high usage on your internal network.
  • Run a speed test after verifying no other devices are using the connection.
  • If speeds are consistently slow, contact your provider to verify if any bandwidth restrictions or issues exist on their end.

DNS Issues

1. No DNS Resolution

  • If websites fail to load but the modem/router shows an active internet connection:
    • Check the DNS Settings in the modem/router configuration. Ensure the DNS servers are set to:
      • Primary: 202.3.111.123
      • Secondary: 202.3.111.124
    • Save the configuration and reboot the modem/router.

Advanced Troubleshooting

1. Ping and Trace

  • From your computer, open a command prompt/terminal and perform the following tests:

Ping the Gateway: ```bash ping

This will check if your modem/router can communicate with the NTU/NTD.

Ping a Public IP (e.g., Google):

ping 8.8.8.8

Traceroute:

tracert 8.8.8.8 (Windows)

traceroute 8.8.8.8 (macOS/Linux)

This will show the path your connection is taking to reach the destination, which can help identify where the issue is occurring.