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Troubleshooting Down or Flapping Ports

If a PortA Port (sometimes referred to as a Megaport) is the physical point of connection between your organization’s network and the Megaport network. is down (not passing traffic) or rapidly alternating between an up/down state (flapping), run through these troubleshooting steps to help identify the root cause of the service disruption.


You can verify Port status from the Megaport Portal. On the Services page in the Portal, find the Port and mouse over its icon. A message displays the status of the service. (The color of the icon also indicates the service status.)

Troubleshooting actions

Action Steps
Check for CRCCyclic redundancy check.
A type of error detection code used to detect transmission errors in data.
errors, packet drops, and device logs
Interface statistics and device logs can help identify which end of the cross connect is causing the fault, and the potential solution. For example, an increasing number of incoming errors on a network interface generally rules out that specific SFP (small form pluggable) and indicates a potential issue with other components of the cross connect.
Verify physical connections with the data center Open a ticket with the data center to perform the following tests:
  1. Check the cross connect for damages or cleaning, if needed.
  2. SFP models should align with the Interface Speed and Interface details in Megaport Technical Specifications.
  3. Ensure that the data center is transmitting adequate light outside of the demarcation point at its end of the connection. The data center should check the light at the demarcation point with a light reading meter.
Verify carrier circuit status (if any) Some cross connects are set through one or multiple carrier network devices before reaching the Megaport network. Verify that the device interfaces in the cross connect path are free of errors, and that transmit and receive optical levels are operating correctly.

Next steps

If the troubleshooting actions do not resolve your issue, contact support. Before requesting assistance, collect the following information.

  • Troubleshooting results – Provide all troubleshooting steps taken in detail. For example, if loops were placed, note their location and which direction they faced.
  • Data center ticket reference – Megaport requires the data center ticket number to ensure that a ticket has been opened, and works as a reference if we open a ticket. Providing the ticket to the data center helps expedite troubleshooting and provides information on work that has already been done.
  • Port status, Tx (transmitted) and Rx (received) optical levels, and device logs – Port status, optic light readings, and device logs are helpful in determining the potential cause of a down or flapping Port.
  • SFP model and specifications – SFP models should align with Megaport Technical Specifications.


For more information on when a field service technician is needed onsite at the data center, see Customer Field Services.

Last update: 2024-04-15