Mitsubishi iQF Troubleshooting

If you’re having trouble connecting to the Mitsubishi iQF device, you may need to look at your server's TCP Global Parameters. Below are instructions that apply to an Ignition server, hosted on a Windows environment, attempting to connect to a Mitsubishi iQF device through its device connection settings.

Note: Before making any changes to these settings, we would recommend reaching out to your IT team to ensure that changing these settings will not have any harmful impact on other applications.

You can view the TCP Global Parameters by:

1. Opening your command prompt as Administrator.
2. Enter the command:

netsh interface tcp show global

In order to make a valid connection to your Mitsubishi iQF device, your TCP Global Parameters regarding Explicit Congestion Notification (ECN) Capability need to be configured one of two ways.

1. ECN Capability: Disabled
2. ECN Capability: Enabled
   Initial RTO: 1000

ECN is an optional feature in TCP/IP networks that provides congestion notification by marking packets that transmit parts of the network experiencing high levels of congestion.

Enabling ECN Capability can be accomplished through the following command below:

netsh interface tcp set global ecncapability=enabled

Once ECN Capability has been enabled, the Initial Retransmission Timer (RTO) needs to be set to 1000. RTO is the retransmission timeout TCP uses to retransmit lost segments. When TCP sends a segment the timer starts and stops when the acknowledgment is received. If the timer expires, then a timeout occurs and the segment is retransmitted.

Enter the command below to set the Initial RTO:

netsh interface tcp set global initialRTO=1000

After you have completed the steps above, you should be able to successfully connect your Mitsubishi iQF device. If you’re still having trouble connecting, feel free to reach out to the Ignition Support team for further assistance.