Diagnose Connection Problems

1. Fernhill SCADA
2. Help
3. Diagnose Connection Problems

Introduction

If you are having problems connecting to a Fernhill SCADA Server, follow these steps to find the cause of the problem:

• Check the Fernhill SCADA Server is running
• Check the Fernhill SCADA Server is listening on the correct TCP ports
• Check the firewall rules
• Try and connect locally
• Run a ping test from a remote computer

Check the Fernhill SCADA Server is running

Fernhill SCADA Server on Windows

On Windows, the Fernhill SCADA Server runs as a Windows Service. To check the Fernhill SCADA Server is running:

1. On the computer running the Fernhill SCADA Server, open the Control Panel.
2. Open Administrative Tools.
3. Open Services.
4. Scroll down until you see the entry for Fernhill SCADA Server:
   
5. Check the Status is Started.

   Note: If Status is not showing Started, open the service Properties and try to start the service. For more information, see Managing the SCADA Server.

Fernhill SCADA Server on Linux

On Linux, the Fernhill SCADA Server runs as a systemd service. To check the Fernhill SCADA Server is running:

1. Open a command prompt.
2. Enter this command:

   systemctl status fernhill-scada

   The output should be similar to:

   ● fernhill-scada.service - Fernhill SCADA Server for Unix
      Loaded: loaded (/lib/systemd/system/fernhill-scada.service; enabled; vendor preset: ...
      Active: active (running) since Tue 2018-08-28 14:48:15 BST; 2min 43s ago
     Process: 363 ExecStart=/usr/bin/fernhill-scada --pidfile /var/run/fernhill-scada.pid ...
    Main PID: 404 (fernhill-scada)
       Tasks: 10 (limit: 4915)
      CGroup: /system.slice/fernhill-scada.service
              └─404 /usr/bin/fernhill-scada --pidfile /var/run/fernhill-scada.pid --daemon

3. Check the Active: line shows active (running).

   Note: If the Active: does not show running, try and start the service. For more information, see Managing the SCADA Server.

Check the Fernhill SCADA Server is listening on the correct TCP Port

By default, the Fernhill SCADA Server accepts connections on TCP port 20295. Note: The TCP Port used by Fernhill SCADA can be changed using Server Parameters.

Fernhill SCADA Server on Windows

To check the Fernhill SCADA Server is listening on the correct ports on a Windows Computer:

1. On the computer running the Fernhill SCADA Server, open a Command Prompt with administrator privileges.
2. At the command prompt enter this command:
   

   netstat -naob -p TCP

3. Check the results contain entries for the Fernhill SCADA Service FHSvrService.exe listening on TCP Port 20295:
   
   

   Note: If another program is listening on either of the ports there is a port conflict. Try to change the configuration the other program to remove the port conflict.

Fernhill SCADA Server on Linux

To check the Fernhill SCADA Server is listening on the correct ports on a Linux computer:

1. On the computer running the Fernhill SCADA Server, open a Command Prompt.
2. Depending on how you run privileged commands on your Linux distribution, do one of the following:
   • Enter this command:

     sudo lsof -i -P -n | grep LISTEN

   • Enter these commands:

     su root
     lsof -i -P -n | grep LISTEN

3. Check the results contain entries for the Fernhill SCADA Service fernhill-scada listening on TCP Port 20295:
   

   fernhill- 404  root   24u  IPv4  13757      0t0  TCP *:20295 (LISTEN)
   fernhill- 404  root   25u  IPv6  13758      0t0  TCP *:20295 (LISTEN)

   Note: If another program is listening on either of the ports there is a port conflict. Try to change the configuration the other program to remove the port conflict.

Check a Firewall is not Blocking the Fernhill SCADA Server

The Fernhill SCADA setup program automatically adds rules to the Windows Firewall to grant network access to the Fernhill SCADA Server. It is possible another user or program has modified, or removed, these rules which prevents programs connecting to the Fernhill SCADA Server.

To check the Windows Firewall Rules:

1. On the computer running the Fernhill SCADA Server, open the Control Panel.
2. Open Windows Firewall.
3. Click Allow a program or feature through Windows Firewall
4. Scroll down the list and check there is an entry for the Fernhill SCADA Server:
   
   

   Note: If firewall rules are missing try to rerun the setup program in repair mode to reinstate the firewall rules.

It is possible another firewall product is blocking access. For example:

• An additional software firewall installed on the computer running the Fernhill SCADA Server.
• A network device performing the function of a firewall.

Configure any additional firewalls to accept connections on TCP Port 20295.

Try and connect locally

Run the operator interface on the computer running the Fernhill SCADA Server. This will the whether local connections are possible:

1. On the computer running the Fernhill SCADA Server, start the operator interface. Use the method described in Start the Operator Interface From the Windows Start Menu.
2. Click Connect to a Fernhill SCADA Server.
3. Enter localhost in the Computer Name field.
4. Click OK. Confirm the default graphic page opens.

Submit a bug report if you still cannot connect locally and all of the following are true:

• The Fernhill SCADA Service is running.
• The Fernhill SCADA Server is listening on TCP Port 20295.
• The Windows Firewall allows connections on TCP Port 20295.
• No other firewall product is blocking TCP Port 20295.

Submit a bug report to support@fernhillsoftware.com. Try and include the server log file for the connection attempt.

Run a ping test from a remote computer

You can run a ping test to check the network connection between two computers. A successful ping test will show you have a working network connection between two computers. A failed ping tests does not mean the network connection is not working. A ping test can fail because firewall rules are blocking ICMP Echo requests.

To run a ping test

1. On the remote computer open a Command Prompt.
2. At the command prompt enter this command:
   

   ping Address

   Where Address is the IP address of the computer running the Fernhill SCADA Server.

If the ping test succeeds you will see output like:

Pinging 192.168.1.218 with 32 bytes of data:
Reply from 192.168.1.218: bytes=32 time<1ms TTL=128
Reply from 192.168.1.218: bytes=32 time<1ms TTL=128
Reply from 192.168.1.218: bytes=32 time<1ms TTL=128
Reply from 192.168.1.218: bytes=32 time<1ms TTL=128

Ping statistics for 192.168.1.218:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms

If the ping test fails you will see output like:

Pinging 192.168.1.218 with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.

Ping statistics for 192.168.1.218:
    Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

If the ping test fails check the Windows Firewall on the computer running the Fernhill SCADA Server allows ICMP Echo Requests. The Microsoft Technet article Nobody Can Ping My Computer provides details how to do this.

Further Information

Operator Interface

To more information about the Operator Interface.

Fernhill SCADA Server

To learn about the Fernhill SCADA Server.

Glossary

For the meaning of terms used in Fernhill SCADA.

Fernhill SCADA Version 4.1 (20231126.1). Copyright © 2012-2023 Fernhill Software Ltd: All rights reserved.