# OPC Connections - Fault

**URL:** <https://forum.inductiveautomation.com/t/opc-connections-fault/107854>\
**Category:** Ignition\
**Tags:** opcua\
**Created:** [June 26, 2025, 4:48pm UTC](https://forum.inductiveautomation.com/t/opc-connections-fault/107854 "2025-06-26T16:48:38Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![abdul.ramahi](https://avatars.discourse-cdn.com/v4/letter/a/22d042/32.png) [@abdul.ramahi](https://forum.inductiveautomation.com/u/abdul.ramahi)\
**Post date:** [June 26, 2025, 4:48pm UTC](https://forum.inductiveautomation.com/t/opc-connections-fault/107854/1 "2025-06-26T16:48:39Z")

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I am trying to connect Top Server to Ignition 8.1.48, each application is setup on a separate server on the same network. When I try to establish a new connection I keep getting the following error:  
Error: Bad\_timeout, connection timed out after 500 ms

if I use the same server to host both applications it would work fine.

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**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [June 26, 2025, 5:04pm UTC](https://forum.inductiveautomation.com/t/opc-connections-fault/107854/2 "2025-06-26T17:04:18Z")

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Check that the firewall on the server running Top Server is allowing inbound connections on whatever port it uses (49320? or does it use a different port than KEPServerEX?)

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<div class="post-metadata">

**Author:** ![abdul.ramahi](https://avatars.discourse-cdn.com/v4/letter/a/22d042/32.png) [@abdul.ramahi](https://forum.inductiveautomation.com/u/abdul.ramahi)\
**Post date:** [June 26, 2025, 5:06pm UTC](https://forum.inductiveautomation.com/t/opc-connections-fault/107854/3 "2025-06-26T17:06:12Z")

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im using port 49381 which is open. both servers can communicate freely with each other

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<div class="post-metadata">

**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [June 26, 2025, 5:10pm UTC](https://forum.inductiveautomation.com/t/opc-connections-fault/107854/4 "2025-06-26T17:10:58Z")

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> Error: Bad\_timeout, connection timed out after 500 ms

This means the server isn't responding when Ignition tries to open TCP connection. You would see the same in a Wireshark capture. It's usually a firewall or other networking issue when this occurs. Nothing to do on the Ignition side if you have the correct IP/hostname and port.

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<div class="post-metadata">

**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [June 26, 2025, 5:13pm UTC](https://forum.inductiveautomation.com/t/opc-connections-fault/107854/5 "2025-06-26T17:13:17Z")

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Also, fwiw, 500ms is not the default... somebody must have changed that. What else did they change and why?

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<div class="post-metadata">

**Author:** ![abdul.ramahi](https://avatars.discourse-cdn.com/v4/letter/a/22d042/32.png) [@abdul.ramahi](https://forum.inductiveautomation.com/u/abdul.ramahi)\
**Post date:** [June 26, 2025, 5:16pm UTC](https://forum.inductiveautomation.com/t/opc-connections-fault/107854/6 "2025-06-26T17:16:25Z")

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looks like I missed a 0, its 5000ms.

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<div class="post-metadata">

**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [June 26, 2025, 5:21pm UTC](https://forum.inductiveautomation.com/t/opc-connections-fault/107854/7 "2025-06-26T17:21:09Z")

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Ah, yeah, that's the default. Unlikely to be related to the issue at hand...