# SINUMERIK ONE OPC-UA Connection Warning

**URL:** <https://forum.inductiveautomation.com/t/sinumerik-one-opc-ua-connection-warning/101876>\
**Category:** Ignition\
**Tags:** opcua, ignition81\
**Created:** [February 4, 2025, 9:54pm UTC](https://forum.inductiveautomation.com/t/sinumerik-one-opc-ua-connection-warning/101876 "2025-02-04T21:54:18Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Ahiero](https://avatars.discourse-cdn.com/v4/letter/a/a698b9/32.png) [@Ahiero](https://forum.inductiveautomation.com/u/Ahiero)\
**Post date:** [February 4, 2025, 9:54pm UTC](https://forum.inductiveautomation.com/t/sinumerik-one-opc-ua-connection-warning/101876/1 "2025-02-04T21:54:18Z")

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When connecting to a Siemens SINUMERIK ONE control, I am receiving a warning message in the logs that a BasicConstraint cA bit is set on a self-signed certificate:  
 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/7/a/7ae9fdfa1e7afe3661254489f0085b161f9c77c3.png)

How should this be handled to not throw warnings in the logs regularly when the machine is connected?

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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:** [February 4, 2025, 11:49pm UTC](https://forum.inductiveautomation.com/t/sinumerik-one-opc-ua-connection-warning/101876/2 "2025-02-04T23:49:30Z")

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Aside from disabling that logger entirely there is nothing you can change.