Ignition 8.1 gateway tries to connect with an external opc ua server. The server sends us (Ignition gateway) Signed Certificates. The device connection remains inactive unless we accept (Trust) the certificate on Ignition gateway side. Then the device connects straight away. This works great for one device, but what if we have hundreds of devices? Is there a way to automatically Trust signed certificates?
The only way this would work without intervention is if all of the servers were using certificates issued by a common CA, which you would add as a trusted certificate to Ignition's OPC UA client trust store.
You should get prompted to trust the certificate during the connection setup, rather than having to navigate to the security section after the fact.
OPC UA connections aren't defined programmatically right now anyway, so you'd have a chance to do this step for each connection you set up...