The failover Kepware OPC UA server works the same as the OPC UA server with the exception that you need to have two copies of Kepware setup, preferably on different servers. The failover Kepware OPC UA server will be used in the event the primary Kepware server goes down. To enable failover, check the box to Show advanced properties in the New OPC UA Connection Settings, set the Failover Enabled property to 'true,' and specify the Failover Endpoint.
The Backup properties should be used when a pair of redundant Ignition Gateways are trying to look at the same Kepware OPC UA server. Both the Backup Discovery URL and Backup Endpoint URL properties need to be configured.
For additional information on Failover, refer to OPC UA Client Connection Settings.
No Anonymous Token Policy Found
When connecting to KepServer, some versions may not allow anonymous connections by default. This typically means you need to specify user credentials for Ignition to use in the OPC UA server connection. Alternatively, individual Kepware Projects can allow anonymous login. For more information, look into allowing "anonymous login" in KepServer's OPC UA Configuration Manager documentation.
Other UA Servers
While the above example is specific to KEPServerEX, the same concepts apply to connecting to any other third party OPC server that accepts OPC UA client connections. The only difference may be in the way that the certificates are accepted on the server.
The Ignition OPC UA server sends the client certificate to the third party OPC server when it tries to make the connection, however if the OPC server is not designed to expect these certificates then there may not be a straight forward way to accept them. In these cases, you can manually download a client ticket from Ignition and supply it to the OPC server in the appropriate manner.
Download a Client Certificate Manually
- Go to Config section in the Gateway Webpage.
- Select OPC UA > Certificate from the left side of the page. The Manage Certificates page is displayed.
- In the This Gateway tab, click the download link under Ignition OPC UA Client, and save the certificate somewhere to disk. This certificate is then supplied to your third-party OPC server in a way specific to that server. For more information, check the respective server's documentation.