Configure the communication settings for OPC UA Server

The communication settings for the OPC UA Server module are located in the Project Settings dialog box. These settings determine how the server will appear on the network, as well as how OPC UA clients may communicate with it. You need to review and configure these settings before project run time.

Before you begin this task, you should be familiar with the OPC United Architecture (OPC UA) specification and how OPC UA servers and clients communicate with each other. In particular, you should understand how servers and clients use certificates to identify each other and communicate securely.

To configure the communication settings for the OPC UA Server module:

1. On the Project tab of the ribbon, in the Settings group, click Communication.

   The Communication tab of the Project Settings dialog box is displayed.

   

2. In the Endpoint URL boxes, type the node name and port number for the OPC UA server endpoint.

   The default node name is [NodeName]. This is a special string that automatically gets the host name of the actual computer or device that hosts the project, so that you do not need to change the node name each time you download your project to another computer.

   The default port number is 48010, which is the standard port number for OPC UA communication.

   In most cases, you should keep the default node name and port number. If you think you need to change either of them, ask your network administrator.

3. In the Identity area, select the identity types that will be allowed to log on to the OPC UA server.

   You must select at least one of the available options. If you do not, the OPC UA Server Runtime task will not be able to start during project run time. The options are not exclusive; you can select more than one option.

   Option	Description
   Enable anonymous login	Allow clients to log on to the server without entering a username or password.
   Enable Username/Password	Require clients to enter a username and password that a match a user in your project's security system. This option is available only if the security system has been enabled.

4. In the Security Policies area, select the policies that the OPC UA server may use to communicate with OPC UA clients.

   In order for a server and client to communicate with each other, they must have at least one security policy in common.

   First, select the encryption types. You must select at least one of the available options. If you do not, the OPC UA Server Runtime task will not be able to start during project run time. The options are not exclusive; you can select more than one option.

   Option	Description
   None	Communication between server and client does not need to be encrypted.
   Basic256	The server will use and recognize 256-bit AES encryption. (This option is selected by default in new projects.)
   Basic128Rsa15	The server will use and recognize 128-bit AES encryption.

   Then, for each encryption type you have selected, select its messaging mode.

   Option	Description
   Sign	Messages between server and client must be signed.
   Sign and Encrypt	Messages between server and client must be signed and encrypted.
   Sign, Sign and Encrypt	Messages between server and client may be either signed, or signed and encrypted. (This option is selected by default in new projects.)

   For more information about these options and how the OPC UA clients might be configured, ask your network administrator.

5. In the Certificates area, review the information that will be included in the OPC UA server's self-signed certificate.

   This is the certificate that the server will present to clients in order to identify itself. It is signed by the software itself, as opposed to being signed by a Certificate Authority (CA).

   1. Click Self-Signed Certificate Information.

      The OPC UA Server Self-Signed Certificate Information dialog box is displayed.

      

   2. In the Common Name box, type the common name of the OPC UA server itself.

      This is the name that is broadcast to the discovery server and other OPC UA clients on the network. The default common name is [ServerName]. This is a special string that includes [NodeName] (see above), which automatically gets the host name of the actual computer or device that hosts the project. The value of [ServerName] is:

      StudioOpcUaServer@[NodeName]

   3. In the Machine box, type the name of the computer or device that will host the project runtime server.

      The default machine name is [NodeName] (see above).

   4. In the Organization, Organization Unit, Location Name, State/Province, and Country boxes, type the appropriate information for your project.

   5. In the Years Valid For box, type the number of years for which the certificate will be valid, starting from the date it is issued.

      The default number of years is 5. When a certificate expires, you must delete it and then issue a new one.

   6. In the IP Addresses box, type all of the addresses that may be used by the actual computer or device that will host the project and present this certificate.

      You may leave this box empty. Doing so will not prevent the server certificate from being issued or make it not valid.

   7. In the DNS Names box, type the names of the domain name servers that will administer the project runtime server.

      The default DNS name is [NodeName] (see above).

   8. Click Delete server certificate.

      This is to make sure the existing certificate (if any) is deleted from the project files, so that a new certificate can be issued with the updated information.

   9. Click OK to close the OPC UA Server Self-Signed Certificate Information dialog box.

      Note: The values of [ServerName] and [NodeName] are determined when the server certificate is issued, and the server certificate is issued when the project is run and the OPC UA Server Runtime task is started. As such, if you test your project on your development workstation, the certificate will be issued using the host name of that computer. You should delete the certificate — by clicking Delete server certificate — before you download your project to another computer. If you do not, you will need to manually delete the certificate files on that computer so that a new certificate can be issued with the correct information. For more information, see How to manage OPC UA Server during project run time.

6. If you want to accept the certificates of all OPC UA clients that try to connect to the OPC UA server, select Automatically trust client certificates.

   Note: The Automatically trust client certificates option is cleared by default, for security reasons. If you do not select this option, you will need to manually add client certificates to the server's "trusted" list. For more information, see How to manage OPC UA Server during project run time.

7. In the Stack trace level list, select the level of trace messages that you want to be saved in the OPC UA communication log.

   Option	Description
   Disabled	Logging is disabled for OPC UA communication; no messages will be saved in the communication log.
   Error	Critical issues that have caused OPC UA communication to fail. These issues must be resolved before communication can resume. (This level is selected by default in new projects.)
   Warning	Non-critical issues that affect runtime performance or might cause OPC UA communication to fail under other conditions. These issues should be resolved as soon as possible. This level includes Error (see above).
   Info	Informational messages generated by normal OPC UA communication. This level includes Error and Warning (see above).
   Verbose	All trace messages generated by the OPC UA communication stack. This can be extremely verbose, and it will generate a very large log file over time. Select this level only if you are troubleshooting serious issues.

8. Click OK to close the Project Settings dialog box.