Siemens SIMATIC S7-400 Operating Instructions Manual page 75

You export the certificate of the CP for communications partners from third-party vendors in
much the same way as when importing (see above). Follow the steps outlined below:
1. In the STEP 7 project open the global certificate manager:
Global security settings > Certificate manager
2. Open the "Device certificates" tab.
3. In the table select the row with the required certificate (here the OPC UA certificate) and
select the shortcut menu "Export".
4. Save the certificate in the file system of the PC of the connected ES.
Now you can transfer the exported certificate of the CP to the system of the third-party
vendor.
Certificate for logging server
If you use a logging server in your system, export the SSL certificate for the authentication of
the CP on the server.
CP as UA server: The communications partner (client) requires a certificate
If you use the CP as an OPC UA server and leave the security functions disable, check
whether the UA clients you are using demand a certificate. If the communications partner
(client) demands a certificate, you will need to enable the security functions of the CP in
STEP 7.
CP as UA client: Communications partner (server) without turning off the certificate blocking list
If you configure the CP as OPC UA client without security functions the CP does not receive
a certificate. If the CP as client is to to communicate with a server, on which the certificate
blocking list cannot be turned off, no connection will be established. In this case you need to
generate a self-signed certificate for the CP in STEP 7
Change certificate: Subject Alternative Name
STEP 7 adopts the properties "DNS name", "IP address", and "URI" from the parameter
"Subject Alternative Name" (Windows: "Alternative applicant name") from the STEP 7
configuration data.
You can change this parameter of an OPC UA certificate in the certificate manager of the
global security settings. To do this, select the OPC UA certificate in the table of device
certificates and call the shortcut menu "Renew". Properties of the parameter "Subject
Alternative Namer" changed in STEP 7 are not adopted by the STEP 7 project.
CP 443-1 OPC UA
Operating Instructions, 01/2017, C79000-G8976-C427-02
4.8 Configuration of the CP in STEP 7 Professional
Configuration and operation
75