Appendix A.5.2. Configuring Fieldserver As Ssl/Tls Client - SMC Networks FieldServer QuickServer FS-QS-12 0 Series Startup Manual

Appendix A.5.2. Configuring FieldServer as SSL/TLS Client

The following Node configurations set the FieldServer to open a secure Modbus/TCP connection to
Server at IP Address 10.11.12.13 on port 1502.
Appendix A.5.2.1. Simple Secure Client Configuration
Add Remote_Node_TLS_Port parameter in the nodes section of the configuration file and set to a port
number between 1 – 65535.
Nodes
Node_Name , Node_ID , Protocol
PLC_11 , 11
The above configurations set the FieldServer to connect to a remote server but not request a server's
certificate for verification. This means the FieldServer end point communication will be encrypted but not
authenticated.
If requested by a remote server, the FieldServer will send an embedded self-signed certificate.
Appendix A.5.2.2. Limit Server Access
Add Validate_Server_Cert parameter to client node.
....... , Remote_Node_TLS_Port
........ , 1502
The above configuration sets the FieldServer to request and verify server's certificate against its internal
authority file before finalizing the connection. By default, this means the FieldServer will only establish
connections to other FieldServers.
.......
, Remote_Node_TLS_Port
........
, 1502
The above configuration sets the FieldServer to use a specified PEM file to allow custom server
connections.
Authority file is simply a collection of server certificates in PEM format. This file can be edited using any
text file editor (e.g notepad) then copy and paste public PEM formatted server certificate. Now
FieldServer will connect to server if it can find server's certificate in authority file.
NOTE: Cert_Authority_File is useful only if Validate_Client_Cert is set to 'Yes'.
To download Certificate to the FieldServer refer to Section .
Appendix A.5.2.3. Certificate Validation Options
Use the Check_Remote_Host element as described in Section .
Appendix A.5.2.4. Set up Client Certificate
Make sure the certificate is in PEM format. Otherwise, convert it to PEM format (reference the link below).
support.ssl.com/Knowledgebase/Article
Configure the FieldServer to use a custom certificate as shown below:
......... , Client_Cert_File
......... , my_client_cert.pem
, Adapter
, Modbus/TCP , N1
, Validate_Server_Cert
, Yes
, Validate_Server_Cert
, Yes
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QuickServer Start-Up Guide
, IP_Address , Remote_Node_TLS_Port
, 10.11.12.13 , 1502
, Cert_Authority_File
, my_authorized_servers.pem