In OpenBSD, you can restart the networking service using the sh /etc/netstart command. This command will restart the networking service and apply any changes made to the network configuration.
Keep in mind that this command will only restart the networking service. If you have made changes to the network configuration, such as adding or modifying network interfaces or modifying routing tables, you will need to apply those changes using the appropriate commands or configuration files.
For example, to add a new network interface, you can use the ifconfig command. To modify the routing table, you can use the route command. Consult the OpenBSD documentation for more information on these commands and how to configure networking in OpenBSD.
Note that you may need to run the sh /etc/netstart command as the root user or with superuser privileges in order to restart the networking service.
Keep in mind that these are just general steps, and your specific configuration may vary depending on your system's setup. Consult the OpenBSD documentation for more detailed information.