[root certs]# systemctl status openvpn@server
● openvpn@server.service - OpenVPN Robust And Highly Flexible Tunneling Application On server
Loaded: loaded (/usr/lib/systemd/system/openvpn@.service; enabled; vendor preset: disabled)
Active: failed (Result: exit-code) since Sat 2018-06-02 22:03:07 CST; 14s ago
Main PID: 18893 (code=exited, status=1/FAILURE)
Status: "Pre-connection initialization successful"

Jun 02 22:03:07 iZ6we4m4as9i2suoroqnq4Z systemd[1]: Starting OpenVPN Robust And Highly Flexible Tunneling Application On server...
Jun 02 22:03:07 iZ6we4m4as9i2suoroqnq4Z systemd[1]: Started OpenVPN Robust And Highly Flexible Tunneling Application On server.
Jun 02 22:03:07 iZ6we4m4as9i2suoroqnq4Z systemd[1]: openvpn@server.service: main process exited, code=exited, status=1/FAILURE
Jun 02 22:03:07 iZ6we4m4as9i2suoroqnq4Z systemd[1]: Unit openvpn@server.service entered failed state.
Jun 02 22:03:07 iZ6we4m4as9i2suoroqnq4Z systemd[1]: openvpn@server.service failed.   

解决方案：

在server.conf 中 不要写入

local 192.168.1.168   #服务器IP