$ openvpn --config client.ovpn
Wed Jan 17 12:21:48 2018 OpenVPN 2.3.10 x86_64-pc-linux-gnu [SSL (OpenSSL)] [LZO] [EPOLL] [PKCS11] [MH] [IPv6] built on Jun 22 2017
Wed Jan 17 12:21:48 2018 library versions: OpenSSL 1.0.2g  1 Mar 2016, LZO 2.08
Enter Auth Username: ****
Enter Auth Password: ******************
Wed Jan 17 12:22:02 2018 Socket Buffers: R=[212992->212992] S=[212992->212992]
Wed Jan 17 12:22:02 2018 failed to find GID for group nobody
Wed Jan 17 12:22:02 2018 Exiting due to fatal error