新用户！刚刚安装了 Ubuntu 18.04.3 LTS
安装了 Openvpn，配置了客户端并使用以下命令安装网络管理器“nmcli”并尝试连接客户端。
抽出时间。
$ sudo apt-get install 网络管理器 网络管理器-openvpn
$ cd ~/
$ sudo nmcli 连接导入类型 openvpn 文件客户端.ovpn
$ nmcli 连接客户端
出现超时错误...为什么？
使用 dpkg -l 我得到了以下详细信息：
ii openvpn 2.4.4-2ubuntu1.3 amd64 virtual private network daemon
ii wpasupplicant 2:2.6-15ubuntu2.3 amd64 client support for WPA and WPA2 (IEEE 802.11i)
使用 grep -i vpn /var/log/syslog* 获得了 openvpn 日志的以下详细信息：
/var/log/syslog:Aug 12 07:40:35 syed007-K53SD openvpn[1702]: Initialization Sequence Completed
/var/log/syslog:Aug 12 08:41:26 syed007-K53SD gsd-housekeepin[3000]: Failed to enumerate children of >/var/tmp/systemd-private-4a81781c01ad49b6b3c36f8bbad324b7-openvpn-server@server.service-ScMdFg: Error opening directory '>/var/tmp/systemd-private-4a81781c01ad49b6b3c36f8bbad324b7-openvpn-server@server.service-ScMdFg': Permission denied
/var/log/syslog:Aug 12 08:41:26 syed007-K53SD gsd-housekeepin[3000]: Failed to enumerate children of /tmp/systemd-private-4a81781c01ad49b6b3c36f8bbad324b7-openvpn-server@server.service-jvwner: Error opening directory '/tmp/systemd-private-4a81781c01ad49b6b3c36f8bbad324b7-openvpn-server@server.service-jvwner': Permission denied
/var/log/syslog:Aug 12 15:45:25 syed007-K53SD systemd[1]: Starting openvpn-iptables.service...
/var/log/syslog:Aug 12 15:45:25 syed007-K53SD systemd[1]: Started openvpn-iptables.service.
/var/log/syslog:Aug 12 15:45:25 syed007-K53SD kernel: [ 8.245210] systemd[1]: Created slice system-openvpn\x2dserver.slice.
/var/log/syslog:Aug 12 15:45:30 syed007-K53SD systemd[1]: Starting OpenVPN service...
/var/log/syslog:Aug 12 15:45:30 syed007-K53SD systemd[1]: Started OpenVPN service.
/var/log/syslog:Aug 12 15:45:40 syed007-K53SD systemd[1]: Starting OpenVPN service for server...
/var/log/syslog:Aug 12 15:45:41 syed007-K53SD openvpn[1611]: OpenVPN 2.4.4 x86_64-pc-linux-gnu [SSL (OpenSSL)] [LZO] [LZ4] [EPOLL] [PKCS11] [MH/PKTINFO] [AEAD] built on May 14 2019
/var/log/syslog:Aug 12 15:45:41 syed007-K53SD openvpn[1611]: library versions: OpenSSL 1.1.1 11 Sep 2018, LZO 2.08
/var/log/syslog:Aug 12 15:45:41 syed007-K53SD systemd[1]: Started OpenVPN service for server.
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: Diffie-Hellman initialized with 2048 bit key
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: Outgoing Control Channel Authentication: Using 512 bit message hash 'SHA512' for HMAC authentication
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: Incoming Control Channel Authentication: Using 512 bit message hash 'SHA512' for HMAC authentication
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: TUN/TAP device tun0 opened
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: TUN/TAP TX queue length set to 100
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: do_ifconfig, tt->did_ifconfig_ipv6_setup=0
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: /sbin/ip link set dev tun0 up mtu 1500
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: /sbin/ip addr add dev tun0 10.8.0.1/24 broadcast 10.8.0.255
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: Could not determine IPv4/IPv6 protocol. Using AF_INET
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: Socket Buffers: R=[212992->212992] S=[212992->212992]
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: UDPv4 link local (bound): [AF_INET][undef]:1194
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: UDPv4 link remote: [AF_UNSPEC]
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: GID set to nogroup
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: UID set to nobody
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: MULTI: multi_init called, r=256 v=256
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: IFCONFIG POOL: base=10.8.0.2 size=252, ipv6=0
/var/log/syslog:Aug 12 15:45:42 syed007-K53SD openvpn[1611]: IFCONFIG POOL LIST
命令$ ls -al /etc/resolv.conf的结果如下：
lrwxrwxrwx 1 root root 39 Aug 2 18:12 /etc/resolv.conf -> ../run/systemd/resolve/stub-resolv.conf
命令 $ cat /etc/resolv.conf 给出以下输出：
nameserver 127.0.0.53
options edns0
命令 $ sudo openvpn client.ovpn 的结果如下：
Tue Aug 13 06:14:04 2019 Unrecognized option or missing or extra parameter(s) in client.ovpn:14: block-outside-dns (2.4.4)
Tue Aug 13 06:14:04 2019 OpenVPN 2.4.4 x86_64-pc-linux-gnu [SSL (OpenSSL)] [LZO] [LZ4] [EPOLL] [PKCS11] [MH/PKTINFO] [AEAD] built on May 14 2019
Tue Aug 13 06:14:04 2019 library versions: OpenSSL 1.1.1 11 Sep 2018, LZO 2.08
Tue Aug 13 06:14:04 2019 Outgoing Control Channel Authentication: Using 512 bit message hash 'SHA512' for HMAC authentication
Tue Aug 13 06:14:04 2019 Incoming Control Channel Authentication: Using 512 bit message hash 'SHA512' for HMAC authentication
Tue Aug 13 06:14:04 2019 TCP/UDP: Preserving recently used remote address: [AF_INET]201.0.111.11:1194
Tue Aug 13 06:14:04 2019 Socket Buffers: R=[212992->212992] S=[212992->212992]
Tue Aug 13 06:14:04 2019 UDP link local: (not bound)
Tue Aug 13 06:14:04 2019 UDP link remote: [AF_INET]201.0.111.11:1194
Tue Aug 13 06:15:04 2019 TLS Error: TLS key negotiation failed to occur within 60 seconds (check your network connectivity)
Tue Aug 13 06:15:04 2019 TLS Error: TLS handshake failed
Tue Aug 13 06:15:04 2019 SIGUSR1[soft,tls-error] received, process restarting
Tue Aug 13 06:15:04 2019 Restart pause, 5 second(s)
Tue Aug 13 06:15:09 2019 TCP/UDP: Preserving recently used remote address: [AF_INET]201.0.111.11:1194
Tue Aug 13 06:15:09 2019 Socket Buffers: R=[212992->212992] S=[212992->212992]
Tue Aug 13 06:15:09 2019 UDP link local: (not bound)
Tue Aug 13 06:15:09 2019 UDP link remote: [AF_INET]201.0.111.11:1194