我在 Linux Ubuntu 18.04.6 LTS 上使用 OpenVPN，它已经正常运行了一年多，直到上周五它停止了工作。
这是我收到的 OpenVPN 日志消息：
sudo openvpn --config RDENFW-UDP4-1194-dchicco.ovpn
2022-04-11 09:52:55 Note: Treating option '--ncp-ciphers' as '--data-ciphers' (renamed in OpenVPN 2.5).
2022-04-11 09:52:55 DEPRECATED OPTION: --cipher set to 'AES-256-CBC' but missing in --data-ciphers (AES-256-GCM:AES-128-GCM). Future OpenVPN version will ignore --cipher for cipher negotiations. Add 'AES-256-CBC' to --data-ciphers or change --cipher 'AES-256-CBC' to --data-ciphers-fallback 'AES-256-CBC' to silence this warning.
2022-04-11 09:52:55 WARNING: file 'RDENFW-UDP4-1194-dchicco.p12' is group or others accessible
2022-04-11 09:52:55 OpenVPN 2.5.3 x86_64-pc-linux-gnu [SSL (OpenSSL)] [LZO] [LZ4] [EPOLL] [PKCS11] [MH/PKTINFO] [AEAD] built on Jun 17 2021
2022-04-11 09:52:55 library versions: OpenSSL 1.0.2n 7 Dec 2017, LZO 2.08
Enter Private Key Password: *********
2022-04-11 09:52:58 WARNING: this configuration may cache passwords in memory -- use the auth-nocache option to prevent this
2022-04-11 09:52:58 TCP/UDP: Preserving recently used remote address: [AF_INET]130.15.58.32:1194
2022-04-11 09:52:58 UDP link local (bound): [AF_INET][undef]:0
2022-04-11 09:52:58 UDP link remote: [AF_INET]130.15.58.32:1194
2022-04-11 09:52:58 [RDEN_OpenVPN_Server_Cert] Peer Connection Initiated with [AF_INET]130.15.58.32:1194
2022-04-11 09:52:59 Options error: Unrecognized option or missing or extra parameter(s) in [PUSH-OPTIONS]:4: block-outside-dns (2.5.3)
2022-04-11 09:52:59 TUN/TAP device tun1 opened
2022-04-11 09:52:59 /sbin/ip link set dev tun1 up mtu 1500
2022-04-11 09:52:59 /sbin/ip link set dev tun1 up
2022-04-11 09:52:59 /sbin/ip addr add dev tun1 local 10.251.251.70 peer 10.251.251.69
RTNETLINK answers: File exists
2022-04-11 09:52:59 ERROR: Linux route add command failed: external program exited with error status: 2
RTNETLINK answers: File exists
2022-04-11 09:52:59 ERROR: Linux route add command failed: external program exited with error status: 2
RTNETLINK answers: File exists
2022-04-11 09:52:59 ERROR: Linux route add command failed: external program exited with error status: 2
RTNETLINK answers: File exists
2022-04-11 09:52:59 ERROR: Linux route add command failed: external program exited with error status: 2
2022-04-11 09:52:59 Initialization Sequence Completed
文件内容如下ovpn.conf：
client
dev tun
remote-cert-tls server
cipher aes-256-cbc
pull
nobind
reneg-sec 0
resolv-retry infinite
verb 3
persist-key
persist-tun
remote-random
remote pool-1.prd.ca.toronto.ovpn.com 1194
remote pool-1.prd.ca.toronto.ovpn.com 1195
proto udp
mute-replay-warnings
replay-window 256
comp-lzo
auth-user-pass /etc/openvpn/credentials
ca /etc/openvpn/ovpn-ca.crt
tls-auth /etc/openvpn/ovpn-tls.key 1
log /tmp/openvpn.log
script-security 2
up /etc/openvpn/update-resolv-conf
down /etc/openvpn/update-resolv-conf
有什么办法可以解决这个问题吗？我已经尝试过重启电脑并运行命令，sudo ip link delete tun1但没有任何变化。我也研究了 AskUbuntu 上的其他答案，但没有找到与我的情况相关的任何内容。