我正在努力让我的 openVPN 2.5.5 在 Ubuntu 22.04 上运行。长话短说：
- 我的服务器已经运行多年（最近更新到 Ubuntu 22.04）
- 我有其他客户端正确连接（Windows 10、11、Android，没有其他 Ubuntu 客户端）
- 我刚刚安装了 Ubuntu 22.04，需要将其作为服务连接到我的 VPN
- 如果我将所有 conf/certificates 设置为 /etc/openvpn 并使用 sudo openvpn myfile.conf，VPN 似乎会初始化，但流量不会路由到 tun0，因此什么都不起作用。
- 如果我手动添加路线，效果很好
- 如果我在 gnome gui 中使用相同的配置（通过直接打开配置文件），也可以正常工作，无需稍后添加路线！
- 删除服务器上推送的路由只会消除客户端日志中的相关错误消息，但 10.23.32.0/24 流量仍未路由到 tun0
今天尝试了很多方法，并在论坛上阅读了很多资料，但到目前为止没有任何进展。
任何想法 ？
谢谢 ！
钢筋混凝土
配置
服务器配置文件
#################################################
# Sample OpenVPN 2.0 config file for #
# multi-client server. #
# #
# This file is for the server side #
# of a many-clients <-> one-server #
# OpenVPN configuration. #
# #
# OpenVPN also supports #
# single-machine <-> single-machine #
# configurations (See the Examples page #
# on the web site for more info). #
# #
# This config should work on Windows #
# or Linux/BSD systems. Remember on #
# Windows to quote pathnames and use #
# double backslashes, e.g.: #
# "C:\\Program Files\\OpenVPN\\config\\foo.key" #
# #
# Comments are preceded with '#' or ';' #
#################################################
# Which local IP address should OpenVPN
# listen on? (optional)
;local a.b.c.d
# Which TCP/UDP port should OpenVPN listen on?
# If you want to run multiple OpenVPN instances
# on the same machine, use a different port
# number for each one. You will need to
# open up this port on your firewall.
port 21994
# TCP or UDP server?
;proto tcp
proto udp
# "dev tun" will create a routed IP tunnel,
# "dev tap" will create an ethernet tunnel.
# Use "dev tap0" if you are ethernet bridging
# and have precreated a tap0 virtual interface
# and bridged it with your ethernet interface.
# If you want to control access policies
# over the VPN, you must create firewall
# rules for the the TUN/TAP interface.
# On non-Windows systems, you can give
# an explicit unit number, such as tun0.
# On Windows, use "dev-node" for this.
# On most systems, the VPN will not function
# unless you partially or fully disable
# the firewall for the TUN/TAP interface.
;dev tap
dev tun
# Windows needs the TAP-Win32 adapter name
# from the Network Connections panel if you
# have more than one. On XP SP2 or higher,
# you may need to selectively disable the
# Windows firewall for the TAP adapter.
# Non-Windows systems usually don't need this.
;dev-node MyTap
# SSL/TLS root certificate (ca), certificate
# (cert), and private key (key). Each client
# and the server must have their own cert and
# key file. The server and all clients will
# use the same ca file.
#
# See the "easy-rsa" directory for a series
# of scripts for generating RSA certificates
# and private keys. Remember to use
# a unique Common Name for the server
# and each of the client certificates.
#
# Any X509 key management system can be used.
# OpenVPN can also use a PKCS #12 formatted key file
# (see "pkcs12" directive in man page).
ca ca.crt
cert server.crt
key server.key # This file should be kept secret
# Diffie hellman parameters.
# Generate your own with:
# openssl dhparam -out dh2048.pem 2048
;dh dh2048.pem
dh none
# Network topology
# Should be subnet (addressing via IP)
# unless Windows clients v2.0.9 and lower have to
# be supported (then net30, i.e. a /30 per client)
# Defaults to net30 (not recommended)
topology subnet
# Configure server mode and supply a VPN subnet
# for OpenVPN to draw client addresses from.
# The server will take 10.8.0.1 for itself,
# the rest will be made available to clients.
# Each client will be able to reach the server
# on 10.8.0.1. Comment this line out if you are
# ethernet bridging. See the man page for more info.
server 10.23.32.0 255.255.255.0
# Maintain a record of client <-> virtual IP address
# associations in this file. If OpenVPN goes down or
# is restarted, reconnecting clients can be assigned
# the same virtual IP address from the pool that was
# previously assigned.
ifconfig-pool-persist /var/log/openvpn/ipp.txt
# Configure server mode for ethernet bridging.
# You must first use your OS's bridging capability
# to bridge the TAP interface with the ethernet
# NIC interface. Then you must manually set the
# IP/netmask on the bridge interface, here we
# assume 10.8.0.4/255.255.255.0. Finally we
# must set aside an IP range in this subnet
# (start=10.8.0.50 end=10.8.0.100) to allocate
# to connecting clients. Leave this line commented
# out unless you are ethernet bridging.
;server-bridge 10.8.0.4 255.255.255.0 10.8.0.50 10.8.0.100
# Configure server mode for ethernet bridging
# using a DHCP-proxy, where clients talk
# to the OpenVPN server-side DHCP server
# to receive their IP address allocation
# and DNS server addresses. You must first use
# your OS's bridging capability to bridge the TAP
# interface with the ethernet NIC interface.
# Note: this mode only works on clients (such as
# Windows), where the client-side TAP adapter is
# bound to a DHCP client.
;server-bridge
# Push routes to the client to allow it
# to reach other private subnets behind
# the server. Remember that these
# private subnets will also need
# to know to route the OpenVPN client
# address pool (10.8.0.0/255.255.255.0)
# back to the OpenVPN server.
;push "route 192.168.10.0 255.255.255.0"
push "route 192.168.62.0 255.255.255.0"
# To assign specific IP addresses to specific
# clients or if a connecting client has a private
# subnet behind it that should also have VPN access,
# use the subdirectory "ccd" for client-specific
# configuration files (see man page for more info).
# EXAMPLE: Suppose the client
# having the certificate common name "Thelonious"
# also has a small subnet behind his connecting
# machine, such as 192.168.40.128/255.255.255.248.
# First, uncomment out these lines:
client-config-dir ccd
;route 192.168.40.128 255.255.255.248
# Then create a file ccd/Thelonious with this line:
# iroute 192.168.40.128 255.255.255.248
# This will allow Thelonious' private subnet to
# access the VPN. This example will only work
# if you are routing, not bridging, i.e. you are
# using "dev tun" and "server" directives.
# EXAMPLE: Suppose you want to give
# Thelonious a fixed VPN IP address of 10.9.0.1.
# First uncomment out these lines:
;client-config-dir ccd
;route 10.9.0.0 255.255.255.252
# Then add this line to ccd/Thelonious:
# ifconfig-push 10.9.0.1 10.9.0.2
# Suppose that you want to enable different
# firewall access policies for different groups
# of clients. There are two methods:
# (1) Run multiple OpenVPN daemons, one for each
# group, and firewall the TUN/TAP interface
# for each group/daemon appropriately.
# (2) (Advanced) Create a script to dynamically
# modify the firewall in response to access
# from different clients. See man
# page for more info on learn-address script.
;learn-address ./script
# If enabled, this directive will configure
# all clients to redirect their default
# network gateway through the VPN, causing
# all IP traffic such as web browsing and
# and DNS lookups to go through the VPN
# (The OpenVPN server machine may need to NAT
# or bridge the TUN/TAP interface to the internet
# in order for this to work properly).
;push "redirect-gateway def1 bypass-dhcp"
# Certain Windows-specific network settings
# can be pushed to clients, such as DNS
# or WINS server addresses. CAVEAT:
# http://openvpn.net/faq.html#dhcpcaveats
# The addresses below refer to the public
# DNS servers provided by opendns.com.
;push "dhcp-option DNS 208.67.222.222"
;push "dhcp-option DNS 208.67.220.220"
# Uncomment this directive to allow different
# clients to be able to "see" each other.
# By default, clients will only see the server.
# To force clients to only see the server, you
# will also need to appropriately firewall the
# server's TUN/TAP interface.
client-to-client
# Uncomment this directive if multiple clients
# might connect with the same certificate/key
# files or common names. This is recommended
# only for testing purposes. For production use,
# each client should have its own certificate/key
# pair.
#
# IF YOU HAVE NOT GENERATED INDIVIDUAL
# CERTIFICATE/KEY PAIRS FOR EACH CLIENT,
# EACH HAVING ITS OWN UNIQUE "COMMON NAME",
# UNCOMMENT THIS LINE OUT.
;duplicate-cn
# The keepalive directive causes ping-like
# messages to be sent back and forth over
# the link so that each side knows when
# the other side has gone down.
# Ping every 10 seconds, assume that remote
# peer is down if no ping received during
# a 120 second time period.
keepalive 10 120
# For extra security beyond that provided
# by SSL/TLS, create an "HMAC firewall"
# to help block DoS attacks and UDP port flooding.
#
# Generate with:
# openvpn --genkey --secret ta.key
#
# The server and each client must have
# a copy of this key.
# The second parameter should be '0'
# on the server and '1' on the clients.
;tls-auth ta.key 0 # This file is secret
tls-crypt ta.key
# Select a cryptographic cipher.
# This config item must be copied to
# the client config file as well.
# Note that v2.4 client/server will automatically
# negotiate AES-256-GCM in TLS mode.
# See also the ncp-cipher option in the manpage
;cipher AES-256-CBC
cipher AES-256-GCM
auth SHA256
# Enable compression on the VPN link and push the
# option to the client (v2.4+ only, for earlier
# versions see below)
;compress lz4-v2
;push "compress lz4-v2"
# For compression compatible with older clients use comp-lzo
# If you enable it here, you must also
# enable it in the client config file.
;comp-lzo
# The maximum number of concurrently connected
# clients we want to allow.
;max-clients 100
# It's a good idea to reduce the OpenVPN
# daemon's privileges after initialization.
#
# You can uncomment this out on
# non-Windows systems.
user nobody
group nogroup
# The persist options will try to avoid
# accessing certain resources on restart
# that may no longer be accessible because
# of the privilege downgrade.
persist-key
persist-tun
# Output a short status file showing
# current connections, truncated
# and rewritten every minute.
status /var/log/openvpn/openvpn-status.log
# By default, log messages will go to the syslog (or
# on Windows, if running as a service, they will go to
# the "\Program Files\OpenVPN\log" directory).
# Use log or log-append to override this default.
# "log" will truncate the log file on OpenVPN startup,
# while "log-append" will append to it. Use one
# or the other (but not both).
;log /var/log/openvpn/openvpn.log
;log-append /var/log/openvpn/openvpn.log
# Set the appropriate level of log
# file verbosity.
#
# 0 is silent, except for fatal errors
# 4 is reasonable for general usage
# 5 and 6 can help to debug connection problems
# 9 is extremely verbose
verb 3
# Silence repeating messages. At most 20
# sequential messages of the same message
# category will be output to the log.
;mute 20
# Notify the client that when the server restarts so it
# can automatically reconnect.
explicit-exit-notify 1
客户端_unix.conf
##############################################
# Sample client-side OpenVPN 2.0 config file #
# for connecting to multi-client server. #
# #
# This configuration can be used by multiple #
# clients, however each client should have #
# its own cert and key files. #
# #
# On Windows, you might want to rename this #
# file so it has a .ovpn extension #
##############################################
# Specify that we are a client and that we
# will be pulling certain config file directives
# from the server.
client
# Use the same setting as you are using on
# the server.
# On most systems, the VPN will not function
# unless you partially or fully disable
# the firewall for the TUN/TAP interface.
;dev tap
dev tun
# Windows needs the TAP-Win32 adapter name
# from the Network Connections panel
# if you have more than one. On XP SP2,
# you may need to disable the firewall
# for the TAP adapter.
;dev-node MyTap
# Are we connecting to a TCP or
# UDP server? Use the same setting as
# on the server.
;proto tcp
proto udp
# The hostname/IP and port of the server.
# You can have multiple remote entries
# to load balance between the servers.
remote my_server_name_here.com 21994
;remote my-server-2 1194
# Choose a random host from the remote
# list for load-balancing. Otherwise
# try hosts in the order specified.
;remote-random
# Keep trying indefinitely to resolve the
# host name of the OpenVPN server. Very useful
# on machines which are not permanently connected
# to the internet such as laptops.
resolv-retry infinite
# Most clients don't need to bind to
# a specific local port number.
nobind
# Downgrade privileges after initialization (non-Windows only)
;user nobody --> will adjust when OK
;group nobody --> will adjust when OK
# Try to preserve some state across restarts.
persist-key
persist-tun
# If you are connecting through an
# HTTP proxy to reach the actual OpenVPN
# server, put the proxy server/IP and
# port number here. See the man page
# if your proxy server requires
# authentication.
;http-proxy-retry # retry on connection failures
;http-proxy [proxy server] [proxy port #]
# Wireless networks often produce a lot
# of duplicate packets. Set this flag
# to silence duplicate packet warnings.
;mute-replay-warnings
# SSL/TLS parms.
# See the server config file for more
# description. It's best to use
# a separate .crt/.key file pair
# for each client. A single ca
# file can be used for all clients.
ca ca.crt
cert my_certificate.crt
key my_key.key
# Verify server certificate by checking that the
# certificate has the correct key usage set.
# This is an important precaution to protect against
# a potential attack discussed here:
# http://openvpn.net/howto.html#mitm
#
# To use this feature, you will need to generate
# your server certificates with the keyUsage set to
# digitalSignature, keyEncipherment
# and the extendedKeyUsage to
# serverAuth
# EasyRSA can do this for you.
remote-cert-tls server
# If a tls-auth key is used on the server
# then every client must also have the key.
tls-crypt ta.key
# Select a cryptographic cipher.
# If the cipher option is used on the server
# then you must also specify it here.
# Note that v2.4 client/server will automatically
# negotiate AES-256-GCM in TLS mode.
# See also the data-ciphers option in the manpage
cipher AES-256-GCM
auth SHA256
# Enable compression on the VPN link.
# Don't enable this unless it is also
# enabled in the server config file.
#comp-lzo
# Set log file verbosity.
log /etc/client/mylog.log
verb 4
# Silence repeating messages
;mute 20
key-direction 1
openvpn 客户端日志（详细 4）
2022-08-21 20:45:01 us=612113 OpenVPN 2.5.5 x86_64-pc-linux-gnu [SSL (OpenSSL)] [LZO] [LZ4] [EPOLL] [PKCS11] [MH/PKTINFO] [AEAD] built on Mar 22 2022
2022-08-21 20:45:01 us=612173 library versions: OpenSSL 3.0.2 15 Mar 2022, LZO 2.10
2022-08-21 20:45:01 us=627841 Outgoing Control Channel Encryption: Cipher 'AES-256-CTR' initialized with 256 bit key
2022-08-21 20:45:01 us=627925 Outgoing Control Channel Encryption: Using 256 bit message hash 'SHA256' for HMAC authentication
2022-08-21 20:45:01 us=627960 Incoming Control Channel Encryption: Cipher 'AES-256-CTR' initialized with 256 bit key
2022-08-21 20:45:01 us=627998 Incoming Control Channel Encryption: Using 256 bit message hash 'SHA256' for HMAC authentication
2022-08-21 20:45:01 us=628199 Control Channel MTU parms [ L:1621 D:1156 EF:94 EB:0 ET:0 EL:3 ]
2022-08-21 20:45:01 us=651688 Data Channel MTU parms [ L:1621 D:1450 EF:121 EB:406 ET:0 EL:3 ]
2022-08-21 20:45:01 us=651810 Local Options String (VER=V4): 'V4,dev-type tun,link-mtu 1549,tun-mtu 1500,proto UDPv4,keydir 1,cipher AES-256-GCM,auth [null-digest],keysize 256,key-method 2,tls-client'
2022-08-21 20:45:01 us=651833 Expected Remote Options String (VER=V4): 'V4,dev-type tun,link-mtu 1549,tun-mtu 1500,proto UDPv4,keydir 0,cipher AES-256-GCM,auth [null-digest],keysize 256,key-method 2,tls-server'
2022-08-21 20:45:01 us=651865 TCP/UDP: Preserving recently used remote address: [AF_INET]XXX.XXX.XXX.XXX:21994
2022-08-21 20:45:01 us=651918 Socket Buffers: R=[212992->212992] S=[212992->212992]
2022-08-21 20:45:01 us=651941 UDP link local: (not bound)
2022-08-21 20:45:01 us=651965 UDP link remote: [AF_INET]XXX.XXX.XXX.XXX:21994
2022-08-21 20:45:01 us=654523 TLS: Initial packet from [AF_INET]XXX.XXX.XXX.XXX:21994, sid=04ecd3ce 818d1abc
2022-08-21 20:45:01 us=666165 VERIFY OK: depth=1, CN=Easy-RSA CA
2022-08-21 20:45:01 us=666597 VERIFY KU OK
2022-08-21 20:45:01 us=666625 Validating certificate extended key usage
2022-08-21 20:45:01 us=666647 ++ Certificate has EKU (str) TLS Web Server Authentication, expects TLS Web Server Authentication
2022-08-21 20:45:01 us=666668 VERIFY EKU OK
2022-08-21 20:45:01 us=666688 VERIFY OK: depth=0, CN=my_server
2022-08-21 20:45:01 us=684935 Control Channel: TLSv1.3, cipher TLSv1.3 TLS_AES_256_GCM_SHA384, peer certificate: 384 bit EC, curve secp384r1, signature: RSA-SHA256
2022-08-21 20:45:01 us=685040 [my_server] Peer Connection Initiated with [AF_INET]XXX.XXX.XXX.XXX:21994
2022-08-21 20:45:01 us=687068 PUSH: Received control message: 'PUSH_REPLY,route 192.168.62.0 255.255.255.0,route-gateway 10.23.32.1,topology subnet,ping 10,ping-restart 120,ifconfig 10.23.32.33 255.255.255.255,peer-id 0,cipher AES-256-GCM'
2022-08-21 20:45:01 us=687292 OPTIONS IMPORT: timers and/or timeouts modified
2022-08-21 20:45:01 us=687323 OPTIONS IMPORT: --ifconfig/up options modified
2022-08-21 20:45:01 us=687350 OPTIONS IMPORT: route options modified
2022-08-21 20:45:01 us=687377 OPTIONS IMPORT: route-related options modified
2022-08-21 20:45:01 us=687404 OPTIONS IMPORT: peer-id set
2022-08-21 20:45:01 us=687430 OPTIONS IMPORT: adjusting link_mtu to 1624
2022-08-21 20:45:01 us=687457 OPTIONS IMPORT: data channel crypto options modified
2022-08-21 20:45:01 us=687733 Outgoing Data Channel: Cipher 'AES-256-GCM' initialized with 256 bit key
2022-08-21 20:45:01 us=687779 Incoming Data Channel: Cipher 'AES-256-GCM' initialized with 256 bit key
2022-08-21 20:45:01 us=687845 net_route_v4_best_gw query: dst 0.0.0.0
2022-08-21 20:45:01 us=688070 net_route_v4_best_gw result: via 192.168.62.1 dev enp2s0
2022-08-21 20:45:01 us=688163 ROUTE_GATEWAY 192.168.62.1/255.255.255.0 IFACE=enp2s0 HWADDR=70:85:c2:01:ec:6f
2022-08-21 20:45:01 us=690329 TUN/TAP device tun0 opened
2022-08-21 20:45:01 us=690421 do_ifconfig, ipv4=1, ipv6=0
2022-08-21 20:45:01 us=690511 net_iface_mtu_set: mtu 1500 for tun0
2022-08-21 20:45:01 us=690694 net_iface_up: set tun0 up
2022-08-21 20:45:01 us=691455 net_addr_v4_add: 10.23.32.33/32 dev tun0
2022-08-21 20:45:01 us=691891 net_route_v4_add: 192.168.62.0/24 via 10.23.32.1 dev [NULL] table 0 metric -1
2022-08-21 20:45:01 us=692047 sitnl_send: rtnl: generic error (-101): Network is unreachable
2022-08-21 20:45:01 us=692119 ERROR: Linux route add command failed
2022-08-21 20:45:01 us=692192 WARNING: this configuration may cache passwords in memory -- use the auth-nocache option to prevent this
2022-08-21 20:45:01 us=692255 Initialization Sequence Completed
journalctl -u 网络管理器.服务
août 21 20:45:01 my_client NetworkManager[643]: <info> [1661107501.6931] manager: (tun0): new Tun device (/org/freedesktop/NetworkManager/Devices/4)
août 21 20:45:01 my_client NetworkManager[643]: <info> [1661107501.7243] device (tun0): state change: unmanaged -> unavailable (reason 'connection-assumed', sys-iface-state: 'external')
août 21 20:45:01 my_client NetworkManager[643]: <info> [1661107501.7268] device (tun0): state change: unavailable -> disconnected (reason 'connection-assumed', sys-iface-state: 'external')
août 21 20:45:01 my_client NetworkManager[643]: <info> [1661107501.7284] device (tun0): Activation: starting connection 'tun0' (342de6b0-69e3-4dec-99bd-535492a1f413)
août 21 20:45:01 my_client NetworkManager[643]: <info> [1661107501.7287] device (tun0): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'external')
août 21 20:45:01 my_client NetworkManager[643]: <info> [1661107501.7292] device (tun0): state change: prepare -> config (reason 'none', sys-iface-state: 'external')
août 21 20:45:01 my_client NetworkManager[643]: <info> [1661107501.7296] device (tun0): state change: config -> ip-config (reason 'none', sys-iface-state: 'external')
août 21 20:45:01 my_client NetworkManager[643]: <info> [1661107501.7300] device (tun0): state change: ip-config -> ip-check (reason 'none', sys-iface-state: 'external')
août 21 20:45:01 my_client NetworkManager[643]: <info> [1661107501.7648] device (tun0): state change: ip-check -> secondaries (reason 'none', sys-iface-state: 'external')
août 21 20:45:01 my_client NetworkManager[643]: <info> [1661107501.7652] device (tun0): state change: secondaries -> activated (reason 'none', sys-iface-state: 'external')
août 21 20:45:01 my_client NetworkManager[643]: <info> [1661107501.7666] device (tun0): Activation: successful, device activated.
网际协议连接
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enp2s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000
link/ether XX:XX:XX:XX:XX:XX brd ff:ff:ff:ff:ff:ff
4: tun0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UNKNOWN mode DEFAULT group default qlen 500
link/none
ip route（缺少路由 10.23.32.0/24 dev tun0，以及服务器推送的路由）
default via 192.168.62.1 dev enp2s0 proto dhcp metric 100
169.254.0.0/16 dev enp2s0 scope link metric 1000
192.168.62.0/24 dev enp2s0 proto kernel scope link src 192.168.62.111 metric 100
答案1
我不知道您的方法为何不起作用，但看起来您使用的是旧的、预 systemd 的 OpenVPN 启动方式。如果您使用 systemd 方式启动客户端，您的方案肯定有效。
答案2
服务器配置文件中由“client-config-dir ccd”调用的此客户端的配置错误。现在它可以正常工作了！