使用单个公共 IP NIC 设置桥接 OpenVPN 服务器

Question 1

~~我认为桥接模式下 OpenVPN 不会分配 IP。因此您需要提供 DHCP 服务器来执行此操作。~~

仔细观察...这是我的想法。

我认为你已经到达tap0并eth0连接了桥梁br0？（brctl可以验证）

br0服务器上的 IP 不在 OpenVPN 子网内。

让我猜一下，eth0这是你的面向互联网的接口。你不需要这样做。不要放入eth0桥接器。

我猜你想启用广播，即设置桥接，这样所有 VPN 主机都可以相互广播。我还没有这样做，但所有 VPN 主机都应该能够在不eth0开启的情况下做到这一点br0。

您需要在服务器端使用 OpenVPN 桥接的原因是为了连接 LAN 和 VPN。如果这是 VPS，则听起来您背后没有 LAN，因此不需要桥接至另一个物理接口，也不会为您做任何事情。

Answer

~~我认为桥接模式下 OpenVPN 不会分配 IP。因此您需要提供 DHCP 服务器来执行此操作。~~

仔细观察...这是我的想法。

我认为你已经到达tap0并eth0连接了桥梁br0？（brctl可以验证）

br0服务器上的 IP 不在 OpenVPN 子网内。

让我猜一下，eth0这是你的面向互联网的接口。你不需要这样做。不要放入eth0桥接器。

我猜你想启用广播，即设置桥接，这样所有 VPN 主机都可以相互广播。我还没有这样做，但所有 VPN 主机都应该能够在不eth0开启的情况下做到这一点br0。

您需要在服务器端使用 OpenVPN 桥接的原因是为了连接 LAN 和 VPN。如果这是 VPS，则听起来您背后没有 LAN，因此不需要桥接至另一个物理接口，也不会为您做任何事情。

Question 2

我喜欢 OpenVPN 和我的 xUbuntu，第一次上手时学习曲线比较陡峭，但以下几件事可能会有所帮助...

OpenVPN 可以发出与服务器网络相同的 IP，您不必使用不同的范围。我所做的就是进入路由器的 DHCP 高级设置并告诉我的路由器不要发出 192.168.1.200 - 192.168.1.250。

然后，我将我的 OpenVPN 服务器设置为将 192.168.1.200 - 192.168.1.250 留作分配使用的 IP 池。

这最大限度地减少了对疯狂路由设置的需要，有时还会受到网络通信的限制[如果您忘记在一个客户端上设置路由，VPN 客户端可能无法看到它]，但使用与您的路由器相同的 IP 可将所有内容保留在相同的网络路由和子网内。

这是我的/etc/network/interfaces

# interfaces(5) file used by ifup(8) and ifdown(8)
# auto eth0
# iface eth0 inet dhcp
#
# The loopback network interface
auto lo
iface lo inet loopback

 auto br1
  iface br1 inet static
  bridge_ports eth0
  address 192.168.1.62
  netmask 255.255.255.0
  gateway 192.168.1.1
  dns-nameservers 208.67.222.222 192.168.1.1
  dns-search home
  dns-domain home

 auto eth0
 iface eth0 inet dhcp

DNS 搜索选项很不错，因为我在路由器中指定了 home 作为域，现在如果我从 *nix 客户端 ping router.home，它会回复，因为这是一个真正的完全合格的 DNS 条目。但这并不是让一切正常运行所必需的。

还要注意，无论你把它叫做 br0 还是 br1 都没有关系，我在设置时遇到了问题，并从 br0 移动到 br1，因为我正在处理一些事情，一旦我让它完全正常工作，它就在 br1 上，我不想搞砸成功 :-)

这是我的服务器配置[我删除了我的服务器子 IP 的确切 IP（无论您的 IP 是什么），我留下了所有注释和所有内容，以防万一它可以帮助某人：

#################################################
# 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 192.168.1.xx

# 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 123

# 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 tap0
;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 dh1024.pem 1024
# Substitute 2048 for 1024 if you are using
# 2048 bit keys. 
dh dh2048.pem

# 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 10.8.0.0 255.255.255.0

# 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 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 192.168.1.xx 255.255.255.0 192.168.1.200 192.168.1.254

# 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 \u201croute 192.168.1.1 255.255.255.0\u2033
;push "route 192.168.20.0 255.255.255.0"

# 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 192.168.1.1"
push "dhcp-option DNS 208.67.222.222"

# 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

# Select a cryptographic cipher.
# This config item must be copied to
# the client config file as well.
cipher BF-CBC        # Blowfish (default)
;cipher AES-128-CBC   # AES
;cipher DES-EDE3-CBC  # Triple-DES

# Enable compression on the VPN link.
# 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 30

# 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 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         openvpn.log
;log-append  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 5

# Silence repeating messages.  At most 20
# sequential messages of the same message
# category will be output to the log.
mute 20

## Bridge Scripts
up "/etc/openvpn/up.sh br1 tap0 1500"
down "/etc/openvpn/down.sh br1 tap0"
script-security 3

下面是我在 Windows 7 专业客户端上使用的示例工作客户端配置 [我再次清理了服务器的远程 IP 和端口 [或者您可以在此处使用 DynDNS 之类的 DNS，如果您没有静态 IP，它可以正常工作] 我还清理了我的密钥文件的名称：

# Specify that this is a client
client

# Bridge device setting
dev tap

# Host name and port for the server (default port is 1194)
# note: replace with the correct values your server set up
remote 111.222.333.444 123

# Client does not need to bind to a specific local port
nobind

# Keep trying to resolve the host name of OpenVPN server.
## The windows GUI seems to dislike the following rule. 
##You may need to comment it out.
resolv-retry infinite

# Preserve state across restarts
persist-key
persist-tun

# SSL/TLS parameters - files created previously
ca ca.crt
cert client.crt
key client.key

# Since we specified the tls-auth for server, we need it for the client
# note: 0 = server, 1 = client
tls-auth ta.key 1

# Specify same cipher as server
cipher BF-CBC

# Use compression
comp-lzo

# Log verbosity (to help if there are problems)
verb 3

我可以说我也使用名为 OpenVPN Settings 的 Android 客户端 [Android 的官方 OPENVPN 客户端无法处理桥接设置，我再说一遍，您需要一台 root 设备并安装 Play Store 上的 OpenVPN 设置] 和 Windows，并且我有一个用户使用 OSX 客户端，每个人都对结果非常满意。我需要一个桥接设置，因为我使用名为 Plex Media Server 的 SWEET 媒体服务器，它使用子网广播来宣传服务器，如果您无法获得广播，您就无法使用客户端 [他们也提供远程服务，但我是一个安全狂，宁愿不使用他们的安全加密连接服务，而是自己管理一切 :-D。

希望这些能对你有帮助:-D

我花费了大量的时间和精力来确定所有设置并使一切都令人满意，但最终的结果确实是值得的。

Answer