[SOLVED] Connected to a Server but no internet connection

Need help configuring your VPN? Just post here and you'll get that help.

Moderators: TinCanTech, TinCanTech, TinCanTech, TinCanTech, TinCanTech, TinCanTech

Forum rules
Please use the [oconf] BB tag for openvpn Configurations. See viewtopic.php?f=30&t=21589 for an example.
Post Reply
tappthedud
OpenVpn Newbie
Posts: 2
Joined: Sat Mar 02, 2024 3:16 pm

[SOLVED] Connected to a Server but no internet connection

Post by tappthedud » Sat Mar 02, 2024 3:48 pm

First, I would like to say that I have been looking on google and found OpenVPN as a solution to "How to borrow my public IP address to a friend remotely" query.

So, I downloaded OpenVPN & created keys for both me and my friend, following this tutorial: https://openvpn.net/community-resources ... ficate-key
(We are both on Windows 10)

I forwarded port 1194 TCP & UDP in my router and temporarily disabled windows firewall (just to exclude it as a potential cause).
We didn't change any of the default configs in the sample-config folder, except for specifying the remote host ip (obviously) in the client.ovpn and uncommenting this line:

Code: Select all

push "redirect-gateway def1 bypass-dhcp"
in server.ovpn.

My friend then connects to my server just fine, we both can see it in the logs but he loses access to the internet. Even a simple

Code: Select all

curl ifconfig.me
won't work. He has to disconnect to get his internet back. What, possibly, are we missing here? :?:

Code: Select all

C:\Program Files\OpenVPN\sample-config>openvpn server_org.ovpn
21:45:15 DEPRECATED OPTION: --cipher set to 'AES-256-CBC' but missing in --data-ciphers (AES-256-GCM:AES-128-GCM). OpenVPN ignores --cipher for cipher negotiations.
21:45:15 Note: dev-type not tun, disabling data channel offload.
21:45:15 OpenVPN 2.6.9 [git:v2.6.9/6640a10bf6d84eee] Windows [SSL (OpenSSL)] [LZO] [LZ4] [PKCS11] [AEAD] [DCO] built on Feb 12 2024
21:45:15 Windows version 10.0 (Windows 10 or greater), amd64 executable
21:45:15 library versions: OpenSSL 3.2.0 23 Nov 2023, LZO 2.10
21:45:15 DCO version: 1.0.0
21:45:15 NOTE: your local LAN uses the extremely common subnet address 192.168.0.x or 192.168.1.x.  Be aware that this might create routing conflicts if you connect to the VPN server from public locations such as internet cafes that use the same subnet.
21:45:15 Diffie-Hellman initialized with 2048 bit key
21:45:15 interactive service msg_channel=0
21:45:15 open_tun
21:45:15 tap-windows6 device [OpenVPN TAP-Windows6] opened
21:45:15 TAP-Windows Driver Version 9.26
21:45:15 Notified TAP-Windows driver to set a DHCP IP/netmask of 10.8.0.1/255.255.255.0 on interface {639345D1-E4BC-466E-93C4-FB98B098F37F} [DHCP-serv: 10.8.0.0, lease-time: 31536000]
21:45:15 Sleeping for 10 seconds...
21:45:25 Successful ARP Flush on interface [7] {639345D1-E4BC-466E-93C4-FB98B098F37F}
21:45:25 IPv4 MTU set to 1500 on interface 7 using SetIpInterfaceEntry()
21:45:25 Could not determine IPv4/IPv6 protocol. Using AF_INET6
21:45:25 Socket Buffers: R=[65536->65536] S=[65536->65536]
21:45:25 setsockopt(IPV6_V6ONLY=0)
21:45:25 UDPv6 link local (bound): [AF_INET6][undef]:1194
21:45:25 UDPv6 link remote: [AF_UNSPEC]
21:45:25 MULTI: multi_init called, r=256 v=256
21:45:25 IFCONFIG POOL IPv4: base=10.8.0.2 size=253
21:45:25 ifconfig_pool_read(), in='client1,10.8.0.4,'
21:45:25 succeeded -> ifconfig_pool_set(hand=2)
21:45:25 IFCONFIG POOL LIST
21:45:25 client1,10.8.0.4,
21:45:25 Initialization Sequence Completed
Pinging

C:\WINDOWS\system32>ping 10.8.0.6
Pinging 10.8.0.6 with 32 bytes of data:
Reply from 10.8.0.6: bytes=32 time<1ms TTL=128
Reply from 10.8.0.6: bytes=32 time<1ms TTL=128
Reply from 10.8.0.6: bytes=32 time<1ms TTL=128
Reply from 10.8.0.6: bytes=32 time<1ms TTL=128

C:\WINDOWS\system32>ping 10.8.0.1
Pinging 10.8.0.1 with 32 bytes of data:
Reply from 10.8.0.1: bytes=32 time=15ms TTL=128
Reply from 10.8.0.1: bytes=32 time=12ms TTL=128
Reply from 10.8.0.1: bytes=32 time=15ms TTL=128
Reply from 10.8.0.1: bytes=32 time=12ms TTL=128

Server Config

#################################################
# 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 1194

# 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

# 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 10.8.0.0 255.255.255.0

# 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 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 192.168.20.0 255.255.255.0"

# 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 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 tls-auth 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.
# 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

# 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 on non-Windows
# systems after creating a dedicated user.
;user openvpn
;group openvpn

# 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 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

Client Config

##############################################
# 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 xx.xxx.xx.xxx 1194
;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 openvpn
;group openvpn

# 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 client.crt
key client.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-auth ta.key 1

# 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-CBC

# 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.
verb 3

# Silence repeating messages
;mute 20

Code: Select all

Unknown adapter OpenVPN Data Channel Offload:

   Connection-specific DNS Suffix  . :
   Description . . . . . . . . . . . : OpenVPN Data Channel Offload
   Physical Address. . . . . . . . . :
   DHCP Enabled. . . . . . . . . . . : No
   Autoconfiguration Enabled . . . . : Yes
   Link-local IPv6 Address . . . . . : xxxxxx(Preferred)
   IPv4 Address. . . . . . . . . . . : 10.8.0.6(Preferred)
   Subnet Mask . . . . . . . . . . . : 255.255.255.252
   Default Gateway . . . . . . . . . :
   DHCPv6 IAID . . . . . . . . . . . : 7425782xx
   DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-26-25-DD-6F-00-D8-61-A5-xx-xx
   DNS Servers . . . . . . . . . . . : fec0:0:0:ffff::1%1
                                       fec0:0:0:ffff::2%1
                                       fec0:0:0:ffff::3%1
   NetBIOS over Tcpip. . . . . . . . : Enabled

Image

We also tried:
Try pinging google.com and 8.8.8.8. If the first doesn't resolve but the second does respond, then it's a DNS issue.
but both could not be reached.
//edit
ICS - "internet connection sharing". I enabled it for "OpenVPN Tap-Windows6" network adapter, choosing 'Ethernet' from the dropdown list but this immediately disconnects ME from the internet. So when my friend connects, he does not have internet access either.


P.S. We are very inexperienced in this field, but are 'computer guys' otherwise. Just not in the networking :P
Last edited by tappthedud on Sun Mar 03, 2024 10:54 am, edited 1 time in total.

tappthedud
OpenVpn Newbie
Posts: 2
Joined: Sat Mar 02, 2024 3:16 pm

Re: Connected to a Server but no internet connection

Post by tappthedud » Sun Mar 03, 2024 10:52 am

SOLVED!

This is what I had to do in order for my friend to connect:
1. Enable the following services in services.msc:
- Internet Connection Sharing (ICS)
- Routing and Remote Access
2. Enable ICS in the main internet adapter (in my case it's 'Ethernet'):
Image
3. In regedit, go to:

Code: Select all

Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
and change 'IPEnableRouter' value from 0 to 1.
4. Port forward 1194 & allow openvpn through windows firewall.
5. Use the following server and client configs:
Notice the line 'dev-node TAP' in Client Config and then look at the picture above. TAP is the name of the adapter, you can rename it to whatever you want in the Network control panel on Windows.
Client Config

##############################################
# 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 TAP

# 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 xx.xx.xxx.xxx 1194
;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 openvpn
;group openvpn

# 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 client1.crt
key client1.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-auth ta.key 1

# 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-CBC

# 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.
verb 3

# Silence repeating messages
;mute 20

Server Config

port 1194
proto udp
dev tap
ca ca.crt
cert server.crt
key server.key
dh dh2048.pem
tls-auth ta.key 0
server 10.8.0.0 255.255.255.0
ifconfig-pool-persist ipp.txt
push "redirect-gateway def1 bypass-dhcp"
push "dhcp-option DNS 8.8.8.8"
push "dhcp-option DNS 8.8.4.4"
keepalive 10 120
cipher AES-256-CBC
comp-lzo
persist-key
persist-tun
status openvpn-status.log
verb 3
explicit-exit-notify 1


Final note, should the client get an error like "Route: Waiting for TUN/TAP interface to come up" then just keep trying while also switching 'dev tun' and 'dev tap' on and off. Finally, if it still doesn't work, both server and clients should restart PCs, it helped in our case.

tytogsm
OpenVpn Newbie
Posts: 3
Joined: Wed Mar 13, 2024 12:07 pm

Re: [SOLVED] Connected to a Server but no internet connection

Post by tytogsm » Sun Mar 24, 2024 8:55 pm

Thank you very much for the solution. I couldn't find the answer anywhere and in the end it was solved. In my case I opted for "dev tun" because iPhone do not support tap.

thank you very much again

Post Reply