VPN Server cannot ping clients

[deleted]

Hello,

I have configured my VPN server successfully and can connect. Also I made a Routing Rule to be able to talk with the network behind the VPN Server, my LAN.
From my Clients I can ping the LAN peers successfully and can open their services. Anyhow I cannot ping the VPN Clients from neither the VPN Server nor from the LAN Peers.
I am not that in Linux, but I guess I have not activated a Firewall:

# iptables --list
Chain INPUT (policy ACCEPT)
target prot opt source destination

Chain FORWARD (policy ACCEPT)
target prot opt source destination

Chain OUTPUT (policy ACCEPT)
target prot opt source destination

Does anyone have an idea?

Thanks
Peter

Pippin

It's in the howto:
https://community.openvpn.net/openvpn/wiki/HOWTO#ExpandingthescopeoftheVPNtoincludeadditionalmachinesoneithertheclientorserversubnet.

[deleted]

I am not sure, are the clients connected directly to the VPN Server additional clients? I Thought this only needs to be done if I want to reach peers behind the VPN Client

Pippin

pett1 wrote I Thought this only needs to be done if I want to reach peers behind the VPN Client

pett1 wrote I cannot ping the VPN Clients from neither the VPN Server nor from the LAN Peers

Which client IP are you trying to ping? The LAN IP or the tunnel IP?
Did you deactivate the client firewall?
Once you have done ^^^ try ping from the server to client on both IP.

And provide:
https://forums.openvpn.net/viewtopic.php?t=22603

Edit:
Also look at the picture here:
https://community.openvpn.net/openvpn/wiki/AvoidRoutingConflicts

[deleted]

I AM using the Community Version

Here my Server.conf:

# Which local IP address should OpenVPN
# listen on? (optional)
;local 192.168.x.x

port xxx

# TCP or UDP server?
;proto tcp
proto udp

;dev tap
dev tun0

;dev-node MyTap

ca /etc/openvpn/easy-rsa2/pki/ca.crt
cert /etc/openvpn/easy-rsa2/pki/issued/ovpn.crt
key /etc/openvpn/easy-rsa2/pki/private/ovpn.key # This file should be kept secret

# Diffie hellman parameters.
# Generate your own with:
# openssl dhparam -out dh2048.pem 2048
dh /etc/openvpn/easy-rsa2/pki/dh.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

ifconfig-pool-persist /var/log/openvpn/ipp.txt

;server-bridge 10.8.0.4 255.255.255.0 10.8.0.50 10.8.0.100

;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.x.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

push "redirect-gateway def1 bypass-dhcp"

push "dhcp-option DNS 192.168.x.40"
;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

;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-crypt /etc/openvpn/easy-rsa2/pki/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 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

;log /var/log/openvpn/openvpn.log
log-append /var/log/openvpn/openvpn.log

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
# Custom Changes
script-security 2
client-connect /etc/openvpn/connect.sh

#mode server
#tls-server
#key-direction 0

I Am trying to ping a VPN Client, ip 10.8.x.2, from a Computer located in the Subnet of my LAN 192.168.x.x .
The Ping from the VPN CLient to the LAN Client works perfectly, but not in that direction.
I Think my OpenVPN Server drops the package. I guess iptables allows all packages ( see previous Post ).
I'd like to mention, that I cannot ping the VPN Client from the VPN Server.

PS: The subnets are not overlapping