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Installation and Upgrades / OpenVPN connection reset issue

« on: June 28, 2010, 02:07:08 pm »

Hi to all. I'm new to this forum though not new to linux world.

I'm having a hard time configuring an OpenVPN server on eBox machine.
I followed the eBox-for-Network-Administrators.pdf documentation to set up a server and Windows client. However, trying to establish a connection gave me the following error:

Code: [Select]

Mon Jun 28 09:43:34 2010 OpenVPN 2.1_rc20 i686-pc-mingw32 [SSL] [LZO2] [PKCS11] built on Oct  1 2009
Mon Jun 28 09:43:34 2010 WARNING: Make sure you understand the semantics of --tls-remote before using it (see the man page).
Mon Jun 28 09:43:34 2010 NOTE: OpenVPN 2.1 requires '--script-security 2' or higher to call user-defined scripts or executables
Mon Jun 28 09:43:34 2010 LZO compression initialized
Mon Jun 28 09:43:34 2010 Control Channel MTU parms [ L:1574 D:138 EF:38 EB:0 ET:0 EL:0 ]
Mon Jun 28 09:43:34 2010 Data Channel MTU parms [ L:1574 D:1450 EF:42 EB:135 ET:32 EL:0 AF:3/1 ]
Mon Jun 28 09:43:34 2010 Local Options hash (VER=V4): 'd79ca330'
Mon Jun 28 09:43:34 2010 Expected Remote Options hash (VER=V4): 'f7df56b8'
Mon Jun 28 09:43:34 2010 Socket Buffers: R=[8192->8192] S=[8192->8192]
Mon Jun 28 09:43:34 2010 UDPv4 link local: [undef]
Mon Jun 28 09:43:34 2010 UDPv4 link remote: 192.168.1.21:1194
Mon Jun 28 09:43:34 2010 TLS: Initial packet from 192.168.1.21:1194, sid=c2a50381 6a9cbb9a
Mon Jun 28 09:43:34 2010 VERIFY OK: depth=1, /C=SI/L=Medvode/O=ARDEVI_d.o.o./CN=Certification_Authority_Certificate
Mon Jun 28 09:43:34 2010 VERIFY X509NAME OK: /C=SI/L=Medvode/O=ARDEVI_d.o.o./CN=office2
Mon Jun 28 09:43:34 2010 VERIFY OK: depth=0, /C=SI/L=Medvode/O=ARDEVI_d.o.o./CN=office2
Mon Jun 28 09:44:35 2010 TLS Error: TLS key negotiation failed to occur within 60 seconds (check your network connectivity)
Mon Jun 28 09:44:35 2010 TLS Error: TLS handshake failed
Mon Jun 28 09:44:35 2010 TCP/UDP: Closing socket
Troubleshooting the above, I have disabled the firewall completely on Windows client as well as allowed any connection to eBox server.
It would appear as if something is still blocking UDP connection as changing to TCP protocol I was able to move a step further to the following:

Code: [Select]

Mon Jun 28 11:07:36 2010 OpenVPN 2.1_rc20 i686-pc-mingw32 [SSL] [LZO2] [PKCS11] built on Oct  1 2009
Mon Jun 28 11:07:36 2010 WARNING: Make sure you understand the semantics of --tls-remote before using it (see the man page).
Mon Jun 28 11:07:36 2010 NOTE: OpenVPN 2.1 requires '--script-security 2' or higher to call user-defined scripts or executables
Mon Jun 28 11:07:36 2010 LZO compression initialized
Mon Jun 28 11:07:36 2010 Control Channel MTU parms [ L:1576 D:140 EF:40 EB:0 ET:0 EL:0 ]
Mon Jun 28 11:07:36 2010 Data Channel MTU parms [ L:1576 D:1450 EF:44 EB:135 ET:32 EL:0 AF:3/1 ]
Mon Jun 28 11:07:36 2010 Local Options hash (VER=V4): '31fdf004'
Mon Jun 28 11:07:36 2010 Expected Remote Options hash (VER=V4): '3e6d1056'
Mon Jun 28 11:07:36 2010 Attempting to establish TCP connection with 192.168.1.21:1194
Mon Jun 28 11:07:36 2010 TCP connection established with 192.168.1.21:1194
Mon Jun 28 11:07:36 2010 Socket Buffers: R=[8192->8192] S=[8192->8192]
Mon Jun 28 11:07:36 2010 TCPv4_CLIENT link local: [undef]
Mon Jun 28 11:07:36 2010 TCPv4_CLIENT link remote: 192.168.1.21:1194
Mon Jun 28 11:07:36 2010 TLS: Initial packet from 192.168.1.21:1194, sid=8161fef3 d5d22836
Mon Jun 28 11:07:37 2010 VERIFY OK: depth=1, /C=SI/L=Medvode/O=ARDEVI_d.o.o./CN=Certification_Authority_Certificate
Mon Jun 28 11:07:37 2010 VERIFY X509NAME OK: /C=SI/L=Medvode/O=ARDEVI_d.o.o./CN=office2
Mon Jun 28 11:07:37 2010 VERIFY OK: depth=0, /C=SI/L=Medvode/O=ARDEVI_d.o.o./CN=office2
Mon Jun 28 11:07:37 2010 Connection reset, restarting [-1]
Mon Jun 28 11:07:37 2010 TCP/UDP: Closing socket
Mon Jun 28 11:07:37 2010 SIGUSR1[soft,connection-reset] received, process restarting
Mon Jun 28 11:07:37 2010 Restart pause, 5 second(s)
Mon Jun 28 11:07:42 2010 WARNING: Make sure you understand the semantics of --tls-remote before using it (see the man page).
Mon Jun 28 11:07:42 2010 NOTE: OpenVPN 2.1 requires '--script-security 2' or higher to call user-defined scripts or executables
Mon Jun 28 11:07:42 2010 Re-using SSL/TLS context
Mon Jun 28 11:07:42 2010 LZO compression initialized
Mon Jun 28 11:07:42 2010 Control Channel MTU parms [ L:1576 D:140 EF:40 EB:0 ET:0 EL:0 ]
Mon Jun 28 11:07:42 2010 Data Channel MTU parms [ L:1576 D:1450 EF:44 EB:135 ET:32 EL:0 AF:3/1 ]
Mon Jun 28 11:07:42 2010 Local Options hash (VER=V4): '31fdf004'
Mon Jun 28 11:07:42 2010 Expected Remote Options hash (VER=V4): '3e6d1056'
Mon Jun 28 11:07:42 2010 Attempting to establish TCP connection with 192.168.1.21:1194
Mon Jun 28 11:07:42 2010 TCP connection established with 192.168.1.21:1194
Mon Jun 28 11:07:42 2010 Socket Buffers: R=[8192->8192] S=[8192->8192]
Mon Jun 28 11:07:42 2010 TCPv4_CLIENT link local: [undef]
Mon Jun 28 11:07:42 2010 TCPv4_CLIENT link remote: 192.168.1.21:1194
Mon Jun 28 11:07:42 2010 TLS: Initial packet from 192.168.1.21:1194, sid=dc1563a1 c70b0f77
Mon Jun 28 11:07:42 2010 VERIFY OK: depth=1, /C=SI/L=Medvode/O=ARDEVI_d.o.o./CN=Certification_Authority_Certificate
Mon Jun 28 11:07:42 2010 VERIFY X509NAME OK: /C=SI/L=Medvode/O=ARDEVI_d.o.o./CN=office2
Mon Jun 28 11:07:42 2010 VERIFY OK: depth=0, /C=SI/L=Medvode/O=ARDEVI_d.o.o./CN=office2
Mon Jun 28 11:07:42 2010 write TCPv4_CLIENT: Software caused connection abort (WSAECONNABORTED) (code=10053)
Mon Jun 28 11:07:42 2010 Connection reset, restarting [-1]
Allowed the client running (reestablishing the connection) the aforementioned output would go to indefinite.


Server configuration:

Code: [Select]

eBox 1.4.4 (2.6.24-27-ebox) virtualized on VMware Server 2.0.2
Module status:
Network, Firewall, Events, Logs, Monitor, VPN, Users and Groups
Network:
Single NIC configuration, behind NAT
OpenVPN configuration (OpenVPN 2.1_rc7)

Code: [Select]

# EBox OpenVPN 2.0 config file for  server office2


# Which local IP address should OpenVPN
# listen on? (optional)




# Which TCP/UDP port should OpenVPN listen on?

port 1194


# TCP or UDP server?

proto tcp


# virtual device

dev tap0


# SSL/TLS root certificate (ca), certificate

# (cert), and private key (key).

ca '/var/lib/ebox/CA/cacert.pem'


cert '/var/lib/ebox/CA/certs/5A02887753DEBEF5.pem'


key '/var/lib/ebox/CA/private/office2.pem'
 # This file should be kept secret

# check peer certificate against certificate revokation list

crl-verify /var/lib/ebox/CA/crl/latest.pem
 

# 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 /etc/openvpn/dh1024.pem

dh /etc/openvpn/ebox-dh1024.pem


# Configure server mode and supply a VPN subnet
# for OpenVPN to draw client addresses from.
server 192.168.160.0 255.255.255.0

# Maintain a record of client <-> virtual IP address
# associations in this file. 
ifconfig-pool-persist ipp.txt


# If enabled, this directive will configure
# all clients to redirect their default
# network gateway through the VPN
;push "redirect-gateway"


# Uncomment this directive to allow different
# clients to be able to "see" each other.

client-to-client


# The keepalive directive causes ping-like
# messages to be sent back and forth over
keepalive 10 120


# client certificate common name authentication



# For extra security beyond that provided
# by SSL/TLS, create an "HMAC firewall"
# to help block DoS attacks and UDP port flooding.
;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 100

# group and user for the OpenVPN
# daemon's privileges after initialization.

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/ebox/openvpn/status-office2.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-append  /var/log/ebox/openvpn/office2.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

   push "route 192.168.1.0 255.255.255.0"
Client configuration (OpenVPN-2.1_rc20)

Code: [Select]

##############################################
# 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

# 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.

# Are we connecting to a TCP or
# UDP server?  Use the same setting as
# on the server.
proto tcp

# The hostname/IP and port of the server.
# You can have multiple remote entries
# to load balance between the servers.
remote  office2.ardevi.si 1194
remote  192.168.1.21 1194
remote  217.72.87.230 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




# 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   cacert.pem
cert 5A02887753DEBEF4.pem
key  jure.pem

# Verify server certificate by common name
   tls-remote office2


# Verify server certificate by checking
# that the certicate has the nsCertType
# field set to "server".  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 nsCertType
# field set to "server".  The build-key-server
# script in the easy-rsa folder will do this.
;ns-cert-type 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.
;cipher x

# 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
All tests were carried out from internal network to rule out any NAT issue.

I gather the SIGUSR1 process restarting message generally indicates the OpenVPN process (either client or server) can't communicate with the
remote machine over OpenVPN's TCP or UDP port, but I'm clueless as to what could be the issue.

TIA

Gasper