OpenVPN failures on Server but not Client

a2jagger · Post by **a2jagger** » Mon Aug 08, 2011 2:12 pm

Hi, I would appreciate any help folks with more experience on OpenVPN and Fedora 14 may have. I have installed OpenVPN on two virtual machines running on my Mac. Both are Fedora 14 installs. I have a Netgear N300 Router. All of the proper certificates and keys have been built and the config files initialize (however on the server if I stop openvpn and later run the command "openvpn server.conf" I always get kicked out with the error "port 1194 already in use" - the only fix I have found is to reboot). So even on initial initialization on server and client where tunnels are created and data looks like it is moving, I always get a fail on the server side. I have included as much from the system logs as I could below rather than try to explain all of it. I have shut down the firewalls and enabled port forwarding on my router. Any help getting OpenVPN working on my system would be greatly appreciated. Thanks.

This is the data from the server after reboot (states that a peer to peer connection was made and the ifconfig shows data moving through tun0, however the chkconfig shows the program off and when I try to start it I get a fail):

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[root@Ismaros openvpn]# openvpn server.conf
Sun Aug  7 23:07:36 2011 us=254451 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.
Sun Aug  7 23:07:36 2011 us=254467 NOTE: OpenVPN 2.1 requires '--script-security 2' or higher to call user-defined scripts or executables
Sun Aug  7 23:07:36 2011 us=257720 Diffie-Hellman initialized with 1024 bit key
Sun Aug  7 23:07:36 2011 us=259170 TLS-Auth MTU parms [ L:1542 D:138 EF:38 EB:0 ET:0 EL:0 ]
Sun Aug  7 23:07:36 2011 us=262959 ROUTE default_gateway=192.168.1.1
Sun Aug  7 23:07:36 2011 us=316011 TUN/TAP device tun0 opened
Sun Aug  7 23:07:36 2011 us=316455 TUN/TAP TX queue length set to 100
Sun Aug  7 23:07:36 2011 us=316493 /sbin/ip link set dev tun0 up mtu 1500
Sun Aug  7 23:07:36 2011 us=333864 /sbin/ip addr add dev tun0 local 10.8.0.1 peer 10.8.0.2
Sun Aug  7 23:07:36 2011 us=335407 /sbin/ip route add 10.8.0.0/24 via 10.8.0.2
Sun Aug  7 23:07:36 2011 us=341516 Data Channel MTU parms [ L:1542 D:1450 EF:42 EB:135 ET:0 EL:0 AF:3/1 ]
Sun Aug  7 23:07:36 2011 us=341552 Socket Buffers: R=[126976->131072] S=[126976->131072]
Sun Aug  7 23:07:36 2011 us=341566 UDPv4 link local (bound): [undef]:1194
Sun Aug  7 23:07:36 2011 us=341574 UDPv4 link remote: [undef]
Sun Aug  7 23:07:36 2011 us=341590 MULTI: multi_init called, r=256 v=256
Sun Aug  7 23:07:36 2011 us=341626 IFCONFIG POOL: base=10.8.0.4 size=62
Sun Aug  7 23:07:36 2011 us=341652 Initialization Sequence Completed
Sun Aug  7 23:07:37 2011 us=451095 MULTI: multi_create_instance called
Sun Aug  7 23:07:37 2011 us=451141 192.168.1.2:56429 Re-using SSL/TLS context
Sun Aug  7 23:07:37 2011 us=451167 192.168.1.2:56429 LZO compression initialized
Sun Aug  7 23:07:37 2011 us=451245 192.168.1.2:56429 Control Channel MTU parms [ L:1542 D:138 EF:38 EB:0 ET:0 EL:0 ]
Sun Aug  7 23:07:37 2011 us=451259 192.168.1.2:56429 Data Channel MTU parms [ L:1542 D:1450 EF:42 EB:135 ET:0 EL:0 AF:3/1 ]
Sun Aug  7 23:07:37 2011 us=451289 192.168.1.2:56429 Local Options String: 'V4,dev-type tun,link-mtu 1542,tun-mtu 1500,proto UDPv4,comp-lzo,cipher BF-CBC,auth SHA1,keysize 128,key-method 2,tls-server'
Sun Aug  7 23:07:37 2011 us=451302 192.168.1.2:56429 Expected Remote Options String: 'V4,dev-type tun,link-mtu 1542,tun-mtu 1500,proto UDPv4,comp-lzo,cipher BF-CBC,auth SHA1,keysize 128,key-method 2,tls-client'
Sun Aug  7 23:07:37 2011 us=451321 192.168.1.2:56429 Local Options hash (VER=V4): '530fdded'
Sun Aug  7 23:07:37 2011 us=451333 192.168.1.2:56429 Expected Remote Options hash (VER=V4): '41690919'
Sun Aug  7 23:07:37 2011 us=451368 192.168.1.2:56429 TLS: Initial packet from 192.168.1.2:56429, sid=5bd4c596 74eca0e8
Sun Aug  7 23:07:37 2011 us=471482 192.168.1.2:56429 VERIFY OK: depth=1, /C=US/ST=SC/L=MountPleasant/O=Uly-Group/CN=cimsdeu.org/emailAddress=alewis@theuly.com
Sun Aug  7 23:07:37 2011 us=471581 192.168.1.2:56429 VERIFY OK: depth=0, /C=US/ST=SC/L=MountPleasant/O=Uly-Group/OU=DEUClient/CN=testclient1/emailAddress=alewis@theuly.com
Sun Aug  7 23:07:37 2011 us=479346 192.168.1.2:56429 Data Channel Encrypt: Cipher 'BF-CBC' initialized with 128 bit key
Sun Aug  7 23:07:37 2011 us=479375 192.168.1.2:56429 Data Channel Encrypt: Using 160 bit message hash 'SHA1' for HMAC authentication
Sun Aug  7 23:07:37 2011 us=479421 192.168.1.2:56429 Data Channel Decrypt: Cipher 'BF-CBC' initialized with 128 bit key
Sun Aug  7 23:07:37 2011 us=479431 192.168.1.2:56429 Data Channel Decrypt: Using 160 bit message hash 'SHA1' for HMAC authentication
Sun Aug  7 23:07:37 2011 us=480456 192.168.1.2:56429 Control Channel: TLSv1, cipher TLSv1/SSLv3 DHE-RSA-AES256-SHA, 1024 bit RSA
Sun Aug  7 23:07:37 2011 us=480484 192.168.1.2:56429 [testclient1] Peer Connection Initiated with 192.168.1.2:56429
Sun Aug  7 23:07:37 2011 us=480526 testclient1/192.168.1.2:56429 MULTI: Learn: 10.8.0.6 -> testclient1/192.168.1.2:56429
Sun Aug  7 23:07:37 2011 us=480537 testclient1/192.168.1.2:56429 MULTI: primary virtual IP for testclient1/192.168.1.2:56429: 10.8.0.6
Sun Aug  7 23:07:38 2011 us=167649 MULTI: multi_create_instance called
Sun Aug  7 23:07:40 2011 us=517982 testclient1/76.23.126.76:54098 PUSH: Received control message: 'PUSH_REQUEST'
Sun Aug  7 23:07:40 2011 us=518052 testclient1/76.23.126.76:54098 SENT CONTROL [testclient1]: 'PUSH_REPLY,route 10.8.0.1,topology net30,ping 10,ping-restart 120,ifconfig 10.8.0.6 10.8.0.5' (status=1)

Configuration and routing table from server:

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[root@Ismaros ~]# ifconfig
eth2      Link encap:Ethernet  HWaddr 00:0C:29:3A:87:F5  
          inet addr:192.168.1.3  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::20c:29ff:fe3a:87f5/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:6614 errors:5106 dropped:0 overruns:0 frame:0
          TX packets:4623 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1145158 (1.0 MiB)  TX bytes:1416509 (1.3 MiB)
          Interrupt:19 Base address:0x2024 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:66 errors:0 dropped:0 overruns:0 frame:0
          TX packets:66 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:180394 (176.1 KiB)  TX bytes:180394 (176.1 KiB)

tun0      Link encap:UNSPEC  HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  
          inet addr:10.8.0.1  P-t-P:10.8.0.2  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
          RX packets:584 errors:0 dropped:0 overruns:0 frame:0
          TX packets:16913881 errors:0 dropped:16896619 overruns:0 carrier:0
          collisions:0 txqueuelen:100 
          RX bytes:49240 (48.0 KiB)  TX bytes:25358625224 (23.6 GiB)

[root@Ismaros ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.8.0.2        0.0.0.0         255.255.255.255 UH    0      0        0 tun0
10.8.0.0        10.8.0.2        255.255.255.0   UG    0      0        0 tun0
192.168.1.0     0.0.0.0         255.255.255.0   U     1      0        0 eth2
0.0.0.0         192.168.1.1     0.0.0.0         UG    0      0        0 eth2

When I checke service levels and tried to start OpenVPN I got the following:

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[root@Ismaros ~]# chkconfig --list | grep -E "openvpn|bridge"
openvpn        	0:off	1:off	2:off	3:off	4:off	5:off	6:off
[root@Ismaros ~]# service openvpn start
Starting openvpn:                                          [FAILED]
[root@Ismaros ~]#

Here is the data after the reboot (on the client machine tun3 was opened vice tun0 on the server machine - not sure if this is a problem or not):

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[root@lewis openvpn]# openvpn --config client.conf
Thu Aug  4 20:49:08 2011 us=907268 OpenVPN 2.1.1 i686-redhat-linux-gnu [SSL] [LZO2] [EPOLL] [PKCS11] built on Jan  5 2010
Thu Aug  4 20:49:08 2011 us=907337 NOTE: OpenVPN 2.1 requires '--script-security 2' or higher to call user-defined scripts or executables
Thu Aug  4 20:49:08 2011 us=908006 WARNING: file '/etc/openvpn/keys/testclient1.key' is group or others accessible
Thu Aug  4 20:49:08 2011 us=908503 LZO compression initialized
Thu Aug  4 20:49:08 2011 us=908562 Control Channel MTU parms [ L:1542 D:138 EF:38 EB:0 ET:0 EL:0 ]
Thu Aug  4 20:49:08 2011 us=977568 Data Channel MTU parms [ L:1542 D:1450 EF:42 EB:135 ET:0 EL:0 AF:3/1 ]
Thu Aug  4 20:49:08 2011 us=977613 Local Options String: 'V4,dev-type tun,link-mtu 1542,tun-mtu 1500,proto UDPv4,comp-lzo,cipher BF-CBC,auth SHA1,keysize 128,key-method 2,tls-client'
Thu Aug  4 20:49:08 2011 us=977623 Expected Remote Options String: 'V4,dev-type tun,link-mtu 1542,tun-mtu 1500,proto UDPv4,comp-lzo,cipher BF-CBC,auth SHA1,keysize 128,key-method 2,tls-server'
Thu Aug  4 20:49:08 2011 us=977644 Local Options hash (VER=V4): '41690919'
Thu Aug  4 20:49:08 2011 us=977658 Expected Remote Options hash (VER=V4): '530fdded'
Thu Aug  4 20:49:08 2011 us=977677 Socket Buffers: R=[114688->131072] S=[114688->131072]
Thu Aug  4 20:49:08 2011 us=977691 UDPv4 link local: [undef]
Thu Aug  4 20:49:08 2011 us=977701 UDPv4 link remote: 76.23.126.76:1194
Thu Aug  4 20:49:08 2011 us=979754 TLS: Initial packet from 76.23.126.76:1194, sid=75ac7945 0f64820c
Thu Aug  4 20:49:08 2011 us=993988 VERIFY OK: depth=1, /C=US/ST=SC/L=MountPleasant/O=Uly-Group/CN=cimsdeu.org/emailAddress=alewis@theuly.com
Thu Aug  4 20:49:08 2011 us=994178 VERIFY OK: nsCertType=SERVER
Thu Aug  4 20:49:08 2011 us=994191 VERIFY OK: depth=0, /C=US/ST=SC/L=MountPleasant/O=Uly-Group/CN=cimsdeu.org/emailAddress=alewis@theuly.com
Thu Aug  4 20:49:09 2011 us=67874 Data Channel Encrypt: Cipher 'BF-CBC' initialized with 128 bit key
Thu Aug  4 20:49:09 2011 us=67908 Data Channel Encrypt: Using 160 bit message hash 'SHA1' for HMAC authentication
Thu Aug  4 20:49:09 2011 us=67958 Data Channel Decrypt: Cipher 'BF-CBC' initialized with 128 bit key
Thu Aug  4 20:49:09 2011 us=67969 Data Channel Decrypt: Using 160 bit message hash 'SHA1' for HMAC authentication
Thu Aug  4 20:49:09 2011 us=68006 Control Channel: TLSv1, cipher TLSv1/SSLv3 DHE-RSA-AES256-SHA, 1024 bit RSA
Thu Aug  4 20:49:09 2011 us=68030 [cimsdeu.org] Peer Connection Initiated with 76.23.126.76:1194
Thu Aug  4 20:49:11 2011 us=765840 SENT CONTROL [cimsdeu.org]: 'PUSH_REQUEST' (status=1)
Thu Aug  4 20:49:11 2011 us=767060 PUSH: Received control message: 'PUSH_REPLY,route 10.8.0.1,topology net30,ping 10,ping-restart 120,ifconfig 10.8.0.6 10.8.0.5'
Thu Aug  4 20:49:11 2011 us=767108 OPTIONS IMPORT: timers and/or timeouts modified
Thu Aug  4 20:49:11 2011 us=767118 OPTIONS IMPORT: --ifconfig/up options modified
Thu Aug  4 20:49:11 2011 us=767126 OPTIONS IMPORT: route options modified
Thu Aug  4 20:49:11 2011 us=767449 ROUTE default_gateway=192.168.30.2
Thu Aug  4 20:49:11 2011 us=769313 TUN/TAP device tun3 opened
Thu Aug  4 20:49:11 2011 us=769340 TUN/TAP TX queue length set to 100
Thu Aug  4 20:49:11 2011 us=769365 /sbin/ip link set dev tun3 up mtu 1500
Thu Aug  4 20:49:11 2011 us=774448 /sbin/ip addr add dev tun3 local 10.8.0.6 peer 10.8.0.5
Thu Aug  4 20:49:11 2011 us=779683 /sbin/ip route add 10.8.0.1/32 via 10.8.0.5
RTNETLINK answers: File exists
Thu Aug  4 20:49:11 2011 us=780388 ERROR: Linux route add command failed: external program exited with error status: 2
Thu Aug  4 20:49:11 2011 us=780410 Initialization Sequence Completed

Here is the configuration and routing table for the client machine:

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[root@lewis ~]# ifconfig
eth0      Link encap:Ethernet  HWaddr 00:0C:29:F6:72:26  
          inet addr:192.168.30.134  Bcast:192.168.30.255  Mask:255.255.255.0
          inet6 addr: fe80::20c:29ff:fef6:7226/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:99624 errors:0 dropped:0 overruns:0 frame:0
          TX packets:171629 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:58144318 (55.4 MiB)  TX bytes:18669378 (17.8 MiB)
          Interrupt:19 Base address:0x2000 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:26 errors:0 dropped:0 overruns:0 frame:0
          TX packets:26 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:1540 (1.5 KiB)  TX bytes:1540 (1.5 KiB)

tun0      Link encap:UNSPEC  HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  
          inet addr:10.8.0.6  P-t-P:10.8.0.5  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
          RX packets:10316 errors:0 dropped:0 overruns:0 frame:0
          TX packets:40552 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100 
          RX bytes:1789608 (1.7 MiB)  TX bytes:4276470 (4.0 MiB)

tun1      Link encap:UNSPEC  HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  
          inet addr:10.8.0.6  P-t-P:10.8.0.5  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
          RX packets:9440 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100 
          RX bytes:14160000 (13.5 MiB)  TX bytes:0 (0.0 b)

tun2      Link encap:UNSPEC  HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  
          inet addr:10.8.0.6  P-t-P:10.8.0.5  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
          RX packets:2129 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100 
          RX bytes:3193500 (3.0 MiB)  TX bytes:0 (0.0 b)

tun3      Link encap:UNSPEC  HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  
          inet addr:10.8.0.6  P-t-P:10.8.0.5  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
          RX packets:500 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100 
          RX bytes:750000 (732.4 KiB)  TX bytes:0 (0.0 b)

[root@lewis ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun0
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun1
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun2
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun3
10.8.0.1        10.8.0.5        255.255.255.255 UGH   0      0        0 tun0
192.168.30.0    0.0.0.0         255.255.255.0   U     1      0        0 eth0
0.0.0.0         192.168.30.2    0.0.0.0         UG    0      0        0 eth0

Post by **Mimiko** » Mon Aug 08, 2011 2:28 pm

Why do you need so much tun interfaces?
Show client's config file. I see some external file is called on tun up.

Post by **janjust** » Mon Aug 08, 2011 3:25 pm

if you first run

openvpn server.conf

and then

chkconfig openvpn on

then you're going to see failures , as openvpn is already running. Try

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chkconfig openvpn on

and reboot and openvpn should be automatically up.

As for mimiko's question: where did tun0-3 come from? each client connection will open only a single tun interface and having 3 tun interfaces , all with the same IP config , are bound to give you problems - is your client OS installation in order?

a2jagger · Post by **a2jagger** » Mon Aug 08, 2011 3:38 pm

I am not sure about the tun interfaces I just am not that experienced, I assume they open when I try to start OpenVPN. He are the confi files. I did not take out any of the notes from the original sample so you could see exactly what they look like.

Server config:

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 #################################################
# 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 192.168.1.3

# 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 /etc/openvpn/easy-rsa/2.0/keys/ca.crt
cert /etc/openvpn/easy-rsa/2.0/keys/cimsdeu.org.crt
key /etc/openvpn/easy-rsa/2.0/keys/cimsdeu.org.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 /etc/openvpn/easy-rsa/2.0/keys/dh1024.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 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 --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 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 nobody

# 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 4

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

Client config:

Code: Select all

 
##############################################
# 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 cimsdeu.org 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 nobody
;group nobody

# 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 /etc/openvpn/keys/ca.crt
cert /etc/openvpn/keys/testclient1.crt
key /etc/openvpn/keys/testclient1.key

# 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 4

# Silence repeating messages
;mute 20

Post by **Mimiko** » Mon Aug 08, 2011 3:57 pm

Try what janjust write.

On the server when you stop OpenVPN, using "ps x" shows you that OpenVPN is still running?

janjust. Those tun's happens to be at client - that strange for me.

a2jagger · Post by **a2jagger** » Mon Aug 08, 2011 4:11 pm

Thanks. Here is what I got so far. When I try to stop OpenVPN on the server, it never seems to quit and every time I try to start it afterwards it fails and tells me port 1194 is in use. I use "ps -aux" to find the PID code to kill it, but even that hasn't worked so rebooting is the only thing I have found that gets me back to a place where I can initialize the program (but still not actually connect to the client).

I tried the "chkconfig openvpn on" that janjust suggested and I did not get any further information. The only thing that happened was that it returned a new command prompt line once I hit enter. I rebooted and tried it again and got the same. Did I miss something? Thanks.

Code: Select all

[root@Ismaros ~]# chkconfig openvpn on
[root@Ismaros ~]#

a2jagger · Post by **a2jagger** » Mon Aug 08, 2011 9:28 pm

Hi guys. I tried a few more times and finally got a little different result, but I still get a fail on the server when I try to start OpenVPN. The one change I noticed after running the command janjust recommended was that I was able to get OpenVPN to come on on levels2-5 after a few steps on the server. I have posted everything below starting with the client machine. Oh and it appears as if a new tun interface opens on the client side every time I use the "service openvpn start" command, they just don't close when the command to stop is given.

Client machine data:

Code: Select all

 
[root@lewis ~]# service openvpn start
Starting openvpn:                                          [  OK  ]
[root@lewis ~]# chkconfig --list | grep -E "openvpn|bridge"
openvpn        	0:off	1:off	2:off	3:off	4:off	5:off	6:off
[root@lewis ~]# service openvpn stop
Shutting down openvpn:                                     [  OK  ]
[root@lewis ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun0
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun1
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun2
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun3
10.8.0.1        10.8.0.5        255.255.255.255 UGH   0      0        0 tun0
192.168.30.0    0.0.0.0         255.255.255.0   U     1      0        0 eth0
0.0.0.0         192.168.30.2    0.0.0.0         UG    0      0        0 eth0
[root@lewis ~]# chkconfig openvpn on
[root@lewis ~]# chkconfig --list | grep -E "openvpn|bridge"
openvpn        	0:off	1:off	2:on	3:on	4:on	5:on	6:off
[root@lewis ~]# service openvpn start
Starting openvpn:                                          [  OK  ]
[root@lewis ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun0
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun1
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun2
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun3
10.8.0.5        0.0.0.0         255.255.255.255 UH    0      0        0 tun4
10.8.0.1        10.8.0.5        255.255.255.255 UGH   0      0        0 tun0
192.168.30.0    0.0.0.0         255.255.255.0   U     1      0        0 eth0
0.0.0.0         192.168.30.2    0.0.0.0         UG    0      0        0 eth0

Here is the server data (still getting fails - I am guessing from the same problem that I had all weekend "Socket bind failed on local address [undef]:1194: Address already in use"):

Code: Select all

  
[root@Ismaros ~]# chkconfig openvpn on
[root@Ismaros ~]# chkconfig --list | grep -E "openvpn|bridge"
openvpn        	0:off	1:off	2:on	3:on	4:on	5:on	6:off
[root@Ismaros ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.8.0.2        0.0.0.0         255.255.255.255 UH    0      0        0 tun0
192.168.1.0     0.0.0.0         255.255.255.0   U     1      0        0 eth2
10.8.0.0        10.8.0.2        255.255.255.0   UG    0      0        0 tun0
0.0.0.0         192.168.1.1     0.0.0.0         UG    0      0        0 eth2
[root@Ismaros ~]# service openvpn start
Starting openvpn:                                          [FAILED]
[root@Ismaros ~]# cd /etc/openvpn
[root@Ismaros openvpn]# openvpn server.conf
Mon Aug  8 17:09:21 2011 us=455612 OpenVPN 2.1.1 x86_64-redhat-linux-gnu [SSL] [LZO2] [EPOLL] [PKCS11] built on Jan  5 2010
Mon Aug  8 17:09:21 2011 us=459673 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.
Mon Aug  8 17:09:21 2011 us=459693 NOTE: OpenVPN 2.1 requires '--script-security 2' or higher to call user-defined scripts or executables
Mon Aug  8 17:09:21 2011 us=462010 Diffie-Hellman initialized with 1024 bit key
Mon Aug  8 17:09:21 2011 us=462619 TLS-Auth MTU parms [ L:1542 D:138 EF:38 EB:0 ET:0 EL:0 ]
Mon Aug  8 17:09:21 2011 us=466057 TCP/UDP: Socket bind failed on local address [undef]:1194: Address already in use
Mon Aug  8 17:09:21 2011 us=466077 Exiting
[root@Ismaros openvpn]#

One other question - what is it supposed to look like once everything works? Will I be able to use a browser to go to my server and view the pages I have hosted there or will everything remain in the command line? I want to be able to have remote individuals access a database through a GUI that is set up like a web page. I had assumed once the connection was established I would pull up a browser, type in the server url and then get a HTTPS in the address.

Post by **Mimiko** » Tue Aug 09, 2011 6:30 am

Delete on client tun1-tun4.

[root@Ismaros ~]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.8.0.2 0.0.0.0 255.255.255.255 UH 0 0 0 tun0
192.168.1.0 0.0.0.0 255.255.255.0 U 1 0 0 eth2
10.8.0.0 10.8.0.2 255.255.255.0 UG 0 0 0 tun0
0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth2
[root@Ismaros ~]# service openvpn start
Starting openvpn: [FAILED]

Route command shows active OpenVPN, than you want to start it again. It will not work.

Could you update your OpenVPN? 2.1.1 is kind old.

Will I be able to use a browser to go to my server and view the pages I have hosted there or will everything remain in the command line? I want to be able to have remote individuals access a database through a GUI that is set up like a web page. I had assumed once the connection was established I would pull up a browser, type in the server url and then get a HTTPS in the address.

yes, using 10.8.0.1. If you use DNS name, you will get public IP address, which will go thru your local gateway, not thru tunnel.

what is it supposed to look like once everything works?

You have to see in log: Initialization complete.

Post by **maikcat** » Tue Aug 09, 2011 7:06 am

hi there,

chkconfig command does NOT start or stop any services,
it simply configures in which runlevel which services start and by which order (dependencies, you cant have sshd running without network..)
it does that by creating links (starting with S and K) into appropriate directories (rc0.d to rc6.d)

so when you execute chkconfig openvpn on
it configures openvpn to run the NEXT time you reboot nothing more nothing less,
if you use centos/redhat/fedora distro try using ntsysv utility..

Michael.

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OpenVPN failures on Server but not Client

OpenVPN failures on Server but not Client

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Re: OpenVPN failures on Server but not Client

Re: OpenVPN failures on Server but not Client

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Re: OpenVPN failures on Server but not Client