I tried to install openvpn on debian squeez (server) and connect from my fedora 17 as (client). Here is my configuration: server configuration ###cat server.conf # Serveur TCP ** proto tcp** port 1194 dev tun # Cles et certificats ca /etc/openvpn/easy-rsa/keys/ca.crt cert /etc/openvpn/easy-rsa/keys/server.crt key /etc/openvpn/easy-rsa/keys/server.key dh /etc/openvpn/easy-rsa/keys/dh1024.pem # Reseau #Adresse virtuel du reseau vpn server 192.170.70.0 255.255.255.0 #Cette ligne ajoute sur le client la route du reseau vers le serveur push "route 192.168.1.0 255.255.255.0" #Creer une route du server vers l'interface tun. #route 192.170.70.0 255.255.255.0 # Securite keepalive 10 120 #type d'encryptage des données **cipher AES-128-CBC** #activation de la compression comp-lzo #nombre maximum de clients autorisés max-clients 10 #pas d'utilisateur et groupe particuliers pour l'utilisation du VPN user nobody group nogroup #pour rendre la connexion persistante persist-key persist-tun #Log d'etat d'OpenVPN status /var/log/openvpn-status.log #logs openvpnlog /var/log/openvpn.log log-append /var/log/openvpn.log #niveau de verbosité verb 5 ###cat client.conf # Client client dev tun [COLOR="Red"]proto tcp-client[/COLOR] remote <my server wan IP> 1194 resolv-retry infinite **cipher AES-128-CBC** # Cles ca ca.crt cert client.crt key client.key # Securite nobind persist-key persist-tun comp-lzo verb 3 Message from the host client (fedora 17) in the log file / var / log / messages: Dec 6 21:56:00 GlobalTIC NetworkManager[691]: <info> Starting VPN service 'openvpn'... Dec 6 21:56:00 GlobalTIC NetworkManager[691]: <info> VPN service 'openvpn' started (org.freedesktop.NetworkManager.openvpn), PID 7470 Dec 6 21:56:00 GlobalTIC NetworkManager[691]: <info> VPN service 'openvpn' appeared; activating connections Dec 6 21:56:00 GlobalTIC NetworkManager[691]: <info> VPN plugin state changed: starting (3) Dec 6 21:56:01 GlobalTIC NetworkManager[691]: <info> VPN connection 'Connexion VPN 1' (Connect) reply received. Dec 6 21:56:01 GlobalTIC nm-openvpn[7472]: OpenVPN 2.2.2 x86_64-redhat-linux-gnu [SSL] [LZO2] [EPOLL] [PKCS11] [eurephia] built on Sep 5 2012 Dec 6 21:56:01 GlobalTIC nm-openvpn[7472]:[COLOR="Red"][U][B] WARNING: No server certificate verification method has been enabled.[/B][/U][/COLOR] See http://openvpn.net/howto.html#mitm for more info. Dec 6 21:56:01 GlobalTIC nm-openvpn[7472]: NOTE: the current --script-security setting may allow this configuration to call user-defined scripts Dec 6 21:56:01 GlobalTIC nm-openvpn[7472]:[COLOR="Red"] WARNING: file '/home/login/client/client.key' is group or others accessible[/COLOR] Dec 6 21:56:01 GlobalTIC nm-openvpn[7472]: UDPv4 link local: [undef] Dec 6 21:56:01 GlobalTIC nm-openvpn[7472]: UDPv4 link remote: [COLOR="Red"]<my server wan IP>[/COLOR]:1194 Dec 6 21:56:01 GlobalTIC nm-openvpn[7472]: [COLOR="Red"]read UDPv4 [ECONNREFUSED]: Connection refused (code=111)[/COLOR] Dec 6 21:56:03 GlobalTIC nm-openvpn[7472]: [COLOR="Red"]read UDPv4[/COLOR] [ECONNREFUSED]: Connection refused (code=111) Dec 6 21:56:07 GlobalTIC nm-openvpn[7472]: read UDPv4 [ECONNREFUSED]: Connection refused (code=111) Dec 6 21:56:15 GlobalTIC nm-openvpn[7472]: read UDPv4 [ECONNREFUSED]: Connection refused (code=111) Dec 6 21:56:31 GlobalTIC nm-openvpn[7472]: read UDPv4 [ECONNREFUSED]: Connection refused (code=111) Dec 6 21:56:41 GlobalTIC NetworkManager[691]: <warn> VPN connection 'Connexion VPN 1' (IP Conf[/CODE] ifconfig on server host(debian): ifconfig eth0 Link encap:Ethernet HWaddr 08:00:27:16:21:ac inet addr:192.168.1.6 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::a00:27ff:fe16:21ac/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:9059 errors:0 dropped:0 overruns:0 frame:0 TX packets:5660 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:919427 (897.8 KiB) TX bytes:1273891 (1.2 MiB) tun0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 inet addr:192.170.70.1 P-t-P:192.170.70.2 Mask:255.255.255.255 UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1 RX packets:0 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:0 (0.0 B) TX bytes:0 (0.0 B) ifconfig on the client host (fedora 17) as0t0: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST> mtu 1500 inet 5.5.0.1 netmask 255.255.252.0 destination 5.5.0.1 unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 txqueuelen 200 (UNSPEC) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 2 bytes 321 (321.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 as0t1: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST> mtu 1500 inet 5.5.4.1 netmask 255.255.252.0 destination 5.5.4.1 unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 txqueuelen 200 (UNSPEC) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 2 bytes 321 (321.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 as0t2: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST> mtu 1500 inet 5.5.8.1 netmask 255.255.252.0 destination 5.5.8.1 unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 txqueuelen 200 (UNSPEC) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 2 bytes 321 (321.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 as0t3: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST> mtu 1500 inet 5.5.12.1 netmask 255.255.252.0 destination 5.5.12.1 unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 txqueuelen 200 (UNSPEC) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 2 bytes 321 (321.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 **p255p1**: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.1.2 netmask 255.255.255.0 broadcast 192.168.1.255 inet6 fe80::21d:baff:fe20:b7e6 prefixlen 64 scopeid 0x20<link> ether 00:1d:ba:20:b7:e6 txqueuelen 1000 (Ethernet) RX packets 4842070 bytes 3579798184 (3.3 GiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 3996158 bytes 2436442882 (2.2 GiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 device interrupt 16 p255p1 is label for eth0 interface and on the server : root@hoteserver:/etc/openvpn# tree . +-- client ¦** +-- ca.crt ¦** +-- client.conf ¦** +-- client.crt ¦** +-- client.csr ¦** +-- client.key ¦** +-- client.ovpn ¦* ¦** +-- easy-rsa ¦** +-- build-ca ¦** +-- build-dh ¦** +-- build-inter ¦** +-- build-key ¦** +-- build-key-pass ¦** +-- build-key-pkcs12 ¦** +-- build-key-server ¦** +-- build-req ¦** +-- build-req-pass ¦** +-- clean-all ¦** +-- inherit-inter ¦** +-- keys ¦** ¦** +-- 01.pem ¦** ¦** +-- 02.pem ¦** ¦** +-- ca.crt ¦** ¦** +-- ca.key ¦** ¦** +-- client.crt ¦** ¦** +-- client.csr ¦** ¦** +-- client.key ¦** ¦** +-- dh1024.pem ¦** ¦** +-- index.txt ¦** ¦** +-- index.txt.attr ¦** ¦** +-- index.txt.attr.old ¦** ¦** +-- index.txt.old ¦** ¦** +-- serial ¦** ¦** +-- serial.old ¦** ¦** +-- server.crt ¦** ¦** +-- server.csr ¦** ¦** +-- server.key ¦** +-- list-crl ¦** +-- Makefile ¦** +-- openssl-0.9.6.cnf.gz ¦** +-- openssl.cnf ¦** +-- pkitool ¦** +-- README.gz ¦** +-- revoke-full ¦** +-- sign-req ¦** +-- vars ¦** +-- whichopensslcnf +-- openvpn.log +-- openvpn-status.log +-- server.conf +-- update-resolv-conf on the client: [login@hoteclient openvpn]$ tree . |-- easy-rsa | |-- 1.0 | | |-- build-ca | | |-- build-dh | | |-- build-inter | | |-- build-key | | |-- build-key-pass | | |-- build-key-pkcs12 | | |-- build-key-server | | |-- build-req | | |-- build-req-pass | | |-- clean-all | | |-- list-crl | | |-- make-crl | | |-- openssl.cnf | | |-- README | | |-- revoke-crt | | |-- revoke-full | | |-- sign-req | | `-- vars | `-- 2.0 | |-- build-ca | |-- build-dh | |-- build-inter | |-- build-key | |-- build-key-pass | |-- build-key-pkcs12 | |-- build-key-server | |-- build-req | |-- build-req-pass | |-- clean-all | |-- inherit-inter | |-- keys [error opening dir] | |-- list-crl | |-- Makefile | |-- openssl-0.9.6.cnf | |-- openssl-0.9.8.cnf | |-- openssl-1.0.0.cnf | |-- pkitool | |-- README | |-- revoke-full | |-- sign-req | |-- vars | `-- whichopensslcnf |-- keys -> ./easy-rsa/2.0/keys/ `-- server.conf the problem source is cipher AES-128-CBC ,proto tcp-client or UDP or the interface p255p1 on fedora17 or file authentification ta.key is not found ????