Airvpn - ArchWiki

# Airvpn

## Configuring OpenVPN to connect as a client to an AirVPN server

OpenVPN describes configuration from scratch for both servers and clients, including generating keys and certificates.

If you're interested in simply getting openvpn to work with credentials provided by a third-party VPN service, just install the openvpn package available in the official repositories.

Airvpn generates your config for you, if you have an account and are logged in. You can choose a server, port, and proxy settings, and download a zip file with certificates and settings. I downloaded it from "Access without a client" on 01.20.2012.

You should now have an archive air.zip containing 4 files:

     air.ovpn ca.crt  user.crt  user.key

Extract them to /etc/openvpn:

     # bsdtar -C /etc/openvpn -xf ~/air.zip

Note that user.key is your secret key. Don't share it or let it be compromised!

Open air.ovpn and note the lines

    ca "ca.crt"
    user "user.crt"
    key  "user.key"

These assume that these three files are in the same directory as air.ovpn. If you move them elsewhere, set their new absolute paths in air.ovpn; else it won't be able to find them.

Set permissions on the files and delete the zip:

     # chmod 400 air.ovpn ca.crt  user.crt  user.key
     # shred --remove ~/air.zip

Point openvpn at the config file as superuser:

    # openvpn --config /etc/openvpn/air.ovpn

You should get a couple dozen verbose connection logs, hopefully ending in something like

    Sat Jan 21 02:16:47 2012 Initialization Sequence Completed

Background openvpn if you'd like:

     CTRL-Z
       [1]+  Stopped          sudo openvpn --config /etc/openvpn/air.ovpn
     bg
     sudo openvpn --config /etc/openvpn/air.ovpn &

I'm not sure how to start this automatically. Perhaps putting a small script in /etc/rc.conf.d/ would be appropriate. For security's sake I don't want to guess at it, since some VPN users can't risk leaking untunnelled data. Presumably it should start before any torrent clients, irc, etc.

### Troubleshooting

If you have a custom kernel, note that OpenVPN requires TUN/TAP modules enabled as described in OpenVPN. They should already work on default kernels.

I was setting this up on a virtual Arch system running in Virtualbox on a Windows 7 host machine. While testing I already had my Windows client tunnelling all traffic through my Windows AirVPN client. Trying to initialize a second tunnel from within the VM failed with an authentication failure, until I turned off the Windows client.

If the files are chmod 400, you must execute openvpn as superuser or it will fail with "Error opening configuration file."

See OpenVPN for lots more.

#### Sample configuration

Sample configuration profiles are included in `/usr/share/openvpn/examples/`, but here is one for reference:

    ##############################################
    ## Air VPN | https://airvpn.org | OpenVPN Client Configuration
    ##############################################

    client
    dev tun
    proto tcp
    remote 123.123.1.147 443
    resolv-retry infinite
    nobind
    persist-key
    persist-tun
    ca "ca.crt"
    cert "user.crt"
    key "user.key"
    ns-cert-type server
    cipher AES-256-CBC
    comp-lzo
    verb 3

Category:

- Virtual Private Network