1Since 2.3.0, OpenVPN officially supports IPv6, and all widely used
2patches floating around for older versions have been integrated.
3
4IPv6 payload support
5--------------------
6
7This is for "IPv6 inside OpenVPN", with server-pushed IPv6 configuration
8on the client, and support for IPv6 configuration on the tun/tap interface
9from within the openvpn config.
10
11The code in 2.3.0 supersedes the IPv6 payload patches from Gert Doering,
12formerly located at http://www.greenie.net/ipv6/openvpn.html
13
14
15The following options have been added to handle IPv6 configuration,
16analogous to their IPv4 counterparts (--server <-> --server-ipv6, etc.)
17
18     - server-ipv6
19     - ifconfig-ipv6
20     - ifconfig-ipv6-pool
21     - ifconfig-ipv6-push
22     - route-ipv6
23     - iroute-ipv6
24
25see "man openvpn" for details how they are used.
26
27
28
29IPv6 transport support
30----------------------
31
32This is to enable OpenVPN peers or client/servers to talk to each other
33over an IPv6 network ("OpenVPN over IPv6").
34
35The code in 2.3.0 supersedes the IPv6 transport patches from JuanJo Ciarlante,
36formerly located at http://github.com/jjo/openvpn-ipv6
37
38OpenVPN 2.4.0 includes a big overhaul of the IPv6 transport patches
39originally implemented for the Android client (ics-openvpn)
40
41IPv4/IPv6 transport is automatically is selected when resolving addresses.
42Use a 6 or 4 suffix to force IPv6/IPv4:
43
44  --proto udp6
45  --proto tcp4
46  --proto tcp6-client
47  --proto tcp4-server
48  --proto tcp6 --client / --proto tcp6 --server
49
50On systems that allow IPv4 connections on IPv6 sockets
51(all systems supporting IPV6_V6ONLY setsockopt), an OpenVPN server can
52handle IPv4 connections on the IPv6 socket as well, making it a true
53dual-stacked server. Use bind ipv6only to disable this behaviour.
54
55On other systems, as of 2.3.0, you need to run separate server instances
56for IPv4 and IPv6.
57