From 53c6274071f4adab870dfc4173d1815287d65464 Mon Sep 17 00:00:00 2001 From: sven-ola Date: Wed, 13 Oct 2010 18:20:19 +0000 Subject: git-svn-id: https://map66.svn.sourceforge.net/svnroot/map66@26 3484d885-4da6-438d-b19d-107d078dd756 --- README.txt | 28 ++++++++++++++++++++++++++-- 1 file changed, 26 insertions(+), 2 deletions(-) (limited to 'README.txt') diff --git a/README.txt b/README.txt index 9ea1734..399a38a 100644 --- a/README.txt +++ b/README.txt @@ -18,6 +18,10 @@ Configuration Detailed Version IPv6/IPv4 Precedence + + Change gai.conf + Use 6to4 Internal Address + Motivation These files implement a Linux netfilter target that changes the IPv6 address of @@ -202,9 +206,10 @@ pre-installed /etc/gai.conf file will give you a hint on this. In short: the getaddrinfo() library function rates a private IPv4 address higher than the ULA IPv6 address when choosing the transport protocol for a new Internet connection if this add on to the RFC 3484 rules is compiled in. For -this reason, you may want to change the precedence rules within /etc/gai.conf. +this reason, you may want to change the precedence rules within /etc/gai.conf +(see Change gai.conf) or use another prefix (see Use 6to4 Internal Address). -Note +Change gai.conf The getaddrinfo() library function manages lists of label, precedence, and scope4 type entries. If the /etc/gai.conf file does not provide a single entry @@ -230,6 +235,25 @@ The above procedure removes the difference between standard IPv6 source addresses and ULA type private IPv6 source addresses. Anything else is unchanged. +Use 6to4 Internal Address + +As an alternative solution, you may use 6to4 addresses in your LAN. While the +well known IPv4 adresses 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16 still +exist, it is unlikely that their 6to4 counterparts 2002:0a00::/24, 2002:ac10::/ +28, and 2002:c0a8::/32 will be routed on the Internet. Because 6to4 adresses +are part of the official 2002::/3 address prefix for the Internet, no +difference between these addresses and other Internet addresses are made by +getaddrinfo(). + +If you already deployed ULA adresses in your network, you may be interested in +a solution that runs on my Freifunk router. The router uses the IPv4 +192.168.65.65/26 on it's LAN interface. WIthin the OLSR-based mesh network, any +interface uses an fdca:ffee:babe::/64 prefix. The following internal mapping is +configured for this: + +ip6tables -t mangle -I PREROUTING -i br0 -s 2002:c0a8:4141::/64 -j MAP66 --src-to fdca:ffee:babe::/64 --unbalanced +ip6tables -t mangle -I POSTROUTING -o br0 -d fdca:ffee:babe::/64 -j MAP66 --dst-to 2002:c0a8:4141::/64 --unbalanced + Motivation My Internet access at home is realized by a wireless community mesh network not -- cgit v1.2.3