IPv6 - 6in4 Tunnel
Contents
Introduction
6in4-tunnel rc.d script
Arch Linux uses a BSD-style network interface configuration located in /etc/rc.conf, which can make exotic network configurations interesting, to say the least. The following rc.d script is meant to help remedy the situation by providing a configurable wrapper to sanely manage a 6in4 link interface.
- This script uses the route2 method; make sure that the iproute2 package is installed.
As root, write the following rc.d init script to /etc/rc.d/6in4-tunnel:
#!/bin/bash ### begin user configuration ############################################## # # # Stop this script before you reconfigure! # # # ############################################## # if_name - interface name that is to be created for the 6in4 link if_name=6in4 # server_ipv4 - ipv4 address of the server that is providing the 6in4 tunnel server_ipv4=127.0.0.1 # client_ipv4 - ipv4 address of the client that is receiving the 6in4 tunnel client_ipv4=127.0.0.1 # client_ipv6 - ipv6 address of the client 6in4 tunnel endpoint client_ipv6=2001:feed:face:beef::2/64 # link_mtu - set the mtu for the 6in4 link link_mtu=1480 # tunnel_ttl - set the ttl for the 6in4 tunnel tunnel_ttl=64 ### end user configuration daemon_name=6in4-tunnel . /etc/rc.conf . /etc/rc.d/functions case "$1" in start) stat_busy "Starting $daemon_name daemon" ifconfig $if_name &>/dev/null if [ $? -eq 0 ]; then stat_busy "Interface $if_name already exists" stat_fail exit 1 fi ip tunnel add $if_name mode sit remote $server_ipv4 local $client_ipv4 ttl $tunnel_ttl ip link set $if_name up mtu $link_mtu ip addr add $client_ipv6 dev $if_name ip route add ::/0 dev $if_name add_daemon $daemon_name stat_done ;; stop) stat_busy "Stopping $daemon_name daemon" ifconfig $if_name &>/dev/null if [ $? -ne 0 ]; then stat_busy "Interface $if_name does not exist" stat_fail exit 1 fi ip link set $if_name down ip tunnel del $if_name rm_daemon $daemon_name stat_done ;; *) echo "usage: $0 {start|stop}" esac exit 0
6in4-tunnel configuration
You will need to provide your 6in4 link configuration between the following sections of /etc/rc.d/6in4-tunnel:
### begin user configuration
### end user configuration
Once /etc/rc.d/6in4-tunnel has been configured properly, give it permission to be executed:
# chmod +x /etc/rc.d/6in4-tunnel
6in4-tunnel usage
To create the 6in4 tunnel link and bring up the interface:
# /etc/rc.d/6in4-tunnel start
To delete the 6in4 tunnel link and remove the interface:
# /etc/rc.d/6in4-tunnel stop
Boot-time configuration
The following method allows /etc/rc.d/6in4-tunnel to start automatically at system startup.
- Verify that the 6in4 tunnel link is configured and working properly before doing this!
As root, insert 6in4-tunnel right after network in the DAEMONS line of /etc/rc.conf.
After this addition, the DAEMONS line in /etc/rc.conf should look something like this:
... # # ----------------------------------------------------------------------- # DAEMONS # ----------------------------------------------------------------------- # # Daemons to start at boot-up (in this order) # - prefix a daemon with a ! to disable it # - prefix a daemon with a @ to start it up in the background # DAEMONS=(syslog-ng iptables ip6tables network 6in4-tunnel openntpd ... ...