IPv6 in OpenWRT
First make sure your internet provider has IPv6 support.
OpenWRT configuration
In OpenWRT setup add or edit interface "wan6" interface (beside regular wan for IPv4).
Protocol: DHCPv6 client Bring up on boot: checked Request IPv6-address: try
keep your existing IPv4 br-lan, add a new interface br6 (or set other name) as Bridge:"br-lan" with IPv6 static address.
IPv6 address: fdc2:2cf8:e49b::1/64 IPv6 gateway: copy IPv6 from wan6
IPv6 DHCP server
You may need isc-dhcp-server-ipv6 package for IPv6 DHCP server support.
configure IPv6 DHCP server for br6
Interface -> lan -> DHCP Server -> IPv6 Settings Designated master: not checked RA-Service: server mode DHCPv6-Service: server mode NDP-Proxy: hybrid mode Learn routes: checked
https://your_openwrt_ip/cgi-bin/luci/admin/network/network
Global network options IPv6 ULA-Prefix: fdc2:2cf8:e49b::/64
NAT rule for IPv6
You may need to a NAT rule for IPv6
https://your_openwrt_ip/cgi-bin/luci/admin/network/firewall
Name: ipv6forwawrd Restrict to address family: IPv6 only Procol: Any Outbound zone: wan Source address: any Destination address: any Action: MASQUERATE - Automatically
or add it manually using ip6tables-extra package (example: wlan eth0.2)
# ip6tables -t nat -A POSTROUTING -o eth0.2 -j MASQUERADE
source: https://forum.openwrt.org/t/how-to-use-ipv6-nat/100516/3
Add IPv6 supported DNS server in your "/etc/resolv.conf" and test ping6
$ ping6 ipv6_supported_domain_name
If you face routing issue you may try:
# sysctl -w net.ipv6.conf.wlanX.accept_ra=2 or dpending on your interface # sysctl -w net.ipv6.conf.eth0/2.accept_ra=2
for debugging you may use
# sysctl -a | grep net.ipv6 | grep accept_ra
If it works modify sysctl config
vi /etc/sysctl.d/10-default.conf
Linux network configuration example
/etc/network/interfaces
...
iface eno1 inet manual
auto br0
iface br0 inet static
bridge_ports eno1
address 192.168.0.103
broadcast 192.168.0.255
netmask 255.255.255.0
gateway 192.168.0.1
dns-nameservers 192.168.0.1
iface br0 inet6 static
address fdc2:2cf8:e49b::103
netmask 64
gateway fdc2:2cf8:e49b::1
If you are using Gnome network manager.
IPv6 Method: Manual Address: fdc2:2cf8:e49b::103 Prefix: 64 Gateway: fdc2:2cf8:e49b::1
Now, you will be able to access IPv6 supported websites.