Recently, I registered IPv6 service for my home network from my ISP (i.e., HiNet). HiNet provides at least two ways to get the global IPv6 prefix.

1. Router Advertisement
2. DHCPv6 for Prefix Delegation

Prerequisite

In order to enable IPv6 in the LAN of my home gateway, the following packages must be installed at least:

• radvd
• wide-dhcpv6-client

PPPoE Configuration

Enable IPv6 for PPPD

Add the following lines in /etc/ppp/options:

local
ipv6 ,

Enable accept_ra for PPPoE

Add the following line in /etc/sysctl.conf

net.ipv6.conf.ppp0.accept_ra=2

Set to 2 when IPv6 forwarding is enabled.

Hook script

We need hook script to invoke the wide-dhcpv6-client after IPv6 is ready on PPP interface.

/etc/ppp/ipv6-up.d/wide-dhcpv6-client

#!/bin/sh

[ -x /etc/wide-dhcpv6/dhcp6c-ifupdown ] || exit 0

IFACE=$1
MODE=start

export IFACE MODE
/etc/wide-dhcpv6/dhcp6c-ifupdown

/etc/ppp/ipv6-down.d/wide-dhcpv6-client

#!/bin/sh

[ -x /etc/wide-dhcpv6/dhcp6c-ifupdown ] || exit 0

IFACE=$1
MODE=stop

export IFACE MODE
/etc/wide-dhcpv6/dhcp6c-ifupdown

DHCPv6-DP Configuration

/etc/wide/dhcpv6/dhcp6c.conf

interface ppp0 {
  #Request Prefix Delegation on ppp0, and give the received prefix id 0
  send ia-pd 1;
  script "/etc/wide-dhcpv6/dhcp6c-script-ppp0";
};

id-assoc pd 1 {
  prefix-interface br0 {
    sla-len 0;
    sla-id 1;
  };
};

Since HiNet only provides /64 prefix for DHCPv6-DP, the sla-len must be set to 0.

Hook script

We need hook script to restart radvd.

/etc/wide-dhcpv6/dhcp6c-script-ppp0

#!/bin/sh
systemctl restart radvd.service

Router Advertisement Configuration

Enable IPv6 forwarding

Add the following line in /etc/sysctl.conf

net.ipv6.conf.all.forwarding=1

/etc/radvd.conf

interface br0
{
   AdvSendAdvert on;
   #AdvLinkMTU 1492;
   prefix ::/64
   {
   };
   RDNSS 2001:b000:168::1 2001:b000:168::2
   {
   };
};