On some Linux distribution, IPv6 networking may be enabled by default, however, if IPv6 networking is not enabled by default the following configuration is needed to enable IPv6 networking.
Enabling IPv6 on a Linux host(CentOS)
To enable IPv6 networking, the host's network configuration file needs to be edited and a network restart must be administered.
pc#vi /etc/sysconfig/network //edit network file on the host machine
NETWORKING_IPV6=yes //change the networking field from "no" to "yes"
pc#service network restart // Restart the network on the host
Note: When IPv6 networking is enabled IPv6, autoconfiguration is enabled by default. If you do not wish to use autoconfiguration, append the following like to /etc/sysconfig/network :
IPV6_AUTOCONF=no
Configuring Linux to forward IPv6 packets
To configure Linux to forward IPv6 traffic issue the following commands:
sysctl -w net.ipv6.conf.all.forwarding=1sysctl -w net.ipv6.conf.default.forwarding=1
Configuring IPv6 routing table on Linux
Adding routes:
route -A inet6 add <prefix> gw <next hop>
ip -6 route add <prefix> via <next hop>
route -A inet6 add ::/0 gw <next hop> // Add a default (::/0) route.
ip -6 route add ::/0 via <next hop>
Showing routes:
route -A inet6
ip -6 route show dev eth0
Assigning IPv6 temporary address(privacy extensions) on a Linux host(CentOS)
To generate a privacy address and not use it as the preferred address do the following:
pc#sysctl net.ipv6.conf.all.use_tempaddr=1
pc#sysctl net.ipv6.conf.default.use_tempaddr=1
pc#service network restart
To generate a privacy address and use it as the preferred address do the following:
pc#sysctl net.ipv6.conf.all.use_tempaddr=2
pc#sysctl net.ipv6.conf.default.use_tempaddr=2
Displaying neighbor tables
To display neighbor tables (equivalent of IPv4 ARP tables):
ip -6 neigh show [dev <device>]
