The default configuration of the DHCPv6 client works fine in the most cases. However, to configure a DHCP client manually, create and modify the
/etc/dhcp/dhclient.conf file. See the
/usr/share/doc/dhclient-4.1.1/dhclient6.conf.sample for a client configuration file example.
For advanced configurations of DHCPv6 client options such as protocol timing, lease requirements and requests, dynamic DNS support, aliases, as well as a wide variety of values to override, prepend, or append to client-side configurations, see the
dhclient.conf(5) man page and the
STANDARD DHCPV6 OPTIONS section in the
dhcpd-options(5) man page.
In Red Hat Enterprise Linux 6, a DHCPv6 client is correctly handled only by NetworkManager and should not generally be run separately. That is because DHCPv6, unlike DHCPv4, is not a standalone network configuration protocol but is always supposed to be used together with router discovery.