node1# more /etc/rc.conf
[...]
ipv6_enable="YES"
ipv6_gateway_enable="YES"
ipv6_network_interfaces="lo0 igb0 em0 vlan1 vlan101 vlan102 carp0 carp1 carp2"
ipv6_defaultrouter="::1"

ipv6_ifconfig_igb0="fdcb:9921:3552:afd6::2 prefixlen 64"
ipv6_ifconfig_em0="fdcb:9921:3552:afff::2 prefixlen 64"
ipv6_ifconfig_vlan1="fdcb:9921:3552:afd7::2 prefixlen 64"
ipv6_ifconfig_vlan101="fdcb:9921:3552:afd8::2 prefixlen 64"
ipv6_ifconfig_vlan102="fdcb:9921:3552:afd9::2 prefixlen 64"
ipv6_ifconfig_carp0="fdcb:9921:3552:afd6::1 prefixlen 64"
ipv6_ifconfig_carp1="fdcb:9921:3552:afd8::1 prefixlen 64"
ipv6_ifconfig_carp2="fdcb:9921:3552:afd9::1 prefixlen 64"
[...]
pf_enable="YES"
pf_flags=""
pf_rules="/etc/fw.conf"
pfsync_enable="YES"
pfsync_syncdev="em0"
[...]

Pour la configuration IPv4, c’est par ici.