Technical data

4. Packages
addresses which will not work if the host part is not 64 bits. If the self-configuration fails
the subnet prefix should be checked for incorrect length (for example as /48).
Default setting: IPV6_NET_1_ADVERTISE='yes'
IPV6_NET_x_ADVERTISE_DNS This variable determines whether the local DNS service
in IPv6 subnets should be advertised by “Router Advertisements”. This will only works
if the IPv6 functionality of the DNS service is activated using DNS_SUPPORT_IPV6=’yes’.
Possible values are “yes” and “no”.
Default setting: IPV6_NET_1_ADVERTISE_DNS='no'
IPV6_NET_x_DHCP This variable enables the DHCPv6 service for this IPv6 subnet. Pos-
sible values are “yes” and “no”. DHCPv6 will only be used to provide informations on
domain names and address of the used DNS server to hosts in this subnet. The assign-
ment of IPv6 addresses via DHCPv6 is currently not possible with fli4l.
The address of the DNS server is published via DHCPv6 only if the IPv6 support of the
DNS service is enabled via DNS_SUPPORT_IPV6 in package dns_dhcp.
Important: The variables IPV6_NET_x_ADVERTISE_DNS and IPV6_NET_x_DHCP do not ex-
clude each other and can both be enabled. In this case the address of the DNS server can
be queried in two ways by hosts on the local network.
Per network interface a maximum of one bound IPv6-subnet can be config-
ured for DHCPv6!
Default setting: IPV6_NET_1_DHCP='no'
IPV6_NET_x_NAME (optional) This variable specifies an interface-specific hostname for
the router in this IPv6-subnet.
Example: IPV6_NET_1_NAME='fli4l-subnet1'
Tunnel Configuration
This section introduces the configuration of 6in4 IPv6 tunnels. Such a tunnel is useful in case
that your own ISP does no support IPv6 natively. With an internet host of a tunnel broker
known as a PoP (Point of Presence) a bi-directional link via IPv4 can be established. All
IPv6 packets will be routed encapsulated (therefore 6 “in” 4 because of the IPv6 packets are
encapsulated in IPv4 packets).
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First the tunnel will be established and in a second step
the router is configured in a way that the IPv6 packets to the Internet are routed through the
tunnel. The first part is covered in this section and the second part is described in the next
section.
IPV6_TUNNEL_N This variable contains the number of 6in4 tunnels to be established.
Example: IPV6_TUNNEL_N='1'
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This is known as IPv4 protocol 41, “IPv6 encapsulation”.
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