Subsections

3.9 Network prefix configuration

OPT_NET_PREFIX
Enables support for custom network prefixes.

A network prefix is technically nothing else than the address of a network, but it usually stands for a network that shall be divided further. This is especially useful if a fli4l router should not manage the whole network, but leave subnets for other routers. By the definition (and thus naming) of the whole network it is possible to use the network address in several places without always having to write the prefix again.

Concrete examples of how to define a network prefix can be found below for the different types of network prefixes.

Defaul Setting: OPT_NET_PREFIX='yes'

NET_PREFIX_x

This array defines the various network prefixes. The individual components are explained below.

NET_PREFIX_x_NAME
Name of the network prefix.

This variable contains the name of the prefix. This name can then be used in address informations in order to use the prefix. The name has to be set like circuit names, i.e. it must be specified in curly brackets.

NET_PREFIX_x_TYPE
Type of the network prefix.

This variable contains the type of the prefix. The supported types are explained in Tab. 3.3.

Table 3.3: Types of network prefixes
Typw Explanation
   
static The network prefix is specified directly as a fixed address.
generated-ula The network prefix is generated by fli4l as an ULA3.2 according to RFC 4193.3.3 If the fli4l has access to persistent storage, then the prefix is only generated once, so it also remains intact during reboots of the router.
 

3.9.1 Network prefixes of type ``stable''

For network prefixes of type ``stable'' the following settings apply:

NET_PREFIX_x_STATIC_IPV4 NET_PREFIX_x_STATIC_IPV6
Adresse(s) of the network prefix.

This setting can be used to specify the IPv4 and/or IPv6 address of the network prefix.

Example:

    NET {
      PREFIX {
        [] {
          NAME='site'
          TYPE='static'
          STATIC {
            IPV4='10.1.0.0/16'
            IPV6='fdce:1c35:301f::/48'
          }
        }
      }
    }

3.9.2 Network prefixes of type``generated-ula''

For Network prefixes of type ``generated-ula'' the following settings apply:

NET_PREFIX_x_ULA_DEV
Ethernet-Interface.

This setting specifies the Ethernet interface whose MAC address is used to generate the ULA.

Example:

    NET {
      PREFIX {
        [] {
          NAME='site'
          TYPE='generated-ula'
          ULA {
            DEV='eth0'
          }
        }
      }
    }



Footnotes

... ULA3.2
``Unique Local Address''
... 4193.3.3
https://tools.ietf.org/html/rfc4193
© 2001-2022 The fli4l-Team - 19 August 2022