26.2. RIP External Routes filter table

The table of RIP External Routes contains information about filtering rules for routes which are external to the RIP domain and which could be imported into the RIP domain.

This table is used only when this router is declared as ASBR (ASBR:YES).

The table of RIP External Routes is used as follows:

  1. An empty table is a “default accept” table.

  2. A table with only “ignore” records is still a “default accept” table.

  3. A table with at least one “accept” record for a protocol becomes a “default ignore” for that protocol.

In the first case, the filtering is possible only “by protocol” (through the parameters LOCAL, STATIC and OSPF).

In the second case, routes are ignored.

In the third case, all the routes for the protocol having at least one “accept” record are ignored, except those explicitly accepted.

Commands for managing the table of RIP External Routes are the following:

26.2.1. D RIP EXTERNAL (Display RIP External Routes filter)

This command shows the content of the Table of RIP External Routes.

[17:20:03] ABILIS_CPX:d rip external

----------------------------------------------
EXTERNAL:            PROT:   ACTION:   METRIC:
----------------------------------------------
192.168.006.002/32   OSPF    ACCEPT          5
192.168.006.000/24   LOCAL   IGNORE          1
010.000.000.000/8    ANY     ACCEPT         10
000.000.000.000/0    ANY     ACCEPT          *
----------------------------------------------

Meaning of the parameters:

EXTERNAL

It specifies the external IP network that can be imported (or not) into RIP resource.

PROT

This parameter defines a routing protocol for which this filter will be applied [ANY, LOCAL, STATIC, OSPF];

ACTION

This parameter indicates if the selected network EXTERNAL can be accepted or ignored by RIP resource [IGNORE: do not distribute this IP addresses into RIP; ACCEPT: distribute this IP addresses into RIP]. This means that all the routing present in the IP Routings table which matches with EXTERNAL will be imported to RIP table in case that ACTION is set to ACCEPT (and then will be used also specified metric METRIC), and will be not imported in case that it is set to IGNORE.

METRIC

This parameter sets the metric value that will be used for redistribution routes, of LOCAL, STATIC or OSPF type, imported from the IP Routings table into RIP. The value * stands for “use default metric”.

The allowed syntax of the command is:

  • d rip external: it shows the table.

  • d rip external:x.x.x.x/yy PROT:val: it shows the specified entry.

26.2.2. A RIP EXTERNAL (Add RIP External Routes filter)

It adds a new entry to the Table of RIP External Routes.

The syntax of the command is:

a rip external:x.x.x.x/yy prot:val action:val [metric:val]

Example: add a rule for accept the RIP packets for the net 192.168.5.0/24 (static routing) and assign to it the exporting metric value 5.

[16:19:36] ABILIS_CPX:a rip external:192.168.5.0/24 prot:static action:accept metric:5

COMMAND EXECUTED

[16:19:39] ABILIS_CPX:d rip external

- Not Saved (SAVE CONF) -------------------------------------------------------

----------------------------------------------
EXTERNAL:            PROT:   ACTION:   METRIC:
----------------------------------------------
192.168.005.000/24   STATIC  ACCEPT          5
----------------------------------------------

26.2.3. C RIP EXTERNAL (Clear RIP External Routes filter)

It deletes the RIP external route entry identified by the specified mandatory parameters.

The syntax of the command is:

c rip external:x.x.x.x/yy prot:val

Example: clear the entry added in the previous paragraph.

[16:20:11] ABILIS_CPX:d rip external

- Not Saved (SAVE CONF) -------------------------------------------------------

----------------------------------------------
EXTERNAL:            PROT:   ACTION:   METRIC:
----------------------------------------------
192.168.005.000/24   STATIC  ACCEPT          5
----------------------------------------------

[16:21:41] ABILIS_CPX:c rip external:192.168.5.0/24 prot:static

COMMAND EXECUTED

[16:21:50] ABILIS_CPX:d rip external

- Not Saved (SAVE CONF) -------------------------------------------------------

----------------------------------------------
EXTERNAL:            PROT:   ACTION:   METRIC:
----------------------------------------------
    *** NO RIP EXTERNAL ROUTEs DEFINED ***

26.2.4. S RIP EXTERNAL (Set RIP External Routes filter)

It sets new values of the parameters of the RIP external route entry.

The syntax of the command is:

s rip external:x.x.x.x/yy prot:val par:val [par:val...]

Example: change the metric value to an already existing entry.

[16:28:38] ABILIS_CPX:d rip external

----------------------------------------------
EXTERNAL:            PROT:   ACTION:   METRIC:
----------------------------------------------
192.168.005.000/24   STATIC  ACCEPT          5
----------------------------------------------

[16:28:52] ABILIS_CPX:s rip external:192.168.5.0/24 prot:static metric:3

COMMAND EXECUTED

[16:29:13] ABILIS_CPX:d rip external

- Not Saved (SAVE CONF) -------------------------------------------------------

----------------------------------------------
EXTERNAL:            PROT:   ACTION:   METRIC:
----------------------------------------------
192.168.005.000/24   STATIC  ACCEPT          3
----------------------------------------------