20.4. Administrative Distance

20.4. Administrative Distance
	Chapter 20. IPRTR - IP Router

Administrative distance lets Abilis to select the best path when there are two or more different routes towards the same destination;the route with the lowest value of AD has the highest priority into the IP routing table.

The Administrative Distance table contains information about the rules for routes priority into IP Routing table. The commands for managing the IP Routing Administrative Distances table are the following:

d ipad
a ipad
c ipad
s ipad

20.4.1. D IPAD (Display IP Administrative Distance)

Use d ipad command to display the parameters of the resource. By typing d ipad ? command it's possible to display the meaning of all the parameters.

[10:49:13] ABILIS_CPX:d ipad

+--------------------+---------+-----------+---------+
|        NET:        |  PROT:  | DISTANCE: |   IP:   |
+--------------------+---------+-----------+---------+
| 192.168.006.002/32 |  RIP    |      110  |         |
| 192.168.006.000/24 |  RIP    |      120  |         |
| 192.168.006.000/24 |  OSPF   |      100  |         |
| 010.000.000.000/8  |  STATIC |       10  |   NONE  |
| 000.000.000.000/0  |  LOCAL  |        5  |         |
+--------------------+---------+-----------+---------+

Meaning of the parameters:

NET: It indicates the destination network IP address and the mask used for setting administrative distance, in Slash Notation (i.e. x.x.x.x/yy).
PROT: This parameter defines a routing protocol for which this distance will be applied.[NONE, LOCAL, STATIC, OSPF, RIP]
DISTANCE: This parameter defines the distance that will be used for route priority into IP Routing table.
IP: This parameter defines the IP resource value. It's allowed only when PROT parameter is set to STATIC. [NONE: no IP resource; *: all IP resources; 1..250: it's used the specified IP resource].

20.4.2. A IPAD (Add IP Administrative Distance)

This command adds a new entry into the IP Routing Administrative distance table. To display the syntax of the command, type a ipad ?.

Here an example.

[17:22:54] ABILIS_CPX:a ipad net:0.0.0.0/0 prot:static distance:180 ip:4

COMMAND EXECUTED

[17:22:54] ABILIS_CPX:d ipad

- Not Saved (SAVE CONF), Not Refreshed (INIT) ---------------------------------

+--------------------+---------+-----------+---------+
|        NET:        |  PROT:  | DISTANCE: |   IP:   |
+--------------------+---------+-----------+---------+
| 000.000.000.000/00 | STATIC  |    180    |     4   |
+--------------------+---------+-----------+---------+

	Caution
	Changes made on the IP Routing Administrative distance table are NOT immediately active, they can be activated by executing the initialization command init ipad.

[14:00:15] ABILIS_CPX:a ipr net:0.0.0.0/0 gw:192.168.0.254 ip:4 -fd

COMMAND EXECUTED

[14:01:01] ABILIS_CPX:d ipr

Destination routes and conditional source routes:
+-+-+-+-+--------------------+--------------------+-----------------+----+---+
|B|P|S|H|     NET:/MASK:     |      MASK: or      |  GW: or IPLB:   |IP: |AD:|
| | | | |                    |   SRNET:/SRMASK:   |                 |    |   |
+-+-+-+-+--------------------+--------------------+-----------------+----+---+
|*|C| | | 080.080.080.080/32 | 255.255.255.255    |                 |R-ID|  0|
|*|C| | | 192.168.000.000/24 | 255.255.255.000    |                 |   1|  0|
|*|C| | | 192.168.005.000/24 | 255.255.255.000    |                 |   3|  0|
|*|S| | | 000.000.000.000/0  | 000.000.000.000    |                 |   2|  1|
| |S| | | 000.000.000.000/0  | 000.000.000.000    | 192.168.000.254 |   4|180|
+-+-+-+-+--------------------+--------------------+-----------------+----+---+

	Note
	The option “`-fd`” has been used because a static routing towards network 0.0.0.0/0 was already present.

The “Best” route for network 0.0.0.0/0 is the IP-2 resource; the alternative way it's the IP-4 resource that will be considered only if the primary route is down. In normal conditions the route towards IP-4 resource is ignored.

20.4.3. C IPAD (Clear IP Administrative Distance)

This command deletes the specified entry from the IP Routing Administrative distance table, if it's present. To display the syntax of the command type c ipad ?.

Here's an example.

[18:11:52] ABILIS_CPX:c ipad net:0.0.0.0/0 prot:static distance:180 ip:4

COMMAND EXECUTED

[18:12:11] ABILIS_CPX:d ipad

- Not Saved (SAVE CONF), Not Refreshed (INIT) ---------------------------------

+--------------------+---------+-----------+---------+
|        NET:        |  PROT:  | DISTANCE: |   IP:   |
+--------------------+---------+-----------+---------+
*** NO IP ROUTING ADMINISTRATIVE DISTANCEs DEFINED ***

	Caution
	Changes made on the IP Routing Administrative distance table are NOT immediately active, they can be activated by executing the initialization command init ipad.

20.4.4. S IPAD (Set IP Administrative Distance)

This command sets the parameters of the selected entry on the IP Routing Administrative Distances table. To display the syntax of the command type s ipad ?.

[18:11:52] ABILIS_CPX:s ipad net:0.0.0.0/0 ip:5

COMMAND EXECUTED

[18:12:11] ABILIS_CPX:d ipad

- Not Saved (SAVE CONF), Not Refreshed (INIT) ---------------------------------

+--------------------+---------+-----------+---------+
|        NET:        |  PROT:  | DISTANCE: |   IP:   |
+--------------------+---------+-----------+---------+
| 000.000.000.000/00 | STATIC  |    180    |     5   |
+--------------------+---------+-----------+---------+


20.3. IP Resources		20.5. IP Load Balancing