23.4. Examples of RIP configuration

In this section is described a typical example of RIP application.

Figure 23.1. RIP - Example

RIP - Example

The purpose is:

In the chart we find the following elements:

In this example is not required to analyze the kind of connection between the two sites.

In the following sections will be shown how to configure the Abilis of “Site 1”:

  1. Activation of RIP resources.

  2. Configuration of RIP resources.

  3. Configuration of IP and IP Router resources.

  4. Display IP routing tables.

In this example won't be necessary to use the RIP External Routes filter table: it means that the general rule will be “accept”.

23.4.1. Activation of RIP resources

Add the RIP resource on both Abilis of “Site1” with the following command; the RIP resource may already exist in the system, but may not yet be active: set it active with the command s act res:rip.

  • Abilis-1P:

    [15:43:30] ABILIS_1P:a res:rip
    
    RES:RIP ALREADY EXISTS
    
    [16:02:48] ABILIS_1P:s act res:rip
    
    COMMAND EXECUTED
    [Caution]Caution

    After adding or setting the RIP active, you must restart the Abilis to make the resource running (use the command warm start to reboot the Abilis).

    [11:01:39] ABILIS_CPX:s p rip act:yes
    
    COMMAND EXECUTED
    
    [11:01:39] ABILIS_CPX:d p rip
    
    RES:Rip - Not Saved (SAVE CONF), Not Refreshed (INIT) -------------------------
           ------------------------------------------------------------------------
    Run    DESCR:Routing_Information_Protocol
           LOG:NO      ACT:YES  locport:520  fifo:15  max-routes:500    SH:PR
           AUT:NO      PWD:                  UT:30    LT:180   GT:120   ASBR:YES
           - ASBR section ---------------------------------------------------------
           LOCAL:YES           STATIC:YES           OSPF:NO
           LOCAL-METRIC:*      STATIC-METRIC:*      OSPF-METRIC:*
           DEF-METRIC:1
  • Abilis-1B:

    Repeat the same procedure for Abilis-1B.

23.4.2. Configuration of RIP resources

  • Abilis-1P:

    Abilis-1P is the Abilis that manage the primary link to Abilis2, so its metric default value must be the lowest one: it will be leaved to default value 1. So, on this Abilis is enough to enable the resource.

  • Abilis-1B:

    Abilis-1B is the Abilis that manage the backup link to Abilis-2, so its metric default value must be higher the Abilis-1P one: it will be set to the value 3.

    [11:01:39] ABILIS_CPX:s p rip def-metric:3
    
    COMMAND EXECUTED
    
    [11:01:39] ABILIS_CPX:d p rip
    
    RES:Rip - Not Saved (SAVE CONF), Not Refreshed (INIT) -------------------------
           ------------------------------------------------------------------------
    Run    DESCR:Routing_Information_Protocol
           LOG:NO      ACT:YES  locport:520  fifo:15  max-routes:500    SH:PR
           AUT:NO      PWD:                  UT:30    LT:180   GT:120   ASBR:YES
           - ASBR section ---------------------------------------------------------
           LOCAL:YES           STATIC:YES           OSPF:NO
           LOCAL-METRIC:*      STATIC-METRIC:*      OSPF-METRIC:*
           DEF-METRIC:3

    With this command we have assigned to all the IP routings of Abilis-1B the metric value 3, so they will be exported with this cost.

23.4.3. Configuration of IP resources

Now indicating on which IP resources the RIP protocol is to be active is needed.

The Abilis-1P and Abilis-1B are connected on the same Ethernet LAN, so we have to active RIP on the correspondent IP resources (res:ip-1).

The parameters which must be set are:

RP

It's used to activate/deactivate routing protocols on this interface; when RIP protocol is selected, the specific parameter section will be activated.

RIPSEND

It sets the protocol used for sending RIP updates [RIP1, RIP2B, NO];

RIPRECV

It sets the protocol accepted for receiving RIP updates [RIP1, RIP2, BOTH, NO];

RIPNU (normal update)

It sets whether RIP updates have to be sent regularly or only in case of variations;[NO: updates are sent only if the routing table is changed,YES: updates are sent regularly according to the RIP resource];

RIPMETRIC

It sets the metric associated to IP port according to meant and the rules prescribed by the routing algorithm RIP.

  • Abilis-1P:

    [09:37:33] ABILIS_1P:s p ip-1 rp:rip
    
    COMMAND EXECUTED
    
    [09:37:45] ABILIS_1P:d p ip-1
    
    RES:Ip-1  - Not Saved (SAVE CONF), Not Refreshed (INIT) ------------------------
    Run    DESCR:
           OPSTATE:UP             IPLOG:NO
           LANRES:Eth100-1
           IPADD:192.168.001.254  MASK:255.255.255.000
           REDIS:YES          HIDE:NO          RP:RIP
           NAT:NO             IPSEC:NO         DIFFSERV:NO          VRRP:NO
           OUTBUF:100         OUTQUEUE:FAIR    MTU:1500             BRD:NET
           OUTSPL:NO
           INBUF:0                             mru:1500             SRCV:NO
           - RIP section ----------------------------------------------------------
           RIPSEND:RIP2B      RIPRECV:BOTH     RIPNU:YES            RIPMETRIC:1
           - TRFA section ---------------------------------------------------------
           TRFA:NO
           - Lan ------------------------------------------------------------------
           LOG:NO             arpcache:200     CACHETIMER:120
           rxbuf:4            txbuf:14
    RES:Eth100-1 ------------------------------------------------------------------
    Run    DESCR:
           LOG:NO            MODE:AUTO         DUPLEX:HALF   TPPOL:AUTO
           dma-rxbuf:250     dma-txbuf:25      ip-rxbuf:25   arp-rxbuf:5
           pppoed-rxbuf:5    pppoes-rxbuf:25   ieee-rxbuf:25
  • Abilis-1B:

    [09:37:33] ABILIS_1B:s p ip-1 rp:rip
    
    COMMAND EXECUTED
    
    [09:37:45] ABILIS_1B:d p ip-1
    
    RES:Ip-1  - Not Saved (SAVE CONF), Not Refreshed (INIT) ------------------------
    Run    DESCR:
           OPSTATE:UP             IPLOG:NO
           LANRES:Eth100-1
           IPADD:192.168.001.253  MASK:255.255.255.000
           REDIS:YES          HIDE:NO          RP:RIP
           NAT:NO             IPSEC:NO         DIFFSERV:NO          VRRP:NO
           OUTBUF:100         OUTQUEUE:FAIR    MTU:1500             BRD:NET
           OUTSPL:NO
           INBUF:0                             mru:1500             SRCV:NO
           - RIP section ----------------------------------------------------------
           RIPSEND:RIP2B      RIPRECV:BOTH     RIPNU:YES            RIPMETRIC:1
           - TRFA section ---------------------------------------------------------
           TRFA:NO
           - Lan ------------------------------------------------------------------
           LOG:NO             arpcache:200     CACHETIMER:120
           rxbuf:4            txbuf:14
    RES:Eth100-1 ------------------------------------------------------------------
    Run    DESCR:
           LOG:NO            MODE:AUTO         DUPLEX:HALF   TPPOL:AUTO
           dma-rxbuf:250     dma-txbuf:25      ip-rxbuf:25   arp-rxbuf:5
           pppoed-rxbuf:5    pppoes-rxbuf:25   ieee-rxbuf:25
    [Caution]Caution

    To initialize the resources, use the init res:ip-1 command (to set act the changes made on uppercase parameters) and remember to save the configuration to preserve the modifications (save conf).

23.4.4. Configuration of IP Router

It's important take a look also to the IP router configuration:

[10:44:33] ABILIS_1P:d p iprtr

RES:Iprtr ---------------------------------------------------------------------
       DESCR:IP_Router_general_properties
       - General --------------------------------------------------------------
       R-ID:AUTO (192.168.001.254)
       maxroute:500       DFTTTL:64           ps:2048
       DEF-LOCAL-AD:0     DEF-STATIC-AD:1     DEF-OSPF-AD:110   DEF-RIP-AD:120
       pvc:0              bsvc:0              LINKS:1           virtual:0
       - IP Access List -------------------------------------------------------
       ACL:NO                 ACLBYPASS:#
       COS:DISABLED           COSDFT:NORMAL
       COSBALANCE:NO          NORMRATE:50            LOWRATE:50
       - IP Trace -------------------------------------------------------------
       tracerec:100
       - Ppp-Dns --------------------------------------------------------------
       PPP-DNS-PRI:000.000.000.000  PPP-DNS-SEC:000.000.000.000

The parameter DEF-RIP-AD sets the default value of the Administrative Distance for the routes received from RIP.

The parameter DEF-LOCAL-AD sets the default value of the Administrative Distance for local-connected routes.

When IPRTR gets routing from different routings protocol, must give them a specific priority. This parameter can be overridden in case of current routing is present in administrative distance table.

By joining this two parameters it's possible to complete configurations: the DEF-LOCAL-AD parameter on Abilis-1B will have a higher value than the Abilis-1P's one, so that the local-connected routes of Abilis-1B will have the lowest priority.

Remember that the aim is to ensure automatic switch to backup connection between two remote sites. When primary link is down, the Abilis-1B must inform Abilis-1P that the better way to reach the “Site2” is through it, but during the normal working Abilis-1B must know that the way to reach the “Site2” is through Abilis-1P.

On Abilis-1B:

[11:15:43] ABILIS_1B:s p iprtr DEF-LOCAL-AD:180

COMMAND EXECUTED

[11:50:30] ABILIS_1B:d p iprtr

RES:Iprtr - Not Saved (SAVE CONF), Not Refreshed (INIT) -----------------------
       ------------------------------------------------------------------------
       DESCR:IP_Router_general_properties
       - General --------------------------------------------------------------
       R-ID:AUTO (192.168.001.253)
       maxroute:500       DFTTTL:64           ps:2048
       DEF-LOCAL-AD:180   DEF-STATIC-AD:1     DEF-OSPF-AD:110   DEF-RIP-AD:120
       pvc:0              bsvc:0              LINKS:1           virtual:0
       - IP Access List -------------------------------------------------------
       ACL:NO                 ACLBYPASS:#
       COS:DISABLED           COSDFT:NORMAL
       COSBALANCE:NO          NORMRATE:50            LOWRATE:50
       - IP Trace -------------------------------------------------------------
       tracerec:100
       - Ppp-Dns --------------------------------------------------------------
       PPP-DNS-PRI:000.000.000.000  PPP-DNS-SEC:000.000.000.000
[Caution]Caution

To initialize the resources, use the init res:iprtr command (to set act the changes made on uppercase parameters) and remember to save the configuration to preserve the modifications (save conf).

23.4.5. Display IP routing tables

Now let see what happens in the routing tables of the two Abilis when functioning on primary link and backup link.

This will be the routings table when primary link is active.

[12:46:18] ABILIS_1P:d ipr

Destination routes and conditional source routes:
+-+-+-+-+--------------------+--------------------+-----------------+----+---+
|B|P|S|H|     NET:/MASK:     |      MASK: or      |       GW:       |IP: |AD:|
| | | | |                    |   SRNET:/SRMASK:   |                 |    |   |
+-+-+-+-+--------------------+--------------------+-----------------+----+---+
|*|R| | | 192.168.001.253/32 | 255.255.255.255    | 192.168.001.253 |   1|120|
|*|C| | | 192.168.001.254/32 | 255.255.255.255    |                 |R-ID|  0|
|*|C| | | 192.168.001.000/24 | 255.255.255.000    |                 |   1|  0|
|*|C| | | 192.168.002.000/24 | 255.255.255.000    |                 |   5|  0|
|*|S| | | 000.000.000.000/0  | 000.000.000.000    |                 |   3|  1|
+-+-+-+-+--------------------+--------------------+-----------------+----+---+
[14:26:47] ABILIS_1B:d ipr

Destination routes and conditional source routes:
+-+-+-+-+--------------------+--------------------+-----------------+----+---+
|B|P|S|H|     NET:/MASK:     |      MASK: or      |       GW:       |IP: |AD:|
| | | | |                    |   SRNET:/SRMASK:   |                 |    |   |
+-+-+-+-+--------------------+--------------------+-----------------+----+---+
|*|C| | | 192.168.001.253/32 | 255.255.255.255    |                 |R-ID|180|
|*|R| | | 192.168.001.254/32 | 255.255.255.255    | 192.168.001.254 |   1|120|
|*|C| | | 192.168.001.000/24 | 255.255.255.000    |                 |   1|  0|
|*|R| | | 192.168.002.000/24 | 255.255.255.000    | 192.168.001.254 |   1|120|
| |C| | | 192.168.002.000/24 | 255.255.255.000    |                 |   5|180|
|*|R| | | 000.000.000.000/0  | 000.000.000.000    | 192.168.001.254 |   1|  1|
+-+-+-+-+--------------------+--------------------+-----------------+----+---+

In this situation Abilis-1B receives from Abilis-1P the route for the Site2's network (192.168.2.0/24): the priority of this route is higher than the route local-connected, so the RIP route will be considered the best.

Otherwise, this will be the routing table when backup link is operating.

[12:46:18] ABILIS_1P:d ipr

Destination routes and conditional source routes:
+-+-+-+-+--------------------+--------------------+-----------------+----+---+
|B|P|S|H|     NET:/MASK:     |      MASK: or      |       GW:       |IP: |AD:|
| | | | |                    |   SRNET:/SRMASK:   |                 |    |   |
+-+-+-+-+--------------------+--------------------+-----------------+----+---+
|*|R| | | 192.168.001.253/32 | 255.255.255.255    | 192.168.001.253 |   1|120|
|*|C| | | 192.168.001.254/32 | 255.255.255.255    |                 |R-ID|  0|
|*|C| | | 192.168.001.000/24 | 255.255.255.000    |                 |   1|  0|
|*|R| | | 192.168.002.000/24 | 255.255.255.000    | 192.168.001.253 |   1|120|
| |C| | | 192.168.002.000/24 | 255.255.255.000    |                 |D  5|  0|
|*|S| | | 000.000.000.000/0  | 000.000.000.000    |                 |   3|  1|
+-+-+-+-+--------------------+--------------------+-----------------+----+---+
[14:26:47] ABILIS_1B:d ipr

Destination routes and conditional source routes:
+-+-+-+-+--------------------+--------------------+-----------------+----+---+
|B|P|S|H|     NET:/MASK:     |      MASK: or      |       GW:       |IP: |AD:|
| | | | |                    |   SRNET:/SRMASK:   |                 |    |   |
+-+-+-+-+--------------------+--------------------+-----------------+----+---+
|*|C| | | 192.168.001.253/32 | 255.255.255.255    |                 |R-ID|180|
|*|R| | | 192.168.001.254/32 | 255.255.255.255    | 192.168.001.254 |   1|120|
|*|C| | | 192.168.001.000/24 | 255.255.255.000    |                 |   1|  0|
|*|C| | | 192.168.002.000/24 | 255.255.255.000    |                 |   5|180|
|*|R| | | 000.000.000.000/0  | 000.000.000.000    | 192.168.001.254 |   1|  1|
+-+-+-+-+--------------------+--------------------+-----------------+----+---+

In this situation Abilis-1P receives from Abilis-1B the route for the Site2's network (192.168.2.0/24): the IP resource 5 on Abilis-1P is declared down (D 5), so the correspondent route won't be sent by RIP; the RIP route will be considered the best, so the packets for the remote network will be sent through Abilis-1B.

In this way (supposing that Abilis-1P is the default gateway for the network 192.168.1.0/24), the users in Site1 could reach the Site2's network through the backup link, without change anything on their terminals!