Choosing the predetermined path

[demon_ir80]

Hi.
I have encountered a problem, and I would appreciate it if you could tell me what to do. According to the diagram, we have two PCs, and I want each of them, if they want to ping routers RA4 and Router5, to take different paths.
It means PC 0 wants to ping the router with IP 172.16.1.3 and send the packet to Router RA2.
And similarly, PC 0 wants to ping 172.16.1.4, but this time, only send the packet to RA3.
The routing protocol on the routers is OSPF, and it's active in Area 0.
The Layer 3 switch also has an active VLAN that connects the routers RA2-4, and OSPF is active on them as well.

[MHM Cisco World · Accepted solution]

can you use different process or you must use one OSPF process ?

Thanks A Lot
MHM 

[demon_ir80]

just ospf

[M02@rt37 · Accepted solution]

Hello @demon_ir80,

To achieve different paths for PC0 to ping routers RA4 and RA5, you can use policy-based routing 'PBR' on the Layer 3 switch that connects the PCs and routers.

For PC0 to ping Router RA4 (172.16.1.4) via Router RA2:

ip access-list extended PC0-RA4
permit ip host PC0-IP host 172.16.1.4

route-map PBR-RA4 permit 10
match ip address PC0-RA4
set ip next-hop Router-RA2-IP

interface VLANX # The VLAN interface connecting PC0
ip policy route-map PBR-RA4

For PC0 to ping Router RA5 (172.16.1.3) via Router RA3:

ip access-list extended PC0-RA5
permit ip host PC0-IP host 172.16.1.3

route-map PBR-RA5 permit 10
match ip address PC0-RA5
set ip next-hop Router-RA3-IP

interface VLANX # The VLAN interface connecting PC0
ip policy route-map PBR-RA5

--This configuration will direct traffic from PC0 to the desired routers based on the destination IP address, allowing you to achieve different paths for pinging RA4 and RA5.

[demon_ir80]

can you fix That?

[luis_cordova]

Hola

Hasta donde se, en PT no se puede configurar PBR.

Lo que solicitas se puede lograr en PT configurando rutas estáticas a las IP de destino que indicas, apuntando como siguiente salto a los router  para el camino deseado.

RA1(config)#ip route 172.16.1.3 255.255.255.255 192.168.1.2

RA1(config)#ip route 172.16.1.4 255.255.255.255 192.168.2.2

Con eso los paquetes tomaran el camino deseado.(esto sucede porque las rutas estáticas tienen un AD menor a OSPF y son elegidos como mejor camino en la tabla de ruteo).

Espero que esto te sea de utilidad.

Saludos

[demon_ir80]

Hi, thanks for the help
What if I want to implement inside EVE-NG?Does eve-ng support?
Because in that environment, I RUN the router's own IOS
Ty

[luis_cordova]

Hola

Claro, en EVE-NG o en GNS3 se puede lograr configurar PBR, pues los dispositivos corren el IOS completo, no el IOS emulado de Packet Tracer.

Saludos

[M02@rt37]

Hello @demon_ir80 

Thanks for sharing your PT project.

Like I suggest to you in private, PBR is not available on PT ; PT has limitations in the IOS of the devices.

On RA1, route /32 (host) directly  to the desired next-hop: