Static route.

[speculor_cisco]

I have noted that, when I add a static route, if I put the exit interface, the static route is always added to the route table.

Instead, if I put the next hop, it seems that the router checks if it can reach that next hop.

If it is so, it adds the route, otherwise it does not add the route.

Is it true? Thanks.

[krahmani323]

Hello,

Indeed certain conditions must be met before a static route is written into the route  table (also when specifying a static route with an exit interface) :

- IP routing must be enabled

- As you noticed, the next-hop address, if used, must be  reachable.

- The exit interface must have an IP address configured on it, and the  exit interface must be up.

Regards.

Karim

[speculor_cisco]

While I remembered the other two conditions, I had some doubts about the reachability of the next hop.

May be I had already read this third condition, but I did not remember the book.

So I have prefered to ask here for less loss of time.

Thanks for your good answer.

[Gregory Camp]

If you specify a next-hop with a static route, the route is installed as long as we have a valid route for that next-hop in the routing table (i.e. connected interface, IGP route, etc).  Does the next-hop have to respond to ARP requests, ICMP, etc. no, but it does need to be in the RIB.

[ROGER FERNANDO MAJO ZACARIAS]

Hola.

Debes tener presente lo siguiente:

1. para que una ruta estatica sea anunciada o propagada usando el protocolo de ruteo correspondiente (RIP,, BGP, OSPF, ETC) dentro de la configuracion del protocolo de ruteo debe existir el comando: redistribute static o redistribute static route-map xxx.
2. este comando: redistribute static, redistribuye toda ruta estatica que configures en el router sin excepcion.
3. si usas la opcion route-map, esta opcion te permite seleccionar que rutas estaticas deseas propagar.

Espero que halla sido de ayuda la informacion.

Si deseas mayor detalle, avizame.

Attn.