Solved: Policy routing

akaliptos · ‎03-24-2007

Hello,

I am having a hard time with policy routing.

There is a 1841 router having 2 WAN connections (aDSL), each with different ISP.

What I am trying to do originate traffic from each fastethernet to different dialer an vice versa.

Let's say di0<->fa0/0 & di1<->fa0/1.

Imagine two different LANs, each using its own WAN connection.

Till now I have:

interface FastEthernet0/1

ip address x.y.z.a 255.255.255.248

ip policy route-map ROUTEMAPNAME

access-list 101 permit ip x.y.z.0 0.0.0.7 any

route-map ROUTEMAPNAME permit 1

match ip address 101

set interface dialer1

Thanks in advance

Richard Burts · ‎03-24-2007

Stavros

It seems to me that your Policy Based Routing should work with either set interface or set next-hop.

If you want to direct all traffic coming into fa0/0 to go to dialer 0, all traffic coming into fa0/1 to go to dialer 1, all traffic coming into dialer 0 to go to fa0/0 and all traffic coming into dialer 1 to go to fa0/1 then you will need ip policy configured on all 4 interfaces.

While the parts of config that you posted look ok, you have not indicated whether that part is working or not. Perhaps you can clarify.

I would also like to ask a clarifying question: is it possible that a packet could arrive at dialer1 with a destination address on fa0/0? If that did happen what would you do? Your statement of requirements seems to indicate that you would forward it to fa0/1 anyway. Is this an accurate statement of requirements?

There was a discussion in NetPro a while back about something similar to this situation and suggestion made that perhaps VRF lite might be a way to get the results that you want - almost like 2 separate routers in the same box. Perhaps you can think about this alternative.

HTH

Rick

HTH

Rick

View solution in original post

royalblues · ‎03-24-2007

Friend,

Let me know if i understand your requirement here.

You want the traffic from Fa0/1 to exit via Dialer1 and fa 0/0 via dialer0

You should better use the next hop ips in this case.

Configure 2 LAN pools corresponding to the LAN pool.

USe route-maps and instead of set interface use set ip next-hop of the dialer interfaces.

Narayan

akaliptos · ‎03-24-2007

I need all traffic originating behind fa0/1 to be routed via dialer1, as well as all inbound traffic to dialer1 to be forwarded to fa0/1.

As if there are 2 routers (di0-fa0/0 & di1-fa0/1).

Richard Burts · ‎03-24-2007

Stavros

It seems to me that your Policy Based Routing should work with either set interface or set next-hop.

If you want to direct all traffic coming into fa0/0 to go to dialer 0, all traffic coming into fa0/1 to go to dialer 1, all traffic coming into dialer 0 to go to fa0/0 and all traffic coming into dialer 1 to go to fa0/1 then you will need ip policy configured on all 4 interfaces.

While the parts of config that you posted look ok, you have not indicated whether that part is working or not. Perhaps you can clarify.

I would also like to ask a clarifying question: is it possible that a packet could arrive at dialer1 with a destination address on fa0/0? If that did happen what would you do? Your statement of requirements seems to indicate that you would forward it to fa0/1 anyway. Is this an accurate statement of requirements?

There was a discussion in NetPro a while back about something similar to this situation and suggestion made that perhaps VRF lite might be a way to get the results that you want - almost like 2 separate routers in the same box. Perhaps you can think about this alternative.

HTH

Rick

HTH

Rick

akaliptos · ‎03-24-2007

Of course!!! On all interfaces, as well as remove the default route (this is what I was missing!)

Thank you, your post "unstuck" me!

Regards,

Stavros

Richard Burts · ‎03-24-2007

Stavros

I am glad that my post was able to help you to find the solution to your issue. And thanks for the rating. The forum is a very helpful place to discuss problems and to find solutions. I encourage you to continue your participation in the forum.

HTH

Rick

HTH

Rick