traffic to take same path bi-directional path.

[army27]

I am having a problem with my network. Since my network if almost fully meshed. The traffic takes 1 path going from router A to router B. But on the way back the traffic goes from router C to router B to router A.

I need for my traffic to go back and forth using the same path.

any help will be appreciated.

 

[ccbootcamp]

What's happening is called Asymmetric routing. You need to check your path's to and from each device. What routing protocol are you using? If you are using EIGRP (which is my first guess) then make sure you have the correct bandwidth command issued on each interface. I took over a credit union's network that had MAJOR EIGRP issues. The consultant that did the intial install had redundant FR paths, used EIGRP, and never configured any bandwidth commands on the interfaces...bad bad bad.

-brad Network Learning Inc

http://www.ccbootcamp.com

http://www.routerie.com

 

[dnels]

You may also want to check the default gateways of the devices that are sending traffic via RTRC. This could cause a problem if you are using HSRP because is turns off IP REDIRECT. Someone could be using an invalid default gateway address or the active HSRP address could be in a less than optimal spot.

Dave

 

[army27]

Bootcamp, you are correct we do use EIGRP for routing and Dnels we are using HSRP on the end routers. As for the bandwidth command my path goes like this. router A goes to Router B at 32K, router b has at least 2 paths one of them is 128K. I still want my packet to go back through the 32K pipe. As for the bandwith do I use the bandwidth 32 in router A and bandwidth 32 in router B that is how i have it configured, but the packet wants to go through the 128K pipe.

any advice.

 

[dnels]

I don't think I understand your configuration. Your path one way is:

RTRa == 32k == RTRb ==> somewhere

On the return trip you get:

Somewhere ==> RTRc == Some connection == RTRb == 32k ==RTRa

You want:

Somewhere ==> RTRb == 32k == RTRa

What is the connection from RTRc to RTRb?
Is the destination network directly attached to RTRb and RTRc?
Is the detination network also directly connected to RTRc?
Where is the 128k circuit?

Dave

 

[army27]

Ok, let me try to explain. RouterA which has HSRP configured. goes to router B. Router B is a core router which has multiple connections to other routers. The path that the packet takes from router A to router B can have multiple paths. Which is OK. I just need for the packet to go back and forth along the same path.

When a ping is sent to router B from A it takes 1 path but on the return trip it takes another path. the reason is because router A has a 32K pipe to router B but router B has multiple paths to get back to the device. on the return trip there is another link through a VSAT. Which the router thinks it has 128K but unfortunatly since it is VSAT it has an inherent delay of 1/4 second per trip. Even thogh you have more bandwidth. The ping takes much longer.

 

[dnels]

So router b and router a have multiple paths a 32K path and a VSAT path?

 

[dnels]

So, if you sho ip route to rtrb on rtra the best path is via the 32k path, or are there multiple equal cost paths?

And the same sho ip route to rtra on rtrb show what?

You could always punish the 128k circuit by manipulating the bandwidth or the delay on the interface but you need to be sure you don't need to use this path for an optimal route to some other network. If you do you may have to be a little deterministic in how you manipulate the routing metrics.

Dave