Two Serial Links on 2600 router

[fruni]

Hi all,
I have a cisco 2621XM, with 2 serial links 1.5mbps and 512kpbs (se0/0 and se0/1).
I would like to use both the links simulteneously.

I have read that policy-based routing on cisco using route-map option works, but am not able to accomplish it.
It would be great if any one of you can help me out.

1. List out the pre-requisites for policy-based-routing

FYI: route-map policy

route-map BO-OUT permit 10
match ip address 1
set ip next-hop 202.56.198.105 (ISP1)
!
route-map BO-OUT permit 20
match ip address 2
set ip next-hop 61.246.208.181 (ISP2)
!

thanks,
Fruni

 

[jneiberger]

Why are you using Policy Based Routing? Why not simply use static routing and let the router load share like it normally would? You could also use EIGRP and its unequal load sharing feature so that the smaller link doesn't get overwhelmed.

John

 

[Cluebird]

Are there routes in the routing table to the next hop addresses? What you're trying to do usually requires BGP to give you the best performance. With the policy routing as you've implemented it you may be sending the traffic out but it is getting lost on the return. I doubt your ISPs will let you run EIGRP with them and static routing by itself will probably lead to suboptimal routing if you're not careful. However, you need to provide more information on what you're trying to do.

 

[nyy1023]

if you have two t-1's with the same provider I would recommend equal weight static routes.
ip route 0.0.0.0 0.0.0.0 s0.1
ip route 0.0.0.0 0.0.0.0 s1.1

This will also give you what you want and will do load SHARING across the lines. Keep in mind you will not have 3 Mb speed you still only have 2 1.5 lines. It will however appear to be faster because of sharing the load between two routes and the metrics the router uses.

 

[fruni]

Hi jneiberger (TechnicalUser),

The solution provided sounds accomplishable. Can you clarify on how to enable load sharing with two default routes on the cisco:

ip route 0.0.0.0 0.0.0.0 x.x.x.1 (isp-1)
ip route 0.0.0.0 0.0.0.0 x.x.x.1 (isp-2)


I have checked with this kind of setup, It will be difficult when you have VPN connections going out, as the return packet does no always return to the same ip from which it went out.

http browsing and other stuff is okay.

I would like to use the option similar to source based routing on a linux.

your valuelabe suggestions are most welcome.

regds,
Fruni

 

[jneiberger]

Why would the static route solution cause a problem with VPN connections? Are you using your serial interface IP addresses as endpoints for your tunnels? Can you use a routable loopback address instead?

If you use two static routes configured just as you suggest, you will automatically attain per-destination load sharing unless you've specifically turned on per-packet load sharing.

If you have CEF available, turn it on. If you don't, at least make sure you have fast switching enabled. If you have really long access lists on your external interfaces you could also try Netflow switching.

 

[Teecee33]

I need to do something similar to this but I will be using different ISP and some servers I use my PIX to give them a static outside IP on a specific line.