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New Member

Load Balancing 4 T1s

Hey all,

I just had 4 T1s installed on my campus, typically I would use PPP Multilink to load balance the 4 Ts using a virtual interface with one IP address.

This order, the provider gave me an ip address on each T. So right now I have 4 T1s on 4 different /30 networks. Is there a good way to load balance these with this configuration?

Thank you,



Re: Load Balancing 4 T1s

Yes, you could layer3 load balancing across the 4T1s. You can use a static/dynamic routing to acheive this. Load balancing type - per packet/destination/session - will be determined by the ingress interface switching type selection.

Let me know if you have any questions.




Re: Load Balancing 4 T1s

One way to do this is have the router loadbalance with equal cost IP routes pointing to each far end IP address on the T1's.

For example, if this was an internet connection I would do the following:

ip route

ip route

ip route

ip route

Make sure you have CEF enabled: 'ip cef'

With this the router, by default, will loadbalance over each T1 on a per flow basis, not per-packet.

Please rate all helpful posts.



New Member

Re: Load Balancing 4 T1s

what if i want to use only one for http and others for others traffics

Re: Load Balancing 4 T1s

you should do PBR for the http traffic to go only through the 4th link (while perform load-balancing on the other 3 links - don't put any static routes on the 4th link)

route-map http_traffic

match ip address 101

set intrerface serial <4th link>

access-list 101 permit tcp any any eq www

and finaly apply the route-map under the internal Ethernet interface using the "ip policy route-map http_traffic"

hope this helps

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