Load Balance on 4 E1 Serial Links across 2 routers

cisco_realm · ‎08-26-2008

hi,

There are several ways of configuring load balancing of outbound traffic on a single router with multiple links such as per-packet, per-destination, CEF etc.

However, is there any way by which 4 E1 lines divided across two routers (i.e. two each) can be load balanced on outbound traffic?.

Rgds.

Giuseppe Larosa · ‎08-26-2008

Hello Arif,

if the two routers have only client LAN interfaces all in common you can use GLBP if the clients are many it can provide host based load sharing.

GLBP reference

http://www.cisco.com/en/US/docs/ios/ipapp/configuration/guide/ipapp_glbp.html

If the routers act as border routers and there are other routers inside in a common LAN what you need is a routing protocol like OSPF or EIGRP where both routers have to advertise the same destinations with identical metric and metric-type including the special case of a default-route if needed.

Hope to help

Giuseppe

Joseph W. Doherty · ‎08-26-2008

Besides Giuseppe's recommendation for GLBP, depending on the routing protocol you're using, starting from one router, you might be able to make the other router's outbound paths appear equal cost.

Or, if your routers are running a recent enough IOS with the correct feature set, you may be able to run OER or PfR to dynamically load balance outbound traffic. At the moment, believe only static or OER routing supported.