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Confirm load balancing operation ?!? - How ?


I have set up GLBP on 2 routers I have in a test lab. One is a serial back to back running at 192k and the second is isdn2e running at 128k.

The HSRP side of the operation ( i.e. failover etc )is working well but when I pass traffic over the interfaces using an IP traffic generator the throughput only ever reaches either 192k if the primary router is passing the data or 128k if the secondary is. I have confirmed this by reviewing the graphed outputs of the IP generating application

I would expect the load balancing to kick in and see the throughput rise towards 400k but this does not occur.

I have tried all three types of load balancing with GBLP but to no avail.

How can I check the operation of the load balancing ( which I am sure is not working ) and what should I be looking for in order to fix this?

Note: I have set up basic GLBP using the Cisco config guide and the routers are running ospf. I have already tried setting equal ospf costs for the outgoing interfaces but this did not work.

Any hints/tips/guesses/advice greatly appreciated,




Re: Confirm load balancing operation ?!? - How ?


with GLBP every host on a LAN segment still gets a single MAC for the default gateway. Loadsharing is achieved by giving different MACs to different clients. In case there is only one client the router getting ALL it´s packets will do normal routing towards the destination. With OSPF the best route wins an entry into the IP routing table and is used.

So: have at least two clients and make both WAN lines equal cost as a start. Or use EIGRP with variance.

Hope this helps


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