Different bandwidth on Interface and EIGRP Metric

Rupesh Kashyap · ‎04-22-2009

Hi, I have 10 Mbs internet connectivity on the router, running BGP. I have EIGRP for internal network. I have redistributed Bgp into Eigrp with Bandwidth 5 Mbs, but I have made QOS on 10 Mbs on the outside interface. What would be effect of this ? Is this create any problem or bandwidth mismatch?

Talha Ansari · ‎04-22-2009

The bandwidth 5 mbps which you have entered in the redistribute command is different than the throughput of your link. The actual throughput would be 10 mbps which is provided by your service provider and eigrp uses the interface bandwidth for calculation of its metric not the throughput.

The default bandwidth on your fastethernet is 100000 kilobits.

As far as QoS is concerned I don't think this would create any issue.

Thanks,

Rupesh Kashyap · ‎04-22-2009

got it sir.

Giuseppe Larosa · ‎04-22-2009

Hello Rupesh,

these two parameters are unrelated and don't interact.

the BW value you have used in redistribution is used to create the seed metric for routes redistributed from BGP into EIGRP.

Notice that the actual value used in this case is not important until there is single node that redistribute into EIGRP.

The bandwidth command under the interface is used as a reference by QoS objects that use a percent command.

It is very important that this value reflects the real speed of the link for QoS to work well.

Hope to help

Giuseppe