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New Member

Auto cost reference bandwidth for OSPF

Hi!

I am currently troubleshooting netwotk performance issue on a LAN/WAN project i recently completed. This network is using OSPF with LAN interface running at 10/100/GE and WAN 64K to E1. I am using default cost reference bandwitdh without changing it to 10000 because there are some GE interface on the LAN side? Aside from slow/unreliable link, would this affect the network performance? Apreciate your expert advice. Thanks.

Rgds

Helme

  • WAN Routing and Switching
2 REPLIES

Re: Auto cost reference bandwidth for OSPF

Hi

I would suggest to use the auto-ref command under your ospf config otherwise u may face some issues in traffic flow on the slow speed links like E1/64K since the ospf process will have the same cost calculated for those link irrespective of their bandwidth.(coz of higher bandwidth reference in the N/W)...by default the ref b/w is 100Mbps and since u have mentioned about the existence of high b/w links better to key in the reference b/w..

This is the default behaviour since you have 10G and 1G links in ur network..

regds

New Member

Re: Auto cost reference bandwidth for OSPF

Hi!

Thanks for your help. I have tested this out and confirm our suspicion for quite sometime. Without adjusting the ref bandwidth we did notice funny thing in the routing table. Already put this on the production router and notice considerable improvement :). Thanks.

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