OSPF feature needed

[zhichao]

Hi

In the ospf network, the default cost for VLAN interfaces is 1. We have used 'auto-cost reference-bandwidth 10000' to change the cost to 10. Can this value be configured to reflect the real bandwidth?

For example, if we have a GE channel consists of 2 links in this VLAN. We hope when both of the links are up, the cost should be 5 (since there are 2 GEs). When one of the link is down, the cost should be 10.

Pls enlight me if there is a way to achieve this.

[mark-obrien]

Your GE channel should appear as an ether-channel interface in your router. If so, you can manually set the bandwidth of that interface to reflect double the GE bandwidth, and OSPF should adjust the cost accordingly.

HTH

Mark

[zhichao]

Hi

We are using a layer 3 switch, and we did not use the GE channel as a layer 3 port (because there are other vlans running on this GE channel, so we have to configure it to be 802.1Q trunking port). Instead we configured the layer 3 routing using Interface VLANs. The OSPF does not adjust the cost for VLAN interfaces.

thanks

[mark-obrien]

Have you tried changing the configured bandwidth of the VLAN interface?

Mark

[ruwhite]

As far as I know, there's no way to automatically adjust the bandwidth of any channelized link to reflect the number of channels up or down. We've talked about this as a feature for a while, but I don't think it's available at the moment on any channelized interface.

:-)

Russ.W

[zhichao]

thanks!

Pls do add this in the future.

[ruwhite]

Send me an email off line, and I'll work on seeing what sort of support we have (number of customers/etc), and what the chances are of getting into code.

:-)

Russ.W

riw@cisco.com