LMS 4.0 GRE Tunnel Utilization is too high, inconsistent with expected value

canero · ‎03-01-2011

Hello,

We are using Ciscoworks LMS 4.0 inorder to monitor the bandwidth usage and utilization of the GRE Tunnel Interfaces. The bandwidth usage in terms of bytes/sec is consistent with the show interface bits/sec for the input and output values.

As the utilization graph is concerned, the physical interface utilization shows ok, i.e. if 1Mbps traffic is output on a fastethernet interface it shows 1% Utilization. The formula used for Utilization calculation is: (tx octets * 8 *100)/ifspeed.

Ifspeed value is simple for the physical interfaces to guess and it is correct. For the tunnel GRE interfaces, the SnmpWalk through the interfaces shows that the ifspeed value is 100 000 for the tunnel interfaces. Is this value configurable through CLI configuration or LMS through snmpset?

We want to see 100% utilization at 2048kbps (2Mbps), for the GRE tunnel utilization, currently the values show between 80% and 300%, which is not rational for us.

Thanks in Advance,

Best Regards,

A similar problem is as follows:

http://forums.cacti.net/about35566.html&highlight=

Joe Clarke · ‎03-12-2011

You can use the "bandwidth" command under the tunnel inteface to set the proper ifSpeed. What you describe is a common problem with tunnels. If you adjust bandwidth to be the proper speed, your utilization calculations will be correct.