Bandwidth Speeds

Question

I have a Cisco Catalyst 6500 with the 720 Supe card. I would like to get the upload and download utilization of a specific port. I would like it from SNMP, I have looked for the correct MIB but no luck. The port I am trying to see is gi2/23.

Answer 1

A quick-and-dirty way to get the current utilization would be to poll these OIDs from OLD-CISCO-INTERFACES-MIB:

• locIfInBitsSec - 1.3.6.1.4.1.9.2.2.1.1.6.x
• locIfInPktsSec - 1.3.6.1.4.1.9.2.2.1.1.7.x
• locIfOutBitsSec - 1.3.6.1.4.1.9.2.2.1.1.8.x
• locIfOutPktsSec - 1.3.6.1.4.1.9.2.2.1.1.9.x

These give you the same numbers as the "input rate" and "output rate" lines from the output of show interface. Just replace the "x" with the interface index for Gig2/23 shown in show snmp mib ifmib ifindex. The MIB states that it's the "five minute exponentially-decayed moving average", but the actual rate matches whatever you've configured with load-interval on the interface (which defaults to 5 minutes).

These OIDs will give you a pretty good point-in-time measurement of the interface's utilization without requiring an external system to keep track of deltas between measurements. However, since it's an exponentially-decayed moving average, it may not be as accurate.