Why am I seeing receive/transmit utilization higher than 100%?

Question

I searched through the forum to see if I could find an answer to this but gave up after several pages of results with CPU in the subject. Hope someone can help....

When I look at the Top 10 summary page I see that I have a server talking to a Cisco switch with either transmit or receive utlilzation higher than 100%. How is this possible?

I checked the interface in Orion on the Windows server and it is a HP NC371i Multifunction Gigabit Server Adapter with a transmit and receive bandwidth of 1000000000.

What am I missing? I thought the space shuttle was the only thing that could throttle up to 120%....

Karlo.Zatylny · Answer

Our interface traffic calculations are prone to slight errors depending for a couple of reasons.  The way we calculate is to get the octet count at each polling interval and finding the delta of both the octet counts and time between polls (accurate to the amount of time between the polling of that specific OID from that specific device).  Some customers have had success in making their polling interval shorter.

Also it is possible that some devices update the octet count before the actual sending of a packet which might throw the calculations off a little. RTT to the device also may throw off the calculations if the device is "far away".

You should not see utilization more than a few percent off.  If you are, then call support and reference this thread.

Thanks

njoylif · Answer

Nuclear reactors can go above 100% as well - 110 or 115 redline I think...bad... :)
Unfortunately, I don't have any worthwile comment to make, except that on routers, it takes the bandwidth statement, but switches are a different beast. How much traffic is actually passing through the interface? 10% of reported?  Does Orion show the interface as Gig or 100MB?

FormerMember · Answer

Bump.....