I was hoping I could get the support of the community for Solarwinds to revisit how they calculate the interface bandwidth of xDSL interfaces specifically ADSL.
As you know there are many variations of xDSL and the one I am focusing on is Asymmetric Digital Subscriber Loop. I have identified that Solarwinds calculates the speeds incorrectly and assumes that the interface would be Symmetric which in most cases is incorrect when dealing with ADSL.
From the image below this shows the interface "Bandwidth" which is calculated by NPM using the OID IfSpeed [from what I can find out on Thwack] using this OID only provides the UPSTREAM of an interface and not the DOWNSTREAM sync rate that you would expect for the 'Receive' value..
After a little playing with the UNDP I came across the following OID that calculates the ACTUAL interface speed for ADSL interfaces for downstream.
Using the present configuration NPM is unable to report on utilization correctly as you see over 100% as the actual bandwidth is far greater than the calculated speeds of the interface.
I am aware that I am able to configure manual bandwidth statements but this becomes a management nightmare as DSL is rate adaptive so this could change on a daily basis.. we currntly monitor more than 1500+ DSL interfaces on a variety of equipment.
Thanks for reading.L