New Cacti bandwidth graphs will be appearing for some customers

Hi, TL;DR version: A few customers will see new bandwidth graphs appearing in their Cacti, which can be found at https://tools.bitfolk.com/cacti/ The already-existing graphs will continue to run for a while and then will cease to be updated. The new graph will become your primary bandwidth graph. This is because some high-bandwidth users need to have graphs based on 64-bit counters, not 32-bit, in order to accurately measure bandwidth use. It may result in slightly higher values being reported in Cacti, but this is merely correcting previous under-reporting. Monthly totals as presented in our emailed data transfer reports were/are correct. Longer version: While investigating some recent discrepancies between the different systems we have for accounting for customer data transfer, I discovered that all of our bandwidth graphs were using 32-bit SNMP counters. A 32-bit unsigned counter has a maximum value of 4,294,967,295. With 5 minute sampling, that means that an interface seeing around 114Megabit/sec of traffic will reach 4,294,967,295 and wrap around to zero again before the counter can be read. As a result, a few customers who routinely use large amounts of bandwidth have Cacti graphs that are under-reporting their usage. Here is an example of a graph based on 32-bit counters: http://tools.bitfolk.com/cacti/graph_5062.html Here is the same interface graphed from 64-bit counters: http://tools.bitfolk.com/cacti/graph_5617.html You can see that the first daily graph has several drop-outs around high bandwidth periods, and that the total data transferred in the last 24 hours is under-reported in the first daily graphs. I will not go through and replace every bandwidth graph with new ones, only those of customers who are seen to be transferring more than ~4.2GB in 5 minutes. So if you see a new graph appearing, this is why. Measuring 32-bit counters on a 2x 1 gigabit interface was of course a very silly oversight, and it is now apparent that even the virtual network device in an individual VPS has no problem exceeding ~114Mbit/s. Cheers, Andy -- http://bitfolk.com/ -- No-nonsense VPS hosting