Critical - P2 
We (specifically, @john.morales) have observed an issue where the same metrics pings seem to be POSTed twice by the mongod, and at odd intervals. Specifically in this case, every minute at 45 seconds and 47 seconds past.
2018-06-17T15:25:45.636-0400 debug metrics /Users/johnmorales/projects/mms-free-monitoring-workspace/src/github.com/10gen/mms-free-monitoring/internal/metrics/service.go:33 Metrics request received from. {"rid": "MSA4NjBlNz"}
2018-06-17T15:25:47.007-0400 debug metrics /Users/johnmorales/projects/mms-free-monitoring-workspace/src/github.com/10gen/mms-free-monitoring/internal/metrics/service.go:33 Metrics request received from. {"rid": "MSA4NjBlNz"}
2018-06-17T15:26:45.652-0400 debug metrics /Users/johnmorales/projects/mms-free-monitoring-workspace/src/github.com/10gen/mms-free-monitoring/internal/metrics/service.go:33 Metrics request received from. {"rid": "MSA4NjBlNz"}
2018-06-17T15:26:47.018-0400 debug metrics /Users/johnmorales/projects/mms-free-monitoring-workspace/src/github.com/10gen/mms-free-monitoring/internal/metrics/service.go:33 Metrics request received from. {"rid": "MSA4NjBlNz"}
2018-06-17T15:26:50.780-0400 debug metrics /Users/johnmorales/projects/mms-free-monitoring-workspace/src/github.com/10gen/mms-free-monitoring/internal/metrics/service.go:33 Metrics request received from. {"rid": "MSA4NjBlNz"}
2018-06-17T15:27:45.664-0400 debug metrics /Users/johnmorales/projects/mms-free-monitoring-workspace/src/github.com/10gen/mms-free-monitoring/internal/metrics/service.go:33 Metrics request received from. {"rid": "MSA4NjBlNz"}
Our hunch is that either there are two POST threads running slightly out of sync, or two timers triggering the POSTs. This seems to happen indefinitely on the affected mongod, and never "fixes itself".
This issue has so far only happened once, and we haven't been able to reproduce it.