Currently, whenever an index build is kicked off on a replica set, it tends to trigger a "host is down" alert. Although this is benign and a false positive alert the on-call DBA has to wake up in the middle of a night when this alert pages us to make sure the host is NOT DOWN. When the monitoring agent tries to ping a node (where index build is running) and fails to communicate with it, it tends to think that the host is down and triggers this alert, although the host is up and running. When an index build is kicked off, it is capture in the mongodb.log. If monitoring agent can check the mongodb.log for an index build or somehow be notified that an index build is running on a node, so NOT to trigger a host is down, that would really help with all the false positive alerts that are being generated.