I seem to have the same issue.

All is well, however, after some days, A query operations Find(xxx) failed with errors as below:

connection(192.168.20.194:3717[-123425]) incomplete read of message header: read tcp 10.233.26.252:47192->192.168.20.194:3717: use of closed network connection

and the following query operations, such as a lot of Operations Find(xxx),  failed with errors like these:

context deadline exceeded

there is no one connection between my-server and mongo-server when I type command `netstat -apn`.

Then I tried to capture tcp package by tcpdump.  also no one tcp package occured.