I am running MongoDB 4.4.2 cluster with one Primary, one Secondary and one hidden Secondary. On the hidden Secondary, sometimes (like once every 2 days or so) MongoDB just hangs (once it also happened on the Primary). By "hangs", I mean:

• I am not able to connect to mongod via mongoshell
• Secondary stops replicating, and starts lagging (until I restart it manually)
• but running `rs.status()` on the Primary server shows that hung Secondary is reachable

I referred to https://jira.mongodb.org/browse/SERVER-34190 which looked like a similar issue (but it was fixed in 3.6.4). So I have attached the files that were requested in that issue:

1. Output of the gdb command: gdb p $(pidof mongod) -batch -ex 'thread apply all bt' > gdb_`date +"%Y%m-%d_%H-%M-%S"`.txt
2. Last 500 lines of mongod.log
3. I have provided the latest files in diagnostic.data folder

Please let me know if you need anything else or you want me to try running some commands.