I have a node.js app with mongodb backend going to production in a week and i have few doubts on how to handle app crashes and restart . Say i have a simple route /followUser in which i have 2 database operations /followUser ----->Update User1 Document.followers = User2 ----->Update User2 Document.followers = User1 ----->Some other mongodb(via mongoose)operation What happens if there is a server crash(due to power failure or maybe the remote mongodb server is down ) like this scenario : ----->Update User1 Document.followers = User2 SERVER CRASHED , FOREVER RESTARTS NODE What happens to these operations below ? The system is now in inconsistent state and i may have error everytime i ask for User2 followers ----->Update User2 Document.followers = User1 ----->Some other mongodb(via mongoose)operation Also please recommend good logging and restart/monitor modules for apps running in linux