express-mongo-crud | Express middleware for mongo crud APIs | Runtime Evironment library

[Edit]

Sorry my bad, the connections string mongodb://mongodb:27017 would actually work. I tried dns querying that name, and it was able to resolve to the correct ip address even without specifying ".default.svc...".

root@web-controller-mlplb:/app# host mongodb mongodb.default.svc.cluster.local has address 10.108.119.125

@Anshul Jindal is correct that you have race condition, where the web pods are being loaded first before the database pods. You were probably doing kubectl apply -f . Try doing a reset kubectl delete -f . in the folder containing those yaml . Then kubectl apply the database manifests first, then after a few seconds, kubectl apply the web manifests. You could also probably use Init Containers to check when the mongo service is ready, before running the pods. Or, you can also do that check in your node.js application.

Example of waiting for mongodb service in Node.js

In your connection.js file, you can change the connect function such that if it fails the first time (i.e due to mongodb service/pod not being available yet), it will retry again every 3 seconds until a connection can be established. This way, you don't even have to worry about load order of applying kubernetes manifests, you can just kubectl apply -f .