Every 2-4 weeks I get (111: Connection refused) while connecting to upstream. Why?

I have a rails app that uses Nginx and Puma. Every 2-4 weeks my app starts giving 502 errors. When digging into log files, this is the error that comes up

[error] 8353#8353: *38966 connect() to unix:///home/deploy/apps/later_backend/shared/tmp/sockets/later_backend-puma.sock failed (111: Connection refused) while connecting to upstream, client:, server:, request: "GET / HTTP/1.1", upstream: "http://unix:///home/deploy/apps/later_backend/shared/tmp/sockets/later_backend-puma.sock:/", host: "", referrer: ""

A restart will fix the issue but I’m getting really sick of my app crashing every 2-4 weeks and having to do a manual restart. Amy thoughts on what this could be?

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What is your Droplet size? It could be that app gets killed due to it ran out of memory. Syslog could give you more information on that. Open it with your favorite text editor:

  1. sudo nano /var/log/syslog

Look at it, and if you see any Out Of Memory entry for your app, it was killed because it ran out of RAM.

In that case Droplet upgrade is recommend. You can add Swap space as alternative to upgrade. Because it is only after 2-4 weeks, you could have memory leaks somewhere. That means that app is not releasing used memory. This is something you have to find in source code if it’s available.

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