Docker Ignores limits.conf (trying to solve “too many open files” error)

Question

I\'m running a web server that is handling many thousands of concurrent web socket connections. For this to be possible, on Debian linux (my base image is google/debian:wheezy,

Answer 1

With docker-compose you could configure ulimits.

https://docs.docker.com/compose/compose-file/#ulimits

You can add soft/hard limits as a mapping.

ulimits:
  nproc: 65535
  nofile:
    soft: 20000
    hard: 40000

Although not ideal you could run container with privileged option (Mostly for a quick non-optimal solution for a Dev environment, not recommended if security is a concern).

docker run --privileged

Please see:

https://docs.docker.com/engine/reference/run/#runtime-privilege-and-linux-capabilities