Refresh net.core.somaxcomm (or any sysctl property) for docker containers

Question

I am trying to change net.core.somaxconn for docker container to be able to have larger queue of requests for my web application.

On OS, outside docker, I first modify the property successfully:

$ cat /proc/sys/net/core/somaxconn
128
$ sudo sysctl -w net.core.somaxconn=1024
net.core.somaxconn = 1024
$ cat /proc/sys/net/core/somaxconn
1024

But then I don't know how to propagate that change into docker. I've tried:

• Also editing /etc/sysctl.conf (in hope of docker reading that file on container launch)
• Restarting containers sudo docker stop and sudo docker run again
• Restarting the whole docker service by sudo service docker restart

But inside container, cat /proc/sys/net/core/somaxconn always shows 128.

I'm running docker 1.2 (so I cannot, by default, modify /proc attributes inside container) and in Elastic Beanstalk (so without --privileged mode, that would allow me to modify /proc).

How can I propagate the sysctl changes to docker?

Answer 1

Just figured out how to solve this, now Elastic Beanstalk supports running a privileged containers and you just need to add the "privileged": "true" to your Dockerrun.aws.json as the following sample (please take a look at the container-1):

{
  "AWSEBDockerrunVersion": 2,
  "containerDefinitions": [{
    "name": "container-0",
    "essential": "false",
    "image": "ubuntu",
    "memory": "512"
  }, {
    "name": "container-1",
    "essential": "false",
    "image": "ubuntu",
    "memory": "512",
    "privileged": "true"
  }]
}

Please note that I duplicated this answer from another thread.