how to set ulimit / file descriptor on docker cont

Question

I need to set the file descriptor limit correctly on the docker container I connect to container with ssh (https://github.com/phusion/baseimage-docker)

Already tried:

• edit limits.conf the container ignore this file
• upstart procedure found at https://coderwall.com/p/myodcq but this docker image has different kind of init process. (runit)
• I tried to modify configuration of pam library in /etc/pam.d
• try to enabled pam for ssh in sshd_config

The output it always the same.

bash: ulimit: open files: cannot modify limit: Operation not permitted

Answer 1

Here is what I did.

set ulimit -n 32000 in the file /etc/init.d/docker

and restart the docker service

docker run -ti node:latest /bin/bash

run this command to verify

user@4d04d06d5022:/# ulimit -a

should see this in the result

open files (-n) 32000

[user@ip ec2-user]# docker run -ti node /bin/bash
user@4d04d06d5022:/# ulimit -a
core file size          (blocks, -c) 0
data seg size           (kbytes, -d) unlimited
scheduling priority             (-e) 0
file size               (blocks, -f) unlimited
pending signals                 (-i) 58729
max locked memory       (kbytes, -l) 64
max memory size         (kbytes, -m) unlimited
open files                      (-n) 32000
pipe size            (512 bytes, -p) 8
POSIX message queues     (bytes, -q) 819200
real-time priority              (-r) 0
stack size              (kbytes, -s) 10240
cpu time               (seconds, -t) unlimited
max user processes              (-u) 58729
virtual memory          (kbytes, -v) unlimited
file locks                      (-x) unlimited