docker-daemon-log-opts.sh

#!/bin/sh

# create docker engine config at /etc/docker/daemon.json
# to limit the size of container logs.
# usage (with curl):
# curl -s https://gist.githubusercontent.com/wzulfikar/e7740906110beaa90216f8f37320f5d8/raw/docker-daemon-log-opts.sh | sh

config_dir="/etc/docker"
config_file="$config_dir/daemon.json"
max_size=50m

IFS=''
config='{
  "log-opts": {
    "max-size": "'$max_size'",
    "max-file": "1"
  }
}'

echo "creating config at ${config_file}.."

if [ -f "$config_file" ]; then
  echo "[ABORTED] docker daemon config already exists."
  echo ""
  echo "you can manually add below 'log-opts' to your '$config_file':"
  echo "$config"
  exit
fi

if [ ! -d "$config_dir" ]; then
  echo "[ERROR] cannot find config dir at '$config_dir'."
  echo ""
  echo "are you sure that docker is running in this host?"
  exit
fi

# check if user has write permission
if [ ! -w "$config_dir" ]; then
  echo "[ERROR] config dir is not writeable."
  echo ""
  echo "please make sure that you've write permission at '$config_dir'."
  exit
fi

# write config to config file
echo $config > $config_file

echo "[DONE] finished writing docker daemon config for log-opts."
echo "size of container logs will be limited to $max_size."
echo ""
echo "you'll need to restart docker service to load the config."
echo 'ie. `service docker restart` (for ubuntu)'