Change Docker Root Dir Path in Linux

docker-change-root-dir.sh

#!/bin/bash

CURRENTDOCKERROOTDIR=/var/lib/docker
NEWDOCKERROOTDIR=
COPYFOLDER=false
DONTSTARTDOCKERAFTERCHANGE=false
FORCEOVERWRITE=false
JSONDAEMONFILEPATH=/etc/docker/daemon.json
STORAGEDRIVER=

usage="$(basename "$0") -o path [-h] [-i /current/root/dir] [-p /path/to/json/daemonfile] [-S storage-driver for docker] [-c] [-n] [-f]

where:
    -o New Docker Root Dir path
    -h show this help text
    -i Current docker root dir (default: $CURRENTDOCKERROOTDIR)
    -p Path to json daemon file (default: $JSONDAEMONFILEPATH)
    -S Docker storage driver to use (default: none)
    -c Copy old docker folder to new path and set permissions (default: false)
    -n Don't Start docker after script ends (default: false)
    -f Force overwrite daemon file (default: false)"

while getopts "i:o:p:S:cnfh" opt; do
  case $opt in
    i) CURRENTDOCKERROOTDIR="$OPTARG"
    ;;
    o) NEWDOCKERROOTDIR="$OPTARG"
    ;;
    c) COPYFOLDER=true
    ;;
    n) DONTSTARTDOCKERAFTERCHANGE=true
    ;;
    f) FORCEOVERWRITE=true
    ;;
    p) JSONDAEMONFILEPATH="$OPTARG"
    ;;
    S) STORAGEDRIVER="$OPTARG"
    ;;
    h) echo "$usage"
       exit
       ;;
    \?) echo "Invalid option -$OPTARG" >&2
        echo "$usage" >&2
        exit 1
    ;;
  esac
  
  case $opt in
    i|o|p|S)
          case $OPTARG in
            -*) echo "Option $opt needs a valid argument"
            echo "$usage" >&2
            exit 1
            ;;
        esac
    ;;
  esac
done

if [ -z "$NEWDOCKERROOTDIR" ]; then
    echo "No new dir supplied supplied. Check usage with script.sh -h"
    echo "$usage" >&2
    exit 1
fi

DOCKERFOLDER="$NEWDOCKERROOTDIR/docker"

if [ $(/usr/bin/id -u) -ne 0 ]; then
    echo "Not running as root"
    exit 1
fi

if [[ -f "$JSONDAEMONFILEPATH" && "$FORCEOVERWRITE" = false ]]; then
    echo "$JSONDAEMONFILEPATH already exists. Please delete it first, or manually add the root path. Pass -f to force overwrite."
    exit 1
else 
    echo "$JSONDAEMONFILEPATH already exists but -f flag is true. Will Overwrite. Old Contents are printed below."
    echo "=========================================================="
    echo "$(<$JSONDAEMONFILEPATH)"
    echo "=========================================================="
fi

systemctl stop docker
systemctl stop docker.socket

if [ "$COPYFOLDER" = true ]; then
    mkdir -p "$NEWDOCKERROOTDIR"
    chown -R root:root $NEWDOCKERROOTDIR
    mkdir "$DOCKERFOLDER"
    rsync -a "$CURRENTDOCKERROOTDIR" "$DOCKERFOLDER/"
fi;

if [ -z "$STORAGEDRIVER" ]; then
    echo "{\"data-root\": \"$DOCKERFOLDER\"}" > "$JSONDAEMONFILEPATH"
else
    echo "{\"data-root\": \"$DOCKERFOLDER\",\"storage-driver\": \"$STORAGEDRIVER\"}" > "$JSONDAEMONFILEPATH"
fi;

if [ "$DONTSTARTDOCKERAFTERCHANGE" = false ]; then
    systemctl daemon-reload
    systemctl start docker
    systemctl start docker.socket
    systemctl is-active --quiet docker && SUCCESS=true || SUCCESS=false

    if [ "$SUCCESS" = true ]; then
        echo "=========================================================="
        echo "Successfully updated (maybe). Check below"
        echo "=========================================================="
        docker info | grep 'Docker Root Dir'
        exit 0;
    fi;
    echo "Error starting docker. Check status below."
    systemctl status docker --no-pager
fi;
echo ""
echo "Done! If there's any issues with docker starting, delete (or replace with contents printed above) $JSONDAEMONFILEPATH file."
echo "Running \"dockerd\" command might help"