$ systemctl status docker

# 미설치
* docker.service
   Loaded: not-found (Reason: No such file or directory)
   Active: inactive (dead)

# 설치
* docker.service - Docker Application Container Engine
   Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
   Active: active (running)

# 버전확인
$ docker -v
Docker version 20.10.7, build f0df350

# 설치된 버전을 삭제할 경우
$ sudo apt-get remove docker docker-engine docker.io

# 필수 패키지 설치
$ sudo apt-get install apt-transport-https ca-certificates curl gnupg-agent software-properties-common

# GPG Key 인증
$ url -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
OK

# docker Repository 등록
$ sudo add-apt-repository \
 "deb [arch=amd64] https://download.docker.com/linux/ubuntu \
 $(lsb_release -cs) \
 stable"

# Docker Install
$ sudo apt-get update && sudo apt-get install docker-ce
## 아래와 같은 로그가 나와야 정상처리
Get:1 http://security.ubuntu.com/ubuntu xenial-security InRelease [109 kB]                
Hit:2 http://kr.archive.ubuntu.com/ubuntu xenial InRelease                                
Get:3 http://kr.archive.ubuntu.com/ubuntu xenial-updates InRelease [109 kB]        
Get:4 http://kr.archive.ubuntu.com/ubuntu xenial-backports InRelease [107 kB]
Get:5 http://kr.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages [2049 kB]
Get:6 http://kr.archive.ubuntu.com/ubuntu xenial-updates/main i386 Packages [1525 kB]
Fetched 3899 kB in 4s (974 kB/s)                         
Reading package lists... Done


# User가 Docker 사용할 수 있도록 설정
$ sudo usermod -aG docker $USER

# 설치 (아래 한줄...)
$ sudo curl -L https://github.com/docker/compose/releases/download/1.25.0-rc2/docker-compose-`uname -s`-`uname -m` -o /usr/local/bin/docker-compose

# 권한설정
$ sudo chmod +x /usr/local/bin/docker-compose

# 버전 확인
$ docker-compose --version
docker-compose version 1.25.0-rc2, build 661ac20e

$ sudo service docker start

# compose 실행
$ sudo docker-compose up -d # -d : 백그라운드 실행

# compose 종료
$ sudo docker-compose down