拉取镜像

docker pull 镜像名称

$ docker images
REPOSITORY    TAG       IMAGE ID       CREATED        SIZE
test/ubuntu   v1        05443cf468db   3 hours ago    0B
ubuntu        latest    e34e831650c1   2 weeks ago    77.9MB
hello-world   latest    d2c94e258dcb   9 months ago   13.3kB
$ docker pull ubuntu:20.04 # 拉取ubuntu:20.04镜像
20.04: Pulling from library/ubuntu
527f5363b98e: Pull complete
Digest: sha256:f2034e7195f61334e6caff6ecf2e965f92d11e888309065da85ff50c617732b8
Status: Downloaded newer image for ubuntu:20.04
docker.io/library/ubuntu:20.04
$ docker images
REPOSITORY    TAG       IMAGE ID       CREATED        SIZE
test/ubuntu   v1        05443cf468db   3 hours ago    0B
ubuntu        latest    e34e831650c1   2 weeks ago    77.9MB
ubuntu        20.04     f78909c2b360   6 weeks ago    72.8MB
hello-world   latest    d2c94e258dcb   9 months ago   13.3kB