+ docker pull alpine:3.9 3.9: Pulling from library/alpine 31603596830f: Pulling fs layer 31603596830f: Verifying Checksum 31603596830f: Download complete 31603596830f: Pull complete Digest: sha256:414e0518bb9228d35e4cd5165567fb91d26c6a214e9c95899e1e056fcd349011 Status: Downloaded newer image for alpine:3.9 docker.io/library/alpine:3.9