[root@MyCentos7 var]# docker pull javaUsing default tag: latestTrying to pull repository docker.io/library/java ... latest: Pulling from docker.io/lib ...
[root@MyCentos7 var]# docker pull java
Using default tag: latest
Trying to pull repository docker.io/library/java ...
latest: Pulling from docker.io/library/java
5040bd298390: Pulling fs layer
fce5728aad85: Pulling fs layer
76610ec20bf5: Waiting
60170fec2151: Waiting
e98f73de8f0d: Waiting
11f7af24ed9c: Waiting
49e2d6393f32: Waiting
bb9cdec9c7f3: Waiting
error pulling image configuration: Get https://dseasb33srnrn.cloudfront.net/registry-v2/docker/registry/v2/blobs/sha256/d2/d23bdf5b1b1b1afce5f1d0fd33e7ed8afbc084b594b9ccf742a5b27080d8a4a8/data?Expires=1526065549&Signature=PK~0RcvGATZkFC7pw6dXSxzQ6Tj5n9tzwNZAC-56SV~hNhrxNu1SQfJQB4snQuy~iojnVCQF1jI063OGHccx7IrRrKgqiczJVltKpORMdKjPplx-WwJCc39lUpNA~0gkHbqCpCPD67HyGp1G688KxHJo5QPEvwC7W5Lai-sw3Ro_&Key-Pair-Id=APKAJECH5M7VWIS5YZ6Q: net/http: TLS handshake timeout
出現這個問題原因為國內網路問題，無法連接到 docker hub。 但國內有 daocloud加速，docker指定該源即可。
centos7處理辦法如下，添加後重啟docker ：
[root@MyCentos7 var]# vim /etc/sysconfig/docker
紅色字體為添加內容
# /etc/sysconfig/docker
# Modify these options if you want to change the way the docker daemon runs
OPTIONS='--selinux-enabled --log-driver=journald --signature-verification=false --registry-mirror=http://f2d6cb40.m.daocloud.io'
if [ -z "${DOCKER_CERT_PATH}" ]; then
DOCKER_CERT_PATH=/etc/docker
fi
# Do not add registries in this file anymore. Use /etc/containers/registries.conf
# from the atomic-registries package.
#
# On an SELinux system, if you remove the --selinux-enabled option, you
# also need to turn on the docker_transition_unconfined boolean.
# setsebool -P docker_transition_unconfined 1
# Location used for temporary files, such as those created by
# docker load and build operations. Default is /var/lib/docker/tmp
# Can be overriden by setting the following environment variable.
# DOCKER_TMPDIR=/var/tmp
# Controls the /etc/cron.daily/docker-logrotate cron job status.
# To disable, uncomment the line below.
# LOGROTATE=false
# docker-latest daemon can be used by starting the docker-latest unitfile.
# To use docker-latest client, uncomment below lines
#DOCKERBINARY=/usr/bin/docker-latest
#DOCKERDBINARY=/usr/bin/dockerd-latest
#DOCKER_CONTAINERD_BINARY=/usr/bin/docker-containerd-latest
#DOCKER_CONTAINERD_SHIM_BINARY=/usr/bin/docker-containerd-shim-latest
[root@MyCentos7 var]# service docker restart
[root@MyCentos7 var]# docker pull java
Using default tag: latest
Trying to pull repository docker.io/library/java ...
latest: Pulling from docker.io/library/java
5040bd298390: Pull complete
fce5728aad85: Pull complete
76610ec20bf5: Pull complete
60170fec2151: Pull complete
e98f73de8f0d: Pull complete
11f7af24ed9c: Pull complete
49e2d6393f32: Pull complete
bb9cdec9c7f3: Pull complete
Digest: sha256:5d6cc05636c16abb3e49f2117fd6aa4bddb8f0d775075972a8b9b03f754ea9f2
Status: Downloaded newer image for docker.io/java:latest
成功
