CentOS 7.X 中Docker搭建本地仓库registry 以及报错解决

去docker hub下载镜像比较慢，而且自己内部的镜像一般要求对速度和安全性要求较高，于是就可以考虑搭建本地仓库registry来实现，下边简单介绍下步骤。
环境：centos 7.2
1，安装docker
yum install docker -y
systemctl start docker.service
systemctl enable docker.service

2,搭建仓库
下载registry
docker search registry

[root@docker5 registry]# docker search registry
INDEX       NAME                                                DESCRIPTION                                     STARS     OFFICIAL   AUTOMATED
docker.io   docker.io/registry                                  Containerized docker registry                   894       [OK]      
docker.io   docker.io/konradkleine/docker-registry-frontend     Browse and modify your Docker registry in ...   99                   [OK]
docker.io   docker.io/atcol/docker-registry-ui                  A web UI for easy private/local Docker Reg...   79                   [OK]
docker.io   docker.io/distribution/registry                     WARNING: NOT the registry official image!!...   38                   [OK]
docker.io   docker.io/samalba/docker-registry                                                                   36                   [OK]
docker.io   docker.io/hyper/docker-registry-web                 Web UI for private docker registry v2.          28                   [OK]
docker.io   docker.io/marvambass/nginx-registry-proxy           Docker Registry Reverse Proxy with Basic A...   27                   [OK]
docker.io   docker.io/h3nrik/registry-ldap-auth                 LDAP and Active Directory authentication p...   12                   [OK]
docker.io   docker.io/jhipster/jhipster-registry                JHipster Registry, based on Netflix Eureka...   6                    [OK]
[root@docker5 registry]# docker pull docker.io/registry
等待下载完成。
搭建仓库：

docker run -d -p 5000:5000 -v /home/registry:/tmp/registry registry
默认情况下docker会将仓库存放于容器的 /tmp/registry 目录下，可以通过 -v 参数来将镜像文件保存到我们指定的路径。
查看是否运行：

[root@docker5 registry]# netstat  -tunlp | grep  5000
tcp6       0      0 :::5000                 :::*                    LISTEN      3791/docker-proxy  
更改一个标签：

docker tag  mysql:latest 192.168.2.75:5000/mysql20160615
上传测试镜像到本地仓库：

docker push 192.168.2.75:5000/mysql20160615
这里如果是已经创建了https可以操作成功过，如果是http会报错。原因是Docker从1.3.X之后默认docker registry使用的是https，所以当用docker pull命令下载远程镜像时，如果远程docker registry是非https的时候就会报上面的错误。解决办法：
vi /etc/sysconfig/docker

OPTIONS='--selinux-enabled --insecure-registry 192.168.2.75:5000' 其中--insecure-registry 192.168.2.75:5000是自己添加的。
设置以后重启docker和对应容器，重新push一下，成功。

[root@docker5 registry]# docker push 192.168.2.75:5000/testimage
The push refers to a repository [192.168.2.75:5000/testimage] (len: 1)
Sending image list
Pushing repository 192.168.2.75:5000/testimage (1 tags)
3690474eb5b4: Image successfully pushed
b48a20c39b28: Image successfully pushed
c79ebe41b35a: Image successfully pushed
2a332da70fd1: Image successfully pushed
Pushing tag for rev [2a332da70fd1] on {http://192.168.2.75:5000/v1/repositories/testimage/tags/latest}
本地仓库以及url查看状态：

[root@docker5 registry]# ll
total 4
drwxr-xr-x. 6 root root 4096 Jun 22 14:27 images
drwxr-xr-x. 3 root root   20 Jun 22 14:27 repositories
[root@docker5 registry]# du -sh  ./*
68M ./images
16K ./repositories
[root@docker5 registry]# curl  http://192.168.2.75:5000/v1/search
{"num_results": 1, "query": "", "results": [{"description": "", "name": "library/testimage"}]}[root@docker5 registry]#
本地仓库镜像下载测试验证：
进入另外一台内网机器进行镜像下载测试，比如我的另外一台测试机：192.168.2.76，操作如下：
首先进入修改docker配置文件并重启

OPTIONS='--selinux-enabled --insecure-registry 192.168.2.75:5000' 其中--insecure-registry 192.168.2.75:5000是自己添加的本地仓库地址。
pull过程如下：

[root@docker6 ~]# systemctl  restart docker
[root@docker6 ~]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             VIRTUAL SIZE
[root@docker6 ~]# docker pull  192.168.2.75:5000/testimage
Using default tag: latest
2a332da70fd1: Download complete
3690474eb5b4: Download complete
b48a20c39b28: Download complete
c79ebe41b35a: Download complete
Status: Downloaded newer image for 192.168.2.75:5000/testimage:latest
192.168.2.75:5000/testimage: this image was pulled from a legacy registry.  Important: This registry version will not be supported in future versions of docker.
 
[root@docker6 ~]# docker images
REPOSITORY                    TAG                 IMAGE ID            CREATED             VIRTUAL SIZE
192.168.2.75:5000/testimage   latest              2a332da70fd1        2 weeks ago         196.7 MB
 没有问题，本地仓库搭建成功。