Can not pull/push images after update docker to 1.12
<p>The private registry was worked well based on docker 1.10.3,but I can not pull/push images after the docker updated to 1.12.0.</p>

<p>I had modified the /etc/sysconfig/docker as:</p>

<pre><code>OPTIONS='--selinux-enabled=true --insecure-registry=myip:5000'
</code></pre>

<p>or</p>

<pre><code>OPTIONS='--selinux-enabled=true --insecure-registry myip:5000'
</code></pre>

<p>but when I exec pull/push,I got this error:</p>

<pre><code>$ docker pull myip:5000/cadvisor
Using default tag: latest
Error response from daemon: Get https://myip:5000/v1/_ping: http: server gave HTTP response to HTTPS client
</code></pre>

<p>when I change back docker to 1.10.3, it still work well as below:</p>

<pre><code>$ docker pull myip:5000/cadvisor
Using default tag: latest
Trying to pull repository myip:5000/cadvisor ... 
latest: Pulling from myip:5000/cadvisor
09d0220f4043: Pull complete 
a3ed95caeb02: Pull complete 
151807d34af9: Pull complete 
14cd28dce332: Pull complete     
Digest:
sha256:33b6475cd5b7646b3748097af1224de3eee3ba7cf5105524d95c0cf135f59b47
Status: Downloaded newer image for myip/cadvisor:latest
</code></pre>

<p>Some relative information are listed below:</p>

<pre><code>docker version
Client:
Version: 1.12.0
API version: 1.24
Go version: go1.6.3
Git commit: 8eab29e
Built:

OS/Arch: linux/amd64

Server:
Version: 1.12.0
API version: 1.24
Go version: go1.6.3
Git commit: 8eab29e
Built:

OS/Arch: linux/amd64

docker info
Containers: 4
Running: 1
Paused: 0
Stopped: 3
Images: 241
Server Version: 1.12.0
Storage Driver: devicemapper
Pool Name: docker-253:0-6809-pool
Pool Blocksize: 65.54 kB
Base Device Size: 107.4 GB
Backing Filesystem: xfs
Data file: /dev/loop0
Metadata file: /dev/loop1
Data Space Used: 5.459 GB
Data Space Total: 107.4 GB
Data Space Available: 34.74 GB
Metadata Space Used: 9.912 MB
Metadata Space Total: 2.147 GB
Metadata Space Available: 2.138 GB
Thin Pool Minimum Free Space: 10.74 GB
Udev Sync Supported: true
Deferred Removal Enabled: false
Deferred Deletion Enabled: false
Deferred Deleted Device Count: 0
Data loop file: /var/lib/docker/devicemapper/devicemapper/data
WARNING: Usage of loopback devices is strongly discouraged for production use. Use '--storage-opt dm.thinpooldev' to specify a custom block storage device.
Metadata loop file: /var/lib/docker/devicemapper/devicemapper/metadata
Library Version: 1.02.107-RHEL7 (2016-06-09)
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: host overlay null bridge
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Security Options: seccomp
Kernel Version: 3.10.0-229.el7.x86_64
Operating System: CentOS Linux 7 (Core)
OSType: linux
Architecture: x86_64
CPUs: 24
Total Memory: 62.39 GiB
Name: server_3
ID: TITS:BL4B:M5FE:CIRO:5SW6:TVIV:HW36:J7OS:WLHF:46T6:2RBA:WCNV
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): true
File Descriptors: 21
Goroutines: 32
System Time: 2016-08-02T10:33:06.414048675+08:00
EventsListeners: 0
Registry: https://index.docker.io/v1/
WARNING: bridge-nf-call-iptables is disabled
WARNING: bridge-nf-call-ip6tables is disabled
Insecure Registries:
127.0.0.0/8

docker exec &lt;registry-container&gt; registry -version
registry github.com/docker/distribution v2.2.1
</code></pre>

<p>After I restart the docker daemon in debug mode, the daemon logs when reproducing my problem are listed below:</p>

<pre><code>DEBU[0794] Calling POST /v1.24/images/create?fromImage=10.10.10.40%3A5000%2Fcadvisor&amp;tag=latest 
DEBU[0794] hostDir: /etc/docker/certs.d/10.10.10.40:5000 
DEBU[0794] hostDir: /etc/docker/certs.d/10.10.10.40:5000 
DEBU[0794] Trying to pull 10.10.10.40:5000/cadvisor from https://10.10.10.40:5000 v2 
WARN[0794] Error getting v2 registry: Get https://10.10.10.40:5000/v2/: http: server gave HTTP response to HTTPS client 
ERRO[0794] Attempting next endpoint for pull after error: Get https://10.10.10.40:5000/v2/: http: server gave HTTP response to HTTPS client
DEBU[0794] Trying to pull 10.10.10.40:5000/cadvisor from https://10.10.10.40:5000 v1 
DEBU[0794] hostDir: /etc/docker/certs.d/10.10.10.40:5000
DEBU[0794] attempting v1 ping for registry endpoint https://10.10.10.40:5000/v1/
DEBU[0794] Fallback from error: Get https://10.10.10.40:5000/v1/_ping: http: server gave HTTP response to HTTPS client 
ERRO[0794] Attempting next endpoint for pull after error: Get https://10.10.10.40:5000/v1/_ping: http: server gave HTTP response to HTTPS client
ERRO[0794] Handler for POST /v1.24/images/create returned error: Get https://10.10.10.40:5000/v1/_ping: http: server gave HTTP response to HTTPS client 
DEBU[1201] clean 2 unused exec commands
</code></pre>

<p>What's more, I just run a simple command to launch the private registry for test, anything else is by default:</p>

<pre><code>docker run -d -p 5000:5000 --restart=always --name registry -v 'pwd'/data:/var/lib/registry registry:2
</code></pre>

<p>No proxy is configured. In summary, it is only a quiet sample environment for test.</p>