Python Error "ImportError: No module named pkg_resources"

I encountered the ImportError today while trying to use pip. Somehow the setup tools package had been deleted in my Python environment.

=============== File "/usr/bin/gunicorn", line 5, in <module> from pkg_resources import load_entry_point ImportError: No module named pkg_resources ===============

Fix to reset to python Environment curl https://bootstrap.pypa.io/ez_setup.py | python

Private Docker Registry @ Centos7

Here we will try to create a private docker registry for the internal use with security.

Install the Packages
>> yum update -y ;
>> yum install http://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-5.noarch.rpm
>> yum install docker-registry

The configruetion file will be at /etc/docker-registry.yml

Edit the dev section to match the needed Storage portion

 # This is the default configuration when no flavor is specified
dev:
    storage: local
    storage_path: /home/registry
    loglevel: debug

Create the Directory at /home/registry or Configure the storage there.

Start and enable the Docker Registry

>>systemctl start docker-registry
>>systemctl status docker-registry
docker-registry.service - Registry server for Docker
   Loaded: loaded (/usr/lib/systemd/system/docker-registry.service; enabled)
   Active: active (running) since Mon 2014-12-15 21:20:26 UTC; 5s ago
 Main PID: 19468 (gunicorn)
   CGroup: /system.slice/docker-registry.service
           ├─19468 /usr/bin/python /usr/bin/gunicorn --access-logfile - --debug --max-requests 100 --gracefu...
           ├─19473 /usr/bin/python /usr/bin/gunicorn --access-logfile - --debug --max-requests 100 --gracefu...
           ├─19474 /usr/bin/python /usr/bin/gunicorn --access-logfile - --debug --max-requests 100 --gracefu...
           ├─19475 /usr/bin/python /usr/bin/gunicorn --access-logfile - --debug --max-requests 100 --gracefu...
           ├─19482 /usr/bin/python /usr/bin/gunicorn --access-logfile - --debug --max-requests 100 --gracefu...
           ├─19488 /usr/bin/python /usr/bin/gunicorn --access-logfile - --debug --max-requests 100 --gracefu...
           ├─19489 /usr/bin/python /usr/bin/gunicorn --access-logfile - --debug --max-requests 100 --gracefu...
           ├─19494 /usr/bin/python /usr/bin/gunicorn --access-logfile - --debug --max-requests 100 --gracefu...
           └─19496 /usr/bin/python /usr/bin/gunicorn --access-logfile - --debug --max-requests 100 --gracefu...

Dec 15 21:20:26 docker-registry.novalocal gunicorn[19468]: 2014-12-15 21:20:26 [19468] [INFO] Listening a...68)
Dec 15 21:20:26 docker-registry.novalocal gunicorn[19468]: 2014-12-15 21:20:26 [19468] [INFO] Using worke...ent
Dec 15 21:20:26 docker-registry.novalocal gunicorn[19468]: 2014-12-15 21:20:26 [19473] [INFO] Booting wor...473
Dec 15 21:20:26 docker-registry.novalocal gunicorn[19468]: 2014-12-15 21:20:26 [19474] [INFO] Booting wor...474
Dec 15 21:20:26 docker-registry.novalocal gunicorn[19468]: 2014-12-15 21:20:26 [19475] [INFO] Booting wor...475
Dec 15 21:20:26 docker-registry.novalocal gunicorn[19468]: 2014-12-15 21:20:26 [19482] [INFO] Booting wor...482
Dec 15 21:20:27 docker-registry.novalocal gunicorn[19468]: 2014-12-15 21:20:27 [19488] [INFO] Booting wor...488
Dec 15 21:20:27 docker-registry.novalocal gunicorn[19468]: 2014-12-15 21:20:27 [19489] [INFO] Booting wor...489
Dec 15 21:20:27 docker-registry.novalocal gunicorn[19468]: 2014-12-15 21:20:27 [19494] [INFO] Booting wor...494
Dec 15 21:20:27 docker-registry.novalocal gunicorn[19468]: 2014-12-15 21:20:27 [19496] [INFO] Booting wor...496
Hint: Some lines were ellipsized, use -l to show in full.


Check whether its working
>>curl localhost:5000
"docker-registry server (local) (v0.6.8)"
[root@docker-registry ~]#

Now we need to add authentication to the registry and an self signed certificate SSL

Creating the Certificates
# Generate private key
>>openssl genrsa -out docker-registry.key 2048

# Generate CSR **** MAKE SURE WE GIVE THE SERVER NAME CORRECTLY***
>>openssl req -new -key docker-registry.key -out docker-registry.csr

# Generate Self Signed Key
>>openssl x509 -req -days 365 -in docker-registry.csr -signkey docker-registry.key -out docker-registry.crt

# Copy the files to the correct locations
>>cp docker-registry.crt /etc/pki/tls/certs
>>cp docker-registry.key /etc/pki/tls/private/docker-registry.key
>>cp docker-registry.csr /etc/pki/tls/private/docker-registry.csr

#Update the CA-Certificate in the Centos7
>>update-ca-trust enable
>>cp docker-registry.crt /etc/pki/ca-trust/source/anchors/
>>update-ca-trust extract


>>yum install nginx httpd-tools

Create a User for authentication
>>sudo htpasswd -c /etc/nginx/docker-registry.htpasswd dockeruser
<Password will be prompted>

Configure nginx Virtual Host (/etc/nginx/conf.d/virtualhost.conf).

============
# For versions of Nginx > 1.3.9 that include chunked transfer encoding support
# Replace with appropriate values where necessary

upstream docker-registry {
 server localhost:5000;
}

server {
 listen 8080;
 server_name docker.registry;

 # ssl on;
 # ssl_certificate /etc/pki/tls/certs/docker-registry.crt;
 # ssl_certificate_key /etc/pki/tls/private/docker-registry.key;

 proxy_set_header Host       $http_host;   # required for Docker client sake
 proxy_set_header X-Real-IP  $remote_addr; # pass on real client IP

 client_max_body_size 0; # disable any limits to avoid HTTP 413 for large image uploads

 # required to avoid HTTP 411: see Issue #1486 (https://github.com/dotcloud/docker/issues/1486)
 chunked_transfer_encoding on;

 location / {
     # let Nginx know about our auth file
     auth_basic              "Restricted";
     auth_basic_user_file    docker-registry.htpasswd;

     proxy_pass http://docker-registry;
 }
 location /_ping {
     auth_basic off;
     proxy_pass http://docker-registry;
 }
 location /v1/_ping {
     auth_basic off;
     proxy_pass http://docker-registry;
 }

}
============
Restart the Service
>>>systemctl restart nginx

Checking the Resgistry curl https://<username>:<password>@<hostname>:<port>  ******Hostanme should be the one we gave in the certificate ********

>> curl https://dockeruser:docker@docker-registry:8080
"docker-registry server (local) (v0.6.8)"
[root@docker-registry ~]#


Configure CoreOs to use the Private Docker Registry

To use the Private Registry in the coreos we need to Copy the CA certificate from the registry server to the Coreos Docker server.

Copy the CA certificate to /etc/ssl/certs/docker-registry.pem as pem .
now update the Certificate list using command
>>sudo update-ca-certificates

Also in this case as our server name is docker-registry:8080 we need to copy the CA certificate to /etc/docker/cert.d/docker-registry\:8080/ca.crt also.

And restart the docker service

Now try to login to registry

core@coreos ~ $ docker login https://docker-registry:8080
Username :
Password :
Email :
Login Succeeded
core@coreos ~ $


Now to Push the Image to Private repo we need to tag the image in format <registry-hostname>:<port>

Import/Export a Docker Images

For Exporting a docker image from one server to another we can user private registry or we can also tar the image and copy the tar over to new server and import it into the new server using the tar file.

Export a Docker image to a file.

docker save image > image.tar

Import a Docker image

docker load -i (archivefile)
Loads in a Docker image in the following formats: .tar, .tar.gz, .tar.xz. lrz is not supported.