fix(guide): simplify directory structure

guide/english/containers/docker/basic-commands-of-docker/index.md

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+# Useful commands for Docker
+- Docker is mainly used for run programs on server side.
+- Companies customize their OS before use. They don't require many things like GUI.
+-  Less program means less RAM used and more security.
+	- More features means more chances to hack, more vulnerabilities.
+- We use OS to run program. Docker gives us an environment to run our program. 
+
+## Installing docker-engine
+### For  Redhat OS
+- First, setup yum repo
+	```
+	[docker]
+	baseurl = https://yum.dockerproject.org/repo/main/centos/7
+	gpgcheck=0 
+	```
+- Then, install **docker-engine**
+`$ yum install docker-engine`
+ 
+ ###  Start the services of docker
+ `$ systemctl restart docker`
+ It starts the docker server.
+ 
+### See all the images available in docker
+`$ docker images`
+The default _docker images_ will show all top level images, their repository and tags, and their size.
+
+### Load an image in docker
+`$ docker load -i ubuntu-14.04.tar`
+- **i** - Read from tar archive file, instead of STDIN
+
+It loads an image or repository from a tar archive (even if compressed with gzip, bzip2, or xz) from a file or STDIN. It restores both images and tags.
+
+### Docker run reference
+- Docker runs processes in isolated containers.
+- A container is a process which runs on a host. The host may be local or remote. 
+- When an operator executes `docker run`, the container process that runs is isolated in that it has its own file system, its own networking, and its own isolated process tree separate from the host.
+
+### Run or start a new OS
+`$ docker run -it ubuntu:14.04`
+- The `docker run` command first `creates` a writeable container layer over the specified image, and then `starts` it using the specified command.
+- The above example runs a container using the `ubuntu:14.04` image. The `-it` instructs Docker to allocate a pseudo-TTY connected to the container’s stdin; creating an interactive `bash` shell in the container.
+
+### See all the running OSs
+`$ docker ps`
+- The  `docker ps`  command only shows running containers by default.
+- To see all containers, use the  `-a`  (or  `--all`) flag:
+
+`$ docker ps -a`
+
+### Come out from docker OS console
+`exit`
+
+### From shell of docker OS, for coming out without exiting container
+press _ctrl + p + q_
+
+### From terminal of base system, to run a command in docker OS
+`$ docker exec mycontainer ifconfig`
+- **mycontainer** is the name of container.
+- The `docker exec` command runs a new command in a running container.
+
+
+### Usually run docker using this command
+`$ docker run –dit ubuntu:14.04`
+- **i** - interactive
+- **t** - terminal
+- **d** - detach
+
+### Stop all running OSs
+```
+$ docker ps -q //shows id of every running OS 
+$ docker stop  $(docker ps -q) 
+```
+
+### Permanently remove a container
+`$ docker rm id`
+
+### Permanently Remove all the stopped containers
+`$ docker rm $(docker ps -a -q)`
+- This command will delete all stopped containers.
+- The command `docker ps -a -q` will return all existing container IDs and pass them to the `rm` command which will delete them. 
+- Any running containers will not be deleted.
+
+### Remove containers while running (forcefully)
+`$ docker rm -f $(docker ps -a -q)`
+
+### Giving docker OS a name when starting
+- By default, docker gives unique name to every container with a unique id.
+- We can also give a name to container using following command -
+`$ docker run -it --name adarsh centos:latest`
+
+### Copy a file in container
+`$ docker cp /root/form.txt  myconatiner:/`
+This command will copy a file form.txt from the base system to the specified container.
+ 
+### Download docker images
+[docker hub](http://hub.docker.com) - All the available docker images can be downloaded from this URL.
+
+### Check different versions of OS that are available
+```
+$ docker search ubuntu //search
+$ docker pull ubuntu:17.10 //downlaod required version 
+```
+
+## Docker Storage
+
+### Basic Storage types 
+1.	**Empheral disk (temporary)** – OS removal will remove data (like windows C drive)
+2.	**Persistent disk (permanent)** -  OS removal will not erase data (like windows D drive)
+    - **-v** gives persistent storage. OS removal will not remove data.
+
+### Docker volume manager
+Docker by default takes space from **/** drive of host system to store data. Overall **/** drive amount of storage docker can use.
+
+### Give separate space to a docker container
+- Make a partition, format it and mount in base system. 
+Let the partition created is **mypart**
+- Then, run following command
+`$ docker run –it -v /mypart:/data centos`
+  - **mypart** is a partition in base system and **data** is the folder where docker will store it's data.
+  - **v** - volume
+
+### Attaching dvd to a container
+`$ docker run –it –v /run/media/root/RHEL-7.3\ Server.. centos`
+This command will attach a RHEL to the container.
+
+### Copy content from a folder of base system to _/data_ in docker centos
+`$ docker run –it -v /folder_name:/data centos`

guide/english/containers/docker/creating-a-new-container/index.md

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+---
+title: Creating a new container
+---
+
+Creating a container using Docker CLI
+
+```yaml
+docker create [OPTIONS] IMAGE [COMMAND] [ARG...]
+```
+# Examples
+Create and start a container
+```sh
+$ docker create -t -i fedora bash
+```

guide/english/containers/docker/creating-webserver-image-of-docker/index.md

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+# Running Web Server inside Docker
+### Start docker and it’s container - 
+	```
+	$ systemctl restart docker 
+	$ systemctl enable docker 
+	$ docker run -it --name webserver centos:latest
+	```
+
+### Install httpd
+- **yum** is already configured in centos docker image.
+So directly install **httpd** software - 
+`$ yum install httpd -y`
+
+- Create a dummy web page to check the server -  
+	```
+	$ cd /var/www/html 
+	$ vi index.html
+	```
+
+### Start services - 
+  - If we use **systemctl** to start the services, this will not work and gives an error.
+  - **systemctl** doesn't work in docker.
+  - In actual RedHat system, when we start a service it actually runs a script in background. That script start daemons.
+  - To find the path of that script, check status of service  
+`$ systemctl status httpd`
+`Loaded` option shows script file path.
+  - In that file, we have a line which actually starts service - 
+`ExecStart = /usr/sbin/httpd....... `
+So the command `/usr/sbin/httpd` actually starts **httpd** server.
+
+- Service is running or not, can be checked by - 
+`$ ps -aux | grep httpd`
+ 
+- So we don't require `systemctl` we can directly start our web server using- 
+`$ /usr/sbin/httpd`
+This will start the web server.
+
+- `ifconfig` doesn't work in docker. 
+  - So install software, which gives `ifconfig` command.
+  - It can be checked in actual Redhat system by running this command- 
+  `$ rpm -qf /usr/sbin/ifconfig`
+  - This comes from **net-tools** package.
+  - So Install **net-tools** in docker os.
+
+- Making _image_ of created web server - 
+`$ docker commit webserver apacheimg:v1`
+  - Name of container is _webserver_.
+  - This image can be share with exact setup with other users.
+
+- To save created image - 
+`$ docker save apacheimg:v1 -o mywebserver.tar`
+
+- To start **httpd** service automatically when container starts -
+  - Write `/usr/sbin/httpd` in following file. 
+	`$ vim /root/.bashrc`
+
+- To copy a file in container from the base system - 
+`$ docker cp /root/form.txt  myconatiner:/`
+
+## Summary
+Summary of all the commands -
+```
+$ docker run -it --name webserver centos:latest
+$ yum install httpd -y
+$ rpm -q httpd
+$ cd /var/www/html
+$ vi index.html
+// write some web content
+
+$ /usr/sbin/httpd
+$ yum install net-tool
+
+$ ifconfig
+```

guide/english/containers/docker/index.md

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+---
+title: Docker
+---
+## Docker
+
+[Docker](https://www.docker.com/) is a widely-used container platform available for Linux, Windows, and Mac, as well as cloud providers like AWS and Azure.
+
+A common use case would be to package an app and all it's requirements in a container. The container can then be used during development, passed to quality assurance/testing, and on to production/operations. This eliminates the "works on my machine" mentality, as the container effectively _is_ the machine, no matter what actual hardware it may be running on.
+
+After you are done setting up your computer and installig docker, you can simply test your Docker by running command:
+
+```shell
+$ docker run hello-world
+Unable to find image 'hello-world:latest' locally
+latest: Pulling from library/hello-world
+ca4f61b1923c: Pull complete
+Digest: sha256:ca0eeb6fb05351dfc8759c20733c91def84cb8007aa89a5bf606bc8b315b9fc7
+Status: Downloaded newer image for hello-world:latest
+
+Hello from Docker!
+This message shows that your installation appears to be working correctly.
+...
+```
+If you have no hello-world image locally Docker will automatically download it to your machine.
+You can list image that was downloaded or created to your machine by running command:
+
+```shell
+$ docker image ls
+```
+
+
+[Docker Store](https://hub.docker.com/explore/) contains many common applications packaged up into containers and ready to be used.
+
+## Further reading
+* [Docker Documentation](https://docs.docker.com)