RancherOS Getting Started Guide

A guide about running Rancher’s Container OS inside virtual machine and launching Docker Containers from within. Also guide to setup Rancher Server (a container management platform) as docker container inside RancherOS for demo. Rancher Server’s docker container can also be run elsewhere.

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**Table of Contents**

[TOCM]

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### All About: Rancher OS

#### RancherOS

[RancherOS](https://rancher.com/rancher-os/) is an ultra-light (*around 69-100MB*) linux operating system dedicated to running docker containers. Basically:
- RancherOS is very thin nothing else installed only busybox, system-docker and docker. It makes it simple to run containers at scale in development, test and production. It's a pure **Container OS**
- Being thin linux only basic linux commands will only work like for IP checking use `/sbin/ifconfig | less`. Even commands like apt etc. are not present so its would be tough to operate.
- RancherOS uses `system-docker` to wrap `docker` so you've to use `sudo system-docker run ...` commands instead of `docker run ...`

Please refer to [QuickStart RancherOS](http://rancher.com/docs/os/v1.2/en/quick-start-guide/) for more understanding of sub-section A and B

##### A. Installation

1. Download RancherOS distribution from github repository [https://github.com/rancher/os/releases](https://github.com/rancher/os/releases). To get right release go to home page [https://rancher.com/rancher-os/](https://rancher.com/rancher-os/) and then click **Download Rancher OS**. This will take you to same github repo but right release. For time being use [RancherOD v1.1.4](https://github.com/rancher/os/releases/tag/v1.1.4)
2. Each github release contains - `rancheros.iso` just when you want to boot from iso and keep working (*no install live disk*). But after reboot all docker containers will be gone. So you can instead use RancherOS inside a Virtual Machine like VMWare workstation etc. In order to run it as virtual machine proceed as follows:
  - Download virtual disk image for RancherOS named as `rancheros-aliyun.vhd` then use VHD to VMDK converter like [WinImage](http://www.winimage.com/download.htm) to convert this VHD into `rancheros-aliyun.vmdk`. **Make sure to convert it into an expandable disk**. Expansion will be required to grow disk when docker images are pulled into it.
  - Create a virtual machine named *RancherOS (x64)* with suitable hardware, just remove hard disk and add converted `rancheros-aliyun.vmdk` in place of it and reboot. Make sure that network is configured to **Host-Only: A Private Network Shared with the Host** for this example
  - Boot your virtual machine you'll be taken to shell of RancherOS. Type `sudo system-docker ps` to verify that RancherOS default service as docker containers are running.

##### B. Running Containers

1. First execute `docker run hello-world` inside OS with active internet to ensure that docker system is fine. Also execute `sudo system-docker ps` to verify system-docker
2. Find IP address of RancherOS using `/sbin/ifconfig | less` command. IP will be availaible against interface **eth0**. Use `q` key to come out of editor, in this case IP adress was `192.168.139.128`
3. Use conventional docker commands to execute containers replacing `docker` with `suck system-docker` like
  - Run containers using `sudo system-docker run ...`
  - Delete containers using `sudo system-docker rm -f ...`
  - etc.
4. Lets launch a RancherOS monitoring dashboard docker container by executing `sudo system-docker run -d --net=host --name busydash husseingalal/busydash`. Once running you can see monitoring over IP adress in a browser at [http://192.168.139.128](http://192.168.139.128)

[![IMAGE NOT FOUND](http://rancher.com/docs/img/os/Rancher_busydash.png)](http://rancher.com/docs/img/os/Rancher_busydash.png "OnMouseOver Anchor Text")
<p class="imgCaption">[]()RancherOS Dashboard. [See Quickstart Guide](http://rancher.com/docs/os/v1.2/en/quick-start-guide/) for more details
</p>

To make the container survive during the reboots, you can create the /opt/rancher/bin/start.sh script, and add the Docker start line to launch the Docker at each startup. Restart using `sudo shutdown -r` command.

```bash
$ sudo mkdir -p /opt/rancher/bin
$ echo "sudo system-docker start busydash" | sudo tee -a /opt/rancher/bin/start.sh
$ sudo chmod 755 /opt/rancher/bin/start.sh
```

#### Rancher
[RancherOS](https://rancher.com/rancher-os/) is begning of container orchestration, Rancher company also provide [Rancher](http://rancher.com/rancher2-0/) **container management platform**. That means:
- [Rancher](http://rancher.com/rancher2-0/) container managerment platform product can be used to manage contrainer using its web based dashboard and run clusters.

##### Highlights

- Rancher is _**not a container orchestrator**_, it' a complete container management platform that includes everything you need to manage containers in production. You can *quickly dpeloy multiple Docker as well as Kubernetes* clusters *across clouds* with click of a button. 
- This is amazing, both docker and kubernetes containers controlled by Rancher's UI and in any cloud (*even private*) - unlike AWS does only only Amazon and Kubernetes in GCE. **With Rancher Private & Hybrid Cloud Becomes Reality**
- For private cloud you may use RancherOS. RancherOS is an ultra-lightweight Linux distribution which enables you to boot Your containers in seconds as well as run Docker, Kubernetes and Rancher at *Scale in production* that too with High Availaibility options.
- Most awsome part is Rancher [application catalogue](http://www.rancher.com/catalog-items/). It helps you deploy and scale applications with click of a button, No more need to build docker or kubernetes for apps. If you prefer Kubernetes and Helm? No problem. Helm is included out of the box. Around 90 popular docker applications like jenkins etc. are availaible.
- WoW - imagine Rancher spin up kubernetes+docker+mesos custom cluser, docker container for mail server and pre-ready jenkins scaled app with hybrid deployment to amazon, gce and your own cloud with clicks. **Years in Days**

##### Demonstration

Watch following video for demonstration on Rancher to spin up Kubernetes cluster. **_It's a must watch_**

**RancherOS can be used to launch Rancher and be used as the OS to add hosts to Rancher.**

##### Launch Rancher Server (UI)

- Rancher Server can be launched anywhere it's official docker image is availaible as `Rancher/server:stable`. We shall launch this inside docker of RancherOS and not Windows Docker for fun. RancherOS itself is running in VMWare on Windows or it could be directly installed to HDD.
- Execute `sudo system-docker run -d --net=host --restart=unless-stopped -p 81:8080 Rancher/server:stable` in Rancher OS to start server. Now you've to add hosts to this server so that server can deploy containers to hosts.
- Cool thing is in future I'll try is to add same RancherOS host that's running Rancher Server Container to Rancher Server. This way Rancher Server can spin containers on it's own host
- Pull docker image of Rancher server using `sudo system-docker pull rancher/server:stable`. In case of connectivity error temporarily change virtual machin's networking to NAT from Private and once `rancher/server:stable` is pulled, shutdown using `sudo shutdown` and change network to *PRIVATE*. Reboot RancherOS and verify image and ip using `sudo system-docker images`, `sudo system-docker ps` and `/sbin/ifconfig | less`.
- Run server using `sudo system-docker run -d --net=host --name rancher_server --restart=unless-stopped -p 8080:8080 rancher/server:stable` than use [http://192.168.139.128:8080](http://192.168.139.128:8080) to browse the server after 2-3 minutes (*time for server to get ready*). Type `echo "sudo system-docker start rancher_server" | sudo tee -a /opt/rancher/bin/start.sh` to make it auto start.