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Metron on CentOS 6
==================

This project fully automates the provisioning and deployment of Apache Metron and all necessary prerequisites on a single, virtualized host running CentOS 6.

Metron is composed of many components and installing all of these on a single host, especially a virtualized one, will greatly stress the resources of the host.   The host will require at least 8 GB of RAM and a fair amount of patience.  It is highly recommended that you shut down all unnecessary services.

Getting Started
---------------

### Prerequisites

The computer used to deploy Apache Metron will need to have the following components installed.

 - [Ansible](https://github.com/ansible/ansible) (2.0.0.2, 2.2.2.0, or 2.5.0)
 - [Docker](https://www.docker.com/community-edition)
 - [Vagrant](https://www.vagrantup.com) 2.0+
 - [Vagrant Hostmanager Plugin](https://github.com/devopsgroup-io/vagrant-hostmanager)
 - [Virtualbox](https://virtualbox.org) 5.0+
 - Python 2.7
 - Maven 3.3.9
 - C++11 compliant compiler, like [GCC](https://gcc.gnu.org/projects/cxx-status.html#cxx11)

Running the following script can help validate whether you have all the prerequisites installed and running correctly.

  ```
  metron-deployment/scripts/platform-info.sh
  ```

#### How do I install these on MacOS?

Any platform that supports these tools is suitable, but the following instructions cover installation on macOS.  The easiest means of installing these tools on a Mac is to use the excellent [Homebrew](http://brew.sh/) project.

1. Install Homebrew by following the instructions at [Homebrew](http://brew.sh/).

1. Run the following command in a terminal to install all of the required tools.

    ```
    brew cask install vagrant virtualbox docker
    brew cask install caskroom/versions/java8
    brew install maven@3.3 git
    pip install ansible==2.2.2.0
    vagrant plugin install vagrant-hostmanager
    open /Applications/Docker.app
    ```

### Deploy Metron

1. Ensure that the Docker service is running.

1. Deploy Metron

    ```
    cd metron-deployment/development/centos6
    vagrant up
    ```

    Should the process fail before completing the deployment, the following command will continue the deployment process without re-instantiating the host.

    ```
    vagrant provision
    ```

### Explore Metron

Navigate to the following resources to explore your newly minted Apache Metron environment.

* [Metron Alerts](http://node1:4201) credentials: user/password
* [Ambari](http://node1:8080) credentials: admin/admin

Connecting to the host through SSH is as simple as running the following command.
```
vagrant ssh
```

### Working with Metron

In addition to re-running the entire provisioning play book, you may now re-run an individual Ansible tag or a collection of tags in the following ways.  The following commands will re-run the `sensor-stubs` role on the Vagrant image. This will install and start the sensor stub components.

```
vagrant --ansible-tags="sensor-stubs" provision
```

Tags are listed in the playbooks, some frequently used tags:
+ `hdp-install` - Install HDP
+ `hdp-deploy` - Deploy and Start HDP Services (will start all Hadoop Services)
+ `sensors` - Deploy and start the sensors.
+ `sensor-stubs` - Deploy and start the sensor stubs.