Virtual Machine Installation

Virtual Machine Installation

A guide for setting up a virtual machine with a linux/red hat OS. This can assist with local testing in an isolated environment and is especially useful for testing your Ansible provisioning playbook. The chap-press repo can be used with Ansible & Capistrano to test locally on a virtual machine.

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For a checklist using the command line, see https://wimops.chapman.edu/wiki/VirtualBox

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Quick Links

SSH access
Web access
Firewall
Snapshot

Requirements

• Virtual Box (5.1.26 >=)
• CentOS 7 (Minimal ISO)

Setup

Create Virtual Machine and Install OS

• Install Virtual Box. Using homebrew:

  brew cask install virtualbox
  

• Open Virtual Box and click new

• Name your virtual machine

  • Choose linux as the type
  • Red Hat (64-bit) as the version

• Continue with suggested memory size

• Continue with suggested hard disk size

• Continue with default hard disk type (VDI)

• Continue with default option for storage (dynamically allocated)

  The virtual box should now contain a virtual machine that is powered off.

• Click the start option at the toolbar

• Select CentOS .iso downloaded file from your computer

• Follow through CentOS install guide

  • Setup username wimops and password chapman123 (will be used for ssh)

• Install will complete and click the reboot button

  Once the VM reboots, you will be able to login in at the VM terminal.

Setup SSH access on the VM

The CentOS currently does not have access to the internet.

• Check in terminal: ip addr

• Change configuration for internet access

  sudo vi /etc/sysconfig/network-scripts/ifcfg-enp0s3
  # Change ONBOOT line to yes: ONBOOT=yes
  reboot 
  

CentOS minimal comes with an ssh server so the last step needed to be able to ssh in from our local machine is to setup port forwarding on our VM. Note: If VM has been installed previously, remove localhost:2222 key from ~/.ssh/known_hosts

• Select Settings button & Network tab
• Click Advanced down arrow & click Port Forwarding button
  This will allow us to ssh into the VM.
• Enter the following settings:
  • Host IP: 127.0.0.1
  • Host Port: 2222 (or any open local port)
  • Guest IP: this is the ip addr typed in the VM (10.0.2.15)
  • Guest Port: 22 (default ssh port)
• Click OK and you should now be able to ssh in from the local terminal.
  ssh-copy-id -p 2222 wimops@localhost
ssh -p 2222 wimops@localhost

Enable web access to VM Port

If a server is installed on the VM, this will allow public access to a specific port.

• On VirtualBox, select machine and click settings icon
• Click Network icon
• Click Advanced dropdown and click Port Forwarding
• Click the plus icon to add a new port forwarding rule
• Enter the following settings:
  • Host IP: 127.0.0.1
  • Host Port: 5555 (or any open local port)
  • Guest IP: 10.0.2.15 (keep as same as VM)
  • Guest Port: 80 (or server port)

Allow access through the CentOS Firewalld app

The firewall settings on CentOS may not allow access to any ports from outside sources. This will allow a user to visit a site via their VM server.

If an Ansible role is not already defined for this:
Go to VM terminal:
Our port forwarding address example is 5555.

sudo firewall-cmd --zone=public --add-port=5555/tcp --permanent
sudo firewall-cmd --zone=public --add-port=80/tcp --permanent  
sudo firewall-cmd --reload
sudo firewall-cmd --zone=public --list-ports
# $ 5555/tcp

FirewallD Commands on CentOS
Installing Centos/VirtualBox

Setup a Snapshot

This can be used to save the state of your virtual machine before any major modifications. In this case, the snapshot is taken right after the previous configurations were setup. That way if any issues arise or harmful installations executed, the VM can be restored to exactly how it was before.

• Click Snapshots button (right side)
• Click Camera Icon for Snapshot ( or Ctrl-Shift-S)
• Choose an intuitive name and description (e.g. Clean Install Centos & Config)

The virtual machine snapshot is created.

Revert Snapshot

This will allow you to go back in time to the clean state just after the OS was installed.

• Shut down current VM
• Select the VM and click Snapshots button
• Click icon for restore (or right-click snapshot) and follow through with restore

The VM will revert itself back to the original snapshot.

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