Vagrant OEL 8 DevOps · VirtualBox · Networking

Vagrant — Networking for OEL 8 VMs

Master Vagrant networking — NAT port forwarding, private host-only networks, public bridged networks and multi-network database lab designs for OEL 8.

Vagrant Networking Overview

Vagrant provides four networking modes for OEL 8 VMs. Each serves a different purpose — from isolated private networks for database clusters to bridged networks for public accessibility. Understanding each is essential for database lab setups.

Networking Modes Comparison

Mode	VM accessible from	VM can access	Use case
NAT (default)	Host only via port forward	Internet via host	Single VM, internet access
Private Network	Host machine only	Host + other private VMs	DB clusters, replication labs
Public Network	Any machine on network	Full network	Testing from other machines
Internal Network	Other VMs only	Other VMs only	Isolated VM-to-VM only

Port Forwarding (NAT)

NAT is the default adapter. Port forwarding maps a host port to a VM port — the VM is not directly accessible but specific ports are reachable.

Ruby — Port Forwarding

Vagrant.configure("2") do |config|
  config.vm.box = "generic/oracle8"

  # MySQL port
  config.vm.network "forwarded_port", guest: 3306, host: 13306

  # Oracle port
  config.vm.network "forwarded_port", guest: 1521, host: 11521

  # ProxySQL ports
  config.vm.network "forwarded_port", guest: 6033, host: 16033
  config.vm.network "forwarded_port", guest: 6032, host: 16032

  # Web / phpMyAdmin
  config.vm.network "forwarded_port", guest: 80, host: 8080

  # Custom SSH port (avoid conflict with default 2222)
  config.vm.network "forwarded_port", guest: 22, host: 2200,
    id: "ssh", auto_correct: true

end

BASH — Use Port Forwarding

# Connect to MySQL via port forward from host
mysql -u root -h 127.0.0.1 -P 13306

# Connect to Oracle via port forward
sqlplus sys/password@//127.0.0.1:11521/ORCLCDB as sysdba

# View all forwarded ports
vagrant port

Private Network (Host-Only)

Private network creates a network only between your host machine and the VM. No other machines on your network can reach the VM. Perfect for database replication labs.

Ruby — Private Network

Vagrant.configure("2") do |config|
  config.vm.box = "generic/oracle8"

  # Static IP (recommended for databases)
  config.vm.network "private_network", ip: "192.168.56.10"

  # DHCP (IP assigned automatically — changes between restarts)
  # config.vm.network "private_network", type: "dhcp"

end

BASH — Use Private Network

# Test private network from host
ping 192.168.56.10

# Connect to MySQL via private IP
mysql -u root -h 192.168.56.10 -P 3306

# Connect via SSH directly (bypasses vagrant ssh)
ssh vagrant@192.168.56.10

Public Network (Bridged)

Public network bridges the VM to your physical network adapter — the VM gets an IP on your local network and is accessible from other machines.

Ruby — Public Network

Vagrant.configure("2") do |config|
  config.vm.box = "generic/oracle8"

  # Auto-select bridge adapter
  config.vm.network "public_network"

  # Specify bridge adapter (use exact name from your machine)
  config.vm.network "public_network", bridge: "en0: Wi-Fi"

  # Static IP on public network
  config.vm.network "public_network",
    bridge: "en0: Wi-Fi",
    ip: "192.168.1.100"

end

BASH — Find Bridge Adapters

# Find bridge adapter names on macOS
VBoxManage list bridgedifs | grep "^Name:"

# Find bridge adapter names on Linux
ip link show

Multiple Networks

VMs can have multiple network adapters — common in database setups where you need both a management network and a replication network.

Ruby — Multiple Networks

Vagrant.configure("2") do |config|
  config.vm.box = "generic/oracle8"

  # Management network (connect from host)
  config.vm.network "private_network", ip: "192.168.56.10"

  # Replication network (VM-to-VM only)
  config.vm.network "private_network", ip: "10.0.0.10"

  # MySQL port forward via NAT
  config.vm.network "forwarded_port", guest: 3306, host: 13306

end

Database Lab Network Design

For a typical MySQL Master + Replica + ProxySQL lab:

Ruby — Database Lab Network

Vagrant.configure("2") do |config|

  # ProxySQL
  config.vm.define "proxysql" do |p|
    p.vm.box     = "generic/oracle8"
    p.vm.hostname = "proxysql"
    p.vm.network "private_network", ip: "192.168.56.10"
    p.vm.network "forwarded_port", guest: 6033, host: 16033
    p.vm.network "forwarded_port", guest: 6032, host: 16032
  end

  # MySQL Master
  config.vm.define "master" do |m|
    m.vm.box     = "generic/oracle8"
    m.vm.hostname = "mysql-master"
    m.vm.network "private_network", ip: "192.168.56.11"
    m.vm.network "forwarded_port", guest: 3306, host: 13306
  end

  # MySQL Replica
  config.vm.define "replica" do |r|
    r.vm.box     = "generic/oracle8"
    r.vm.hostname = "mysql-replica"
    r.vm.network "private_network", ip: "192.168.56.12"
    r.vm.network "forwarded_port", guest: 3306, host: 13307
  end

end