Home Lab As Code

This repository provides a way to easily create and manage virtual machines on your local machine. It uses Packer to generate cloud-init ready Red Hat Enterprise Linux (RHEL) images, and Terraform to automate the provisioning of virtual machines. The included dnsmasq configuration makes the virtual machines resolvable from the local machine using the home.arpa domain. Additionally, after the provisioning process with Terraform, it will create an updated ansible inventory that can be used for further management and configuration of the provisioned machines.

Prerequisites

• Have ansible installed on your system
• Have packer installed on your system
• Have terraform installed on your system
• Red Hat Enterprise Linux (RHEL) based distribution

Downloading Content

Download ISO files

To create the RHEL images, you'll need to download the appropriate ISO files and place them in the packer/iso-files directory. Check the rhel8.pkr.hcl and rhel9.pkr.hcl packer config files to see which ISO files are needed.

Building Packer Images

To build the Packer images, follow these steps:

cd packer/<rhel_version>
packer init .
packer build .

Configuring libvirt

The libvirt configuration is based on the following instructions:
howto-automated-dns-resolution-for-kvmlibvirt-guests-with-a-local-domain.
This configuration uses home.arpa for the domain name. (see rfc8375).

Edit libvirt Local Domain

You'll need to configure the default libvirt network to use the home.arpa domain. To check the current network configuration, run the following command:

sudo virsh net-dumpxml default

Example output:

<network connections='1'>
  <name>default</name>
  <uuid>158880c3-9adb-4a44-ab51-d0bc1c18cddc</uuid>
  <forward mode='nat'>
    <nat>
      <port start='1024' end='65535'/>
    </nat>
  </forward>
  <bridge name='virbr0' stp='on' delay='0'/>
  <mac address='52:54:00:fa:cb:e5'/>
  <domain name='home.arpa' localOnly='yes'/>
  <ip address='192.168.122.1' netmask='255.255.255.0'>
    <dhcp>
      <range start='192.168.122.128' end='192.168.122.254'/>
    </dhcp>
  </ip>
</network>

Make sure the network configuration contains the following:

<domain name='home.arpa' localOnly='yes'/>

If it's not, you can edit the configuration by running the following command:

virsh net-edit default

Configuring dns masquerading

To enable DNS masquerading, you'll need to make a few changes to your system's DNS settings. First, add the following line to /etc/NetworkManager/conf.d/localdns.conf:

[main]
dns=dnsmasq

Then, add the following line to /etc/NetworkManager/dnsmasq.d/libvirt_dnsmasq.conf:

server=/home.arpa/192.168.122.1

Finally, restart the NetworkManager service:

sudo systemctl restart NetworkManager

Using Terraform to deploy VMs

To deploy the VMs using the built images, navigate to the terraform directory and follow these steps:

Variables

1. Copy terraform.tfvars.example to terraform.tfvars (or another name that ends with .tfvars)
2. Fill out your terraform.tfvars file
3. Run terraform init to initialize the directory that contains a Terraform configuration
4. Run terraform plan -var-file=terraform.tfvars to evaluate a Terraform configuration to determine the desired state
5. Run terraform apply -var-file=terraform.tfvars to carry out the planned changes to each resource

note: you can auto load the tfvars file without the -var-file=terraform.tfvars by putting auto in the name. For example: terraform.auto.tfvars

Using Ansible to provision VMs

The playbooks in the ansible directory can be used to provision the VMs deployed by terraform. You can use ansible-playbook command to run the playbooks. During the terraform deployment a ansible.cfg is created containing the user that is specified in the variables.tf file. The default user is cloud-user. Also the ansible/inventory/hosts is updated with the new information via terraform.

Troubleshooting

In case of issues or errors, check the following:

• Make sure the appropriate versions of packer and terraform are installed.
• Check that the ISO files are in the correct directory and that the paths in the packer config files are correct.
• Verify that the NetworkManager service is running and properly configured.

Additional Resources

• Ansible documentation
• Packer documentation
• Terraform documentation
• Libvirt documentation

Please note that some commands and file paths may be different depending on your operating system and specific setup.

Licensing

This repository is licensed under the MIT license. Refer to the LICENSE file for details.

This project can serve as a great starting point for automating your home lab infrastructure and can be easily customized to suit your specific needs.