Packer

What is Packer ?

Packer gives the ability to automate image builds. It will allow us to create customized template with pre-defined generic configuration.

List of supported configuration

Version is pinned in configuration file.

Hypervisors:

• Proxmox

Distributions :

• Ubuntu

How does it works ?

sequenceDiagram
    actor User
    User->>Packer: Launch packer command
    Packer->>Hypervisor: Connect to hypervisor API<br>and ask hypervisor to create VM
    create participant VM
    Hypervisor->>VM: Create and start VM
    Packer->>VM: Typing boot sequence<br>and tell the VM to connect to Packer HTTP server<br>to get cloud init configuration
    Packer->>Packer: Start HTTP server<br>and serve rendered cloud init configuration template<br>(minimal configuration)
    VM->>Packer: Download configuration through HTTP
    VM->>VM: Proceed to autoinstall<br>and reboot at the end
    Packer->>Packer: Waiting availability of SSH server
    Packer->>VM: SSH to the VM<br> and wait end of cloud init execution
    Packer->>VM: Execute ansible playbook deploy_packer.yml<br>to finish VM configuration
    Packer->>Packer: Shutdown VM,<br>remove CD-ROM,<br>convert VM to template<br>and stop HTTP server

How to open/close ports ?

PORT represents the packer http server port

• Open port

  IptablesUfw

  iptables -A INPUT -p tcp --dport <PORT> -j ACCEPT -m comment --comment "Packer"
  

  ufw allow <PORT>/tcp comment "Packer"
  

• Close port

  IptablesUfw

  iptables -D INPUT -p tcp --dport <PORT> -j ACCEPT -m comment --comment "Packer"
  

  ufw delete allow <PORT>/tcp
  

How to expose packer HTTP server from WSL ?

WINDOWS IP represents the IP used to connect
WINDOWS PORT represents the port used to connect
WSL_IP represents the packer http server ip that will be accessible through <WINDOWS IP>:<WINDOWS PORT>
WSL PORT represents the packer http server port that will be accessible through <WINDOWS IP>:<WINDOWS PORT>

• To create a port forwarding rule open powershell prompt with admin right

  New-NetFirewallRule -DisplayName 'Packer' -Direction Inbound -Protocol TCP -LocalPort <WINDOWS PORT> -Action Allow
  netsh interface portproxy add v4tov4 listenaddress=<WINDOWS IP> connectaddress=<WSL_IP> listenport=<WINDOWS PORT> connectport=<WSL PORT>
  

• To delete a port forwarding rule open powershell prompt with admin right

  Remove-NetFirewallRule -DisplayName 'Packer'
  netsh interface portproxy del v4tov4 listenaddress=<WINDOWS IP> listenport=<WINDOWS PORT>
  

Usage

Configuration is stored in packer folder.

Packer use 8888/tcp port for this HTTP server.

PROXMOX_PASSWORD represents the proxmox password used for HTTP API

cd packer
packer build \
  -var "proxmox_password=<PROXMOX_PASSWORD>" \
  -timestamp-ui \
  templates/ubuntu