Builders for creating/cloning containers (CTs)

[chrisbenincasa]

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Description

New builders for creating and cloning CTs (containers) and / or converting them into templates

Use Case(s)

Containers are a core feature of Proxmox, alongside VMs. It would be useful to automate the creation of container templates, etc.

Potential configuration

I have a minimal working version of container creation in my fork of the plugin. I'd be happy to take a stab at implementing the new builders! The configuration I have looks like:

source "proxmox-ct" "test" {
  username                 = "${var.pve_api_token_id}"
  token                    = "${var.pve_api_token_secret}"
  proxmox_url              = "${var.pve_url}"
  node                     = "zeus"
  insecure_skip_tls_verify = true
  os_template              = "local:vztmpl/debian-11-standard_11.6-1_amd64.tar.zst"
  storage                  = "local-zfs"

  cores     = 1
  cpu_limit = 500
  memory    = 512

  network_interfaces {
    name     = "eth0"
    bridge   = "vmbr0"
    firewall = false
    ip       = "dhcp"
  }

  user_password = "${var.user_password}"

  start = true
}

build {
  sources = ["sources.proxmox-ct.test"]

  provisioner "shell" {
    inline = [
      "ls /"
    ]
  }
}

Potential References

https://pve.proxmox.com/pve-docs/api-viewer/#/nodes/{node}/lxc
https://pve.proxmox.com/pve-docs/api-viewer/#/nodes/{node}/lxc/{vmid}/template

[chrisbenincasa]

Update on my attempt here, here's the WIP: https://github.com/hashicorp/packer-plugin-proxmox/compare/main...chrisbenincasa:packer-plugin-proxmox:ct-create?expand=1

Few notes:

• Currently, this is able to create CT templates, very similar to how the ISO builder works for VMs
• It requires SSH access to the Proxmox host itself, which is sort of unfortunate. This is necessary because the Proxmox API does not expose the DHCP-assigned IP addresses for a container in the same way it does for VMs that have the QEMU agent running. This is a long standing issue in Proxmox itself: https://bugzilla.proxmox.com/show_bug.cgi?id=2602
  • The provisioning method works by SSH'ing into the host and then proxying a series of pct exec commands to run inside of the container. This functionality also isn't exposed by the API
  • I'm still working on some of the more complex interactions, like uploading an entire directory into the container. pct push / pull is limited to single files and working within the confines of running these over SSH is even more limiting.

[newedgex]

This is a very good improvement , it's a must have to automate basically everything with packer

[haxwithaxe]

It appears the missing piece is in APIv2 https://pve.proxmox.com/pve-docs/api-viewer/index.html#/nodes/{node}/lxc/{vmid}/interfaces

[chrisbenincasa]

It's been a while but if I remember correctly, that API endpoint will only return an IP address if it was statically assigned by the host node and not if DHCP was used

[haxwithaxe]

I just tested with an LXC container configured to use DHCP. The API gives me the IP given by DHCP. :)

pvesh get /nodes/ank/lxc/104/interfaces --noborder
hwaddr            name inet              inet6
00:00:00:00:00:00 lo   127.0.0.1/8       ::1/128
bc:24:11:39:62:84 eth0 192.168.10.219/24 fe80::be24:11ff:fe39:6284/64

[chrisbenincasa]

Oh that's awesome! That will definitely simplify the implementation

[emaiax]

hey @chrisbenincasa, outstanding work you have in the PR. This is definitely a must have to build images and container templates on my homelab. Do you know if it's far from stable or it can be used as is?