docs: update alpine_cloudinit.tf example for v0.9.1 schema changes

[hpst3r]

update alpine_cloudinit.tf example so it validates and applies under v0.9.1, ref issue #1243

[schober-ch]

Not sure if I'm doing it wrong, but I tried to run the updated example with the latest version 0.9.1 and it fails to boot. I'm new to libvirt and currently fail to capture any useful logs other than what I see with virt-viewer, but once I figure it out I'll provide some details

[hpst3r]

Hi @schober-ch - what's the target system? I suppose I should have mentioned that I tested against an AlmaLinux 10 box with Libvirt 11.5.0 and was running Terraform 1.14.

I just (tonight) ran this against another Alma 10 machine (Libvirt 11.5) with success and a Fedora 42 machine (Libvirt 11.0) with a failure (see below). Unfortunately those three hosts are all I have accessible at the moment.

The failure on the Fedora machine seems to be related to the virtio disk driver in pre-11.5 libvirt & this version of Alpine; swapping to SCSI fails the same way (unable to mount /) but swapping to the emulated SATA bus sees the guest boot successfully:

If you're seeing the same error, can you try to adjust the devices { disks [] } segment (line 106 - 135) from:

    disks = [
      {
        source = {
          volume = {
            pool   = libvirt_volume.alpine_disk.pool
            volume = libvirt_volume.alpine_disk.name
          }
        }
        target = {
          dev = "vda"
          bus = "virtio"
        }
        driver = {
          type = "qcow2"
        }
      },
      {
        device = "cdrom"
        source = {
          volume = {
            pool   = libvirt_volume.alpine_seed_volume.pool
            volume = libvirt_volume.alpine_seed_volume.name
          }
        }
        target = {
          dev = "sda"
          bus = "sata"
        }
      }
    ]

To:

    disks = [
      {
        source = {
          volume = {
            pool   = libvirt_volume.alpine_disk.pool
            volume = libvirt_volume.alpine_disk.name
          }
        }
        target = {
          dev = "sda"
          bus = "sata"
        }
        driver = {
          type = "qcow2"
        }
      },
      {
        device = "cdrom"
        source = {
          volume = {
            pool   = libvirt_volume.alpine_seed_volume.pool
            volume = libvirt_volume.alpine_seed_volume.name
          }
        }
        target = {
          dev = "sdb"
          bus = "sata"
        }
      }
    ]

I did notice that an "ERROR: cloud-final failed to start" is coming up once the guest does boot, which I didn't notice last weekend. I'll see if I have some time to troubleshoot later on.

[schober-ch]

As usual I got distracted from this project by other responsibilities, but I tested on an Arch Linux laptop. libvirt 11.10.0. I will get back to this after Christmas (I hope) and then try some systematic testing.