Document how to customize VM image

[coolaj86]

libguestfs & cloud-init

sudo apt update -y && sudo apt install libguestfs-tools -y

• https://docs.digitalocean.com/products/droplets/how-to/provide-user-data/
• https://www.cyberciti.biz/faq/run-commands-on-linux-instance-at-launch-using-cloud-init/
• https://austinsnerdythings.com/2021/08/30/how-to-create-a-proxmox-ubuntu-cloud-init-image/
• https://www.digitalocean.com/blog/custom-images

[coolaj86]

I think I've found a decent way to do this with cloud-init and mounting + chroot.

I'll just copy what I started on here:

#!/bin/sh
set -e
set -u

main() {(
        # See names of pools (i.e. pool0, cephfs0, local, local-lvm)
        # pvesm status

        b_vm_name="ubuntu-24-04-lts-1106"

        #         101102001
        qm create 924041106 \
                --memory 96 \
                --core 2 \
                --name "${b_vm_name}" \
                --net0 virtio=00:52:40:96:00:01,bridge=vmbr1,tag=4094
        if ! qm list | grep -F "${b_vm_name}"; then
                echo "did not create '${b_vm_name}'"
                return 1
        fi

        if !  qm disk import 924041106 'iso/ubuntu-noble-24_04_lts_1106-server-cloudimg-x86_64.img' 'pool0'; then
               pvesm list 'cephfs0'
               return 1
        fi

        # or scsihw=virtio-scsi-pci ?
        qm set 924041106 --scsihw virtio-scsi-single --scsi0 'pool0':'vm-924041106-disk-0',ssd=1
        qm set 924041106 --ide2 pool0:cloudinit
        qm set 924041106 --boot c --bootdisk scsi0
        qm set 924041106 --serial0 socket --vga serial0
        qm set 924041106 --cpu host
        qm template 924041106
);}

fn_api() {(
        # qm resize 924041106 scsi0 8G

        curl 'https://pve3.example.com/api2/extjs/nodes/pve3/qemu/924041106/clone' \
          -H 'Origin: https://pve3.example.com' \
          --data-raw 'newid=100&name=ajbuntu-1&target=pve3&full=1'
                'newid=100&name=ajbuntu-1&target=pve3&full=1'


        curl 'https://pve3.example.com/api2/extjs/nodes/pve3/qemu/100/config' \
          -X 'PUT' \
          --data-raw 'net0=virtio%3D00%3A52%3A11%3A01%3A00%3A44%2Cbridge%3Dvmbr1%2Ctag%3D1101&digest=0798ef7bf50b0865fdaab9ed21aadb751a4aaed2'

        curl 'https://pve3.example.com/api2/extjs/nodes/pve3/qemu/100/resize' \
          -X 'PUT' \
          --data-raw 'disk=scsi0&size=%2B2G'

        # TODO: CPU + Memory Hotplug, NUMA
        # REQURIES minimum 1024mb RAM, loses 129MB
        # (hotswap memory works automatically, cpu doesn't)
        # https://pve.proxmox.com/wiki/Hotplug_(qemu_disk,nic,cpu,memory)#CPU_Hotplug
        # &hotplug=disk%2Cnetwork%2Cusb%2Cmemory%2Ccpu
        # &numa=1&sockets=1&cores=3&cpu=host&delete=vcpus%2Caffinity%2Ccpuunits%2Ccpulimit

        # &ciuser=app
        # &ostype=l26
        # &memory=128&delete=balloon%2Cshares
        # &scsi1=pool0%3A0.1%2Cssd%3Don%2Ciothread%3Don
        # &scsi0=pool0%3Avm-100-disk-0%2Csize%3D3584M%2Cssd%3Don%2Ciothread%3Don
        # &sockets=1&cores=3&numa=0&cpu=host&delete=vcpus%2Caffinity%2Ccpuunits%2Ccpulimit
        # &sockets=1&cores=4&vcpus=3&cpulimit=1.8&cpuunits=2&numa=0&cpu=host&delete=affinity
        # &searchdomain=1101.c.example.com
        # &nameserver=172.17.0.1
        # &sshkeys=ssh-ed25519%2520AAAAC3NzaC1lZDI1NTE5AAAAIFtHxl7p%252F1ko1aTygdNa884u9Hl3PNPjCaMppDwpopbI%2520aj%2540biggoron-2024.ed.local%250Assh-ed25519%2520AAAAC3NzaC1lZDI1NTE5AAAAINkmityQSVxuyugzaSY2utON35datfo6MXyTut%252Bt4PEY%2520aj%2540boomerang-2024.ed.local
        # &ipconfig0=ip%3D10.11.1.47%2F24%2Cgw%3D10.11.1.1
        # &name=ajbuntu-1.1101.c.example.com
        # &onboot=1
);}

fn_udev_rules() {(
        # so far this doesn't seem to work
        echo 'SUBSYSTEM=="cpu", ACTION=="add", TEST=="online", ATTR{online}=="0", ATTR{online}="1"' | tee /lib/udev/rules.d/80-hotplug-cpu.rules
        udevadm control --reload-rules && udevadm trigger
        #sudo systemctl restart udev
);}

main