Ansible Bootstrap

Automated Linux system bootstrap using the Arch Linux ISO as a universal installer. Deploys any supported distribution on virtual or physical targets via Infrastructure-as-Code.

Non-Arch targets require the appropriate package manager available from the ISO environment (e.g. dnf for RHEL-family). Set system.features.chroot.tool if arch-chroot is unavailable.

Table of Contents

1. Supported Platforms
2. Compatibility Notes
3. Configuration Model
4. Variable Reference
   • 4.1 Core Variables
   • 4.2 system Dictionary
   • 4.3 hypervisor Dictionary
   • 4.4 cis Dictionary
   • 4.5 VMware Guest Operations
   • 4.6 Multi-Disk Schema
   • 4.7 Advanced Partitioning Overrides
   • 4.8 Cleanup Defaults
5. Execution Pipeline
6. Usage
7. Security
8. Safety

1. Supported Platforms

Distributions

system.os	Distribution	system.version
almalinux	AlmaLinux	9, 10
archlinux	Arch Linux	latest (rolling)
debian	Debian	12, 13, unstable
fedora	Fedora	43, 44
rhel	Red Hat Enterprise Linux	9, 10
rocky	Rocky Linux	9, 10
ubuntu	Ubuntu (latest non-LTS)	optional (tracks 25.10 questing)
ubuntu-lts	Ubuntu LTS	optional (tracks 26.04 resolute)

Hypervisors

Hypervisor	hypervisor.type
libvirt	libvirt
Proxmox VE	proxmox
VMware	vmware
Xen	xen
Bare metal	none

2. Compatibility Notes

• rhel_iso is required for system.os: rhel.
• RHEL installs should use ext4 or xfs (not btrfs).
• custom_iso: true skips ArchISO validation; your installer must provide required tooling.
• On non-Arch installers, set system.features.chroot.tool explicitly.

3. Configuration Model

Two dict-based variables drive the entire configuration:

• system -- host, network, users, disk layout, encryption, and feature toggles
• hypervisor -- virtualization backend credentials and targeting

An optional third dict cis overrides CIS hardening parameters when system.features.cis.enabled: true.

All three are standard Ansible variables. Place them in group_vars/, host_vars/, or inline inventory. With hash_behaviour = merge, dictionaries merge across scopes, so shared values go in group vars and host-specific overrides go per-host.

Variable Placement

Location	Scope	Typical use
group_vars/all.yml	All hosts	Shared hypervisor, system.filesystem, boot_iso
group_vars/<group>.yml	Group	Environment-specific defaults
host_vars/<host>.yml	Single host	Host-specific overrides (system.network.ip, system.id, etc.)

Example Inventory

all:
  vars:
    system:
      filesystem: btrfs
    boot_iso: "local:iso/archlinux-x86_64.iso"
    hypervisor:
      type: proxmox
      url: pve01.example.com
      username: root@pam
      password: !vault |
        $ANSIBLE_VAULT...
      node: pve01
      storage: local-lvm

  children:
    bootstrap:
      hosts:
        app01.example.com:
          ansible_host: 10.0.0.10
          system:
            type: virtual
            os: debian
            version: "12"
            name: app01.example.com
            id: 101
            cpus: 2
            memory: 4096
            network:
              bridge: vmbr0
              ip: 10.0.0.10
              prefix: 24
              gateway: 10.0.0.1
              dns:
                servers: [1.1.1.1, 1.0.0.1]
                search: [example.com]
            disks:
              - size: 40
              - size: 120
                mount:
                  path: /data
                  fstype: xfs
            users:
              ops:
                password: !vault |
                  $ANSIBLE_VAULT...
                keys:
                  - "ssh-ed25519 AAAA..."
                sudo: true
            root:
              password: !vault |
                $ANSIBLE_VAULT...
            luks:
              enabled: true
              passphrase: !vault |
                $ANSIBLE_VAULT...
              method: tpm2
              tpm2:
                pcrs: "7"
            features:
              cis:
                enabled: true
              firewall:
                enabled: true
                backend: firewalld
                toolkit: nftables

4. Variable Reference

4.1 Core Variables

Top-level variables outside system/hypervisor/cis.

Variable	Type	Default	Description
boot_iso	string	--	Boot ISO path (required for virtual installs)
rhel_iso	string	--	RHEL ISO path (required when system.os: rhel)
custom_iso	bool	false	Skip ArchISO validation and pacman setup
thirdparty_tasks	string	dropins/preparation.yml	Drop-in task file included during environment setup

4.2 system Dictionary

Key	Type	Default	Description
type	string	virtual	virtual or physical
os	string	--	Target distribution (see table)
version	string	--	Version selector for versioned distros
filesystem	string	ext4	btrfs, ext4, or xfs
name	string	inventory hostname	Final hostname
timezone	string	Europe/Vienna	System timezone (tz database name)
locale	string	en_US.UTF-8	System locale
keymap	string	us	Console keymap
id	int/string	--	VMID (required for Proxmox)
cpus	int	0	vCPU count (required for virtual)
memory	int	0	Memory in MiB (required for virtual)
balloon	int	0	Balloon memory in MiB (Proxmox)
path	string	--	Hypervisor folder/path (falls back to hypervisor.folder)
mirror	string	per-distro default	Override package mirror (Debian/Ubuntu)
packages	list	[]	Additional packages installed post-reboot
network	dict	see below	Network configuration
disks	list	[]	Disk layout (see Multi-Disk Schema)
users	dict	{}	User accounts (keyed by username)
root	dict	see below	Root account settings
luks	dict	see below	Encryption settings
features	dict	see below	Feature toggles

system.network

Key	Type	Default	Description
bridge	string	--	Hypervisor network/bridge name
vlan	string/int	--	VLAN tag
ip	string	--	Static IP (omit for DHCP)
prefix	int	--	CIDR prefix (1-32, required with ip)
gateway	string	--	Default gateway
dns.servers	list	[]	DNS resolvers (must be a YAML list)
dns.search	list	[]	Search domains (must be a YAML list)
interfaces	list	[]	Multi-NIC config (overrides flat fields above)

When interfaces is empty, the flat fields (bridge, ip, prefix, gateway, vlan) are auto-wrapped into a single-entry list. When interfaces is set, it takes precedence. Each entry supports: name, bridge (required), vlan, ip, prefix, gateway.

system.users

Dict keyed by username. At least one user must have a password (used for SSH access during bootstrap). Users without a password get locked accounts (key-only auth).

system:
  users:
    svcansible:
      password: "vault_lookup"
      keys:
        - "ssh-ed25519 AAAA..."
    appuser:
      sudo: "ALL=(ALL) NOPASSWD: ALL"
      keys:
        - "ssh-ed25519 BBBB..."

Key	Type	Default	Description
(dict key)	string	--	Username (required)
password	string	--	User password (required for at least one user)
keys	list	[]	SSH public keys
sudo	bool/string	--	true for NOPASSWD ALL, or custom sudoers string

Users must be defined in inventory. The dict format enables additive merging across inventory layers with hash_behaviour=merge.

system.root

Key	Type	Default	Description
password	string	--	Root password
shell	string	/bin/bash	Login shell

system.luks

Key	Type	Default	Description
enabled	bool	false	Enable encrypted root
passphrase	string	--	Passphrase for format/open/enroll
mapper	string	SYSTEM_DECRYPTED	Mapper name under /dev/mapper
auto	bool	true	Auto-unlock toggle
method	string	tpm2	Auto-unlock backend: tpm2 or keyfile
keysize	int	64	Keyfile size in bytes
options	string	discard,tries=3	Additional crypttab options
type	string	luks2	LUKS format type
cipher	string	aes-xts-plain64	Cipher
hash	string	sha512	Hash algorithm
iter	int	4000	PBKDF iteration time (ms)
bits	int	512	Key size (bits)
pbkdf	string	argon2id	PBKDF algorithm

system.luks.tpm2

Key	Type	Default	Description
device	string	auto	TPM2 device selector
pcrs	string/list	--	PCR binding policy (e.g. "7" or "0+7"); empty = no PCR binding

TPM2 auto-unlock: Uses systemd-cryptenroll on all distros. The user-set passphrase remains as a backup unlock method. TPM2 enrollment runs in the chroot during bootstrap; if it fails (e.g. no TPM2 hardware), the system boots with passphrase-only unlock and TPM2 can be enrolled post-deployment via systemd-cryptenroll --tpm2-device=auto <device>.

On Debian/Ubuntu, TPM2 auto-unlock requires dracut (initramfs-tools does not support tpm2-device). The bootstrap auto-switches to dracut when method: tpm2 is set. Override via features.initramfs.generator.

system.features

Key	Type	Default	Description
cis.enabled	bool	false	Enable CIS hardening (see 4.4)
selinux.enabled	bool	true	SELinux management
firewall.enabled	bool	true	Firewall setup
firewall.backend	string	firewalld	firewalld or ufw
firewall.toolkit	string	nftables	nftables or iptables
ssh.enabled	bool	true	SSH service/package management
zstd.enabled	bool	true	zstd-related tuning
swap.enabled	bool	true	Swap setup
banner.motd	bool	false	MOTD banner
banner.sudo	bool	true	Sudo banner
chroot.tool	string	arch-chroot	arch-chroot, chroot, or systemd-nspawn
initramfs.generator	string	auto-detected	Override initramfs generator (see below)
rhel_repo.source	string	iso	RHEL post-install repo source: iso, satellite, or none
rhel_repo.url	string	--	Satellite/custom repo URL when source: satellite
secure_boot.enabled	bool	false	Enable Secure Boot (Arch via sbctl, others via shim)
secure_boot.method	string	--	Arch only: sbctl (default) or uki
desktop.*	dict	see below	Desktop environment settings (see 4.2.5)
firmware.*	dict	see below	Vendor firmware blobs and CPU microcode (see 4.2.6)
gpu.*	dict	see below	Mesa/Vulkan and per-vendor GPU userspace (see 4.2.7)
peripherals.*	dict	see below	Fingerprint readers, webcams, DisplayLink (see 4.2.8)
hardware.*	dict	see below	Hardware-detection profile override (see 4.2.9)

Initramfs generator auto-detection: RedHat -> dracut, Arch -> mkinitcpio, Debian/Ubuntu -> initramfs-tools. Override with dracut, mkinitcpio, or initramfs-tools. When LUKS TPM2 auto-unlock is enabled and the native generator does not support tpm2-device, the generator is automatically upgraded to dracut. On distros with older dracut (no tpm2-tss module), clevis is used as a fallback for TPM2 binding.

4.2.5 system.features.desktop

Key	Type	Default	Description
enabled	bool	false	Install desktop environment
environment	string	""	gnome, kde, sway, or hyprland
display_manager	string	auto-detected	Override DM: gdm, sddm, plasma-login-manager, greetd, or ly
autologin	bool | string	false	false to disable, or a username from system.users to auto-login that user
session	string	auto-from-environment	Session to autologin into; overrides the per-environment default (sddm .desktop basename / greetd command)
groups	list	[]	Opt-in package groups installed on top of the base set (keys of desktop_package_groups, e.g. dev)

All desktop environments are Wayland-only. sway and hyprland are available on Arch only; gnome and kde are available on all three families. On enterprise Linux (almalinux/rocky/rhel) the base desktop installs browser, PDF and image viewers but no video player - none is packaged in the EL base repositories, and no third-party repo is pulled in; add one from rpmfusion/flatpak if you need it.

When enabled: true, the bootstrap installs the desktop environment packages, enables the display manager and bluetooth services, and sets the systemd default target to graphical.target.

Display manager auto-detection: gnome to gdm; kde to plasma-login-manager on Arch and Fedora 44+ (Plasma 6.6), else sddm; sway and hyprland to greetd.

ly is an explicit-only override (never auto-selected), available on Arch only, and is desktop-agnostic - it can front any environment. It runs on tty2 with getty@tty2 masked, and its autologin is written to /etc/ly/config.ini; set session to the target session's .desktop basename (sway and hyprland resolve automatically).

When autologin names a user, the matching display manager is configured to log that user in without a password prompt. session is resolved automatically per environment when left empty (gdm picks its default, sddm uses plasma.desktop for kde, greetd runs the compositor command for sway/hyprland), so it only needs setting to override that choice.

4.2.6 system.features.firmware

Key	Type	Default	Description
enabled	bool | auto	auto	Install vendor firmware blobs. auto = on for physical, off for virtual
microcode	bool | auto	auto	Install CPU microcode. auto follows firmware.enabled

Defaults are designed so a baremetal install picks up firmware automatically with no inventory entry needed, while VMs skip it (the hypervisor handles those). The environment role detects CPU/GPU/wireless vendors from the live host (via lscpu and lspci) and the bootstrap role installs only the matching firmware packages. On Arch, this uses the vendor splits (linux-firmware-amdgpu, linux-firmware-realtek, etc.) so the install stays minimal. On Debian, it uses the equivalent firmware-* packages. Distros without firmware splits fall back to a single meta package.

4.2.7 system.features.gpu

Key	Type	Default	Description
enabled	bool	false	Install Mesa, Vulkan, and per-GPU userspace
nvidia_driver	string	auto	One of auto, open, proprietary, nouveau

Pair with desktop.enabled: true for a working desktop. The package set is determined by the same hardware profile as firmware. The nvidia_driver: auto default picks open (nvidia-open kernel modules) for Turing or newer GPUs, falls back to proprietary for older cards on distros that ship the proprietary driver, and falls back to nouveau elsewhere. Force a specific flavor by setting the value explicitly.

Proprietary and open Nvidia drivers on Fedora require RPMFusion non-free, which the bootstrap enables automatically when needed. Debian uses nvidia-driver from the non-free component (already enabled in the managed sources.list). Ubuntu uses restricted. Arch ships both nvidia-open-dkms and nvidia-dkms in the extra repository - no third-party setup required.

4.2.8 system.features.peripherals

Key	Type	Default	Description
enabled	bool | auto	auto	Master switch. auto follows desktop.enabled
fingerprint	bool | auto	auto	fprintd/libfprint. auto = install when reader detected
webcam	bool | auto	auto	v4l-utils and userspace tooling. auto follows enabled
displaylink	bool	false	DisplayLink dock support (explicit opt-in; see notes)

Fingerprint detection scans lsusb for known reader vendor IDs (Synaptics, Validity, Goodix, Elan, Egis, Broadcom, AuthenTec, Upek, Futronic). When fingerprint: auto and a reader is present, fprintd and the PAM helper are installed. PAM enrollment must be done post-install (fprintd-enroll).

DisplayLink ships proprietary userspace that distros do not package consistently. The bootstrap installs the in-tree evdi-dkms kernel module on Debian/Ubuntu and the evdi module on Fedora, but the userspace blob must still be installed manually from DisplayLink's site after first boot. Arch users typically use AUR (displaylink); this is not wired into the bootstrap.

4.2.9 system.features.hardware

Key	Type	Default	Description
profile	dict	{}	Hardware-detection override; empty means autodetect from live host

When empty, hardware is detected at the start of the bootstrap. When set, detection is skipped and the supplied profile drives package selection - this is the golden-image flow: bake an image with a fixed profile, snapshot it, and reuse the same profile on every deploy of that hardware class.

Profile shape:

system:
  features:
    hardware:
      profile:
        cpu: intel                    # intel | amd
        gpus: [intel, nvidia]         # any of: intel, amd, nvidia
        nvidia_supports_open: true    # set false to force proprietary/nouveau
        wireless: [intel]             # any of: intel, amd, atheros, broadcom,
                                      # mediatek, marvell, realtek, qcom, cirrus
        fingerprint: false            # set true to force fprintd install

4.3 hypervisor Dictionary

Key	Type	Default	Description
type	string	--	libvirt, proxmox, vmware, xen, or none
url	string	--	API host (Proxmox/VMware)
username	string	--	API username
password	string	--	API password
node	string	--	Target compute node (Proxmox node / VMware ESXi host; mutually exclusive with cluster on VMware)
storage	string	--	Storage identifier (Proxmox/VMware)
datacenter	string	--	VMware datacenter
cluster	string	--	VMware cluster
certs	bool	false	TLS certificate validation (VMware)
ssh	bool	false	Enable SSH on guest and switch connection (VMware)

4.4 cis Dictionary

When system.features.cis.enabled: true, the CIS role applies hardening. All values have sensible defaults; override specific keys via the cis dict.

Key	Type	Default	Description
modules_blacklist	list	see below	Kernel modules to blacklist via modprobe
sysctl	dict	see below	Sysctl key/value pairs written to 10-cis.conf
sshd_options	list	see below	SSHD options applied via lineinfile
pwquality_minlen	int	14	Minimum password length
tmout	int	900	Shell timeout (seconds)
umask	string	077	Default umask in bashrc
umask_profile	string	027	Default umask in /etc/profile
faillock_deny	int	5	Failed login attempts before lockout
faillock_unlock_time	int	900	Lockout duration (seconds)
password_remember	int	5	Password history depth

Default modules blacklist: freevxfs, jffs2, hfs, hfsplus, cramfs, udf, usb-storage, dccp, sctp, rds, tipc, firewire-core, firewire-sbp2, thunderbolt. squashfs is added automatically except on Ubuntu (snap dependency).

Default sysctl settings include: kernel.yama.ptrace_scope=2, kernel.kptr_restrict=2, kernel.perf_event_paranoid=3, kernel.unprivileged_bpf_disabled=1, IPv4/IPv6 hardening, ARP protection, and IPv6 disabled by default. Override individual keys:

cis:
  sysctl:
    net.ipv6.conf.all.disable_ipv6: 0    # re-enable IPv6
    net.ipv4.ip_forward: 1               # enable for routers/containers

Default SSHD options enforce: PermitRootLogin no, PasswordAuthentication no, X11Forwarding no, AllowTcpForwarding no, MaxAuthTries 4, and post-quantum KEX (mlkem768x25519-sha256 on OpenSSH 9.9+). Override per-option:

cis:
  sshd_options:
    - { option: X11Forwarding, value: "yes" }
    - { option: AllowTcpForwarding, value: "yes" }

Note: providing sshd_options replaces the entire list. Copy the defaults from roles/cis/defaults/main.yml and modify as needed.

4.5 VMware Guest Operations

When hypervisor.type: vmware uses the vmware_tools connection:

Variable	Description
ansible_vmware_tools_user	Guest OS username
ansible_vmware_tools_password	Guest OS password
ansible_vmware_guest_path	VM inventory path
ansible_vmware_host	vCenter/ESXi hostname
ansible_vmware_user	vCenter/ESXi API username
ansible_vmware_password	vCenter/ESXi API password
ansible_vmware_validate_certs	TLS certificate validation

4.6 Multi-Disk Schema

system.disks[0] is the OS disk (no mount.path). Additional entries define data disks.

Key	Type	Description
size	number	Disk size in GB (required for virtual)
device	string	Block device path (required for physical data disks)
partition	string	Derived from device during normalization (not user input)
mount.path	string	Mount point (additional disks only)
mount.fstype	string	btrfs, ext4, or xfs
mount.label	string	Filesystem label
mount.opts	string	Mount options (default: defaults)

system:
  disks:
    - size: 80                    # OS disk
    - size: 200                   # Data disk
      mount:
        path: /data
        fstype: xfs
        label: DATA

4.7 Advanced Partitioning Overrides

Variable	Default	Description
partitioning_efi_size_mib	512	EFI system partition size in MiB
partitioning_boot_size_mib	1024	Separate /boot size in MiB
partitioning_separate_boot	auto-derived	Force a separate /boot partition
partitioning_boot_fs_fstype	auto-derived	Filesystem for /boot
partitioning_use_full_disk	true	Use remaining VG space for root LV

Swap sizing: RAM >= 16GB gets swap = RAM/2. RAM < 16GB gets swap = max(RAM_GB, 2GB). Further capped to prevent over-allocation on small disks.

LVM layout (when not using btrfs): root, swap, and when CIS is enabled: /home (2-20GB, 10% of disk), /var (2GB), /var/log (2GB), /var/log/audit (1.5GB).

4.8 Cleanup Defaults

Post-install verification and recovery settings.

Variable	Default	Description
cleanup_verify_boot	true	Check VM accessibility after reboot
cleanup_boot_timeout	300	Timeout in seconds for boot verification
cleanup_remove_on_failure	true	Auto-remove VMs that fail to boot (created this run only)

5. Execution Pipeline

Roles execute in this order:

1. global_defaults -- normalize inputs, validate, set OS flags
2. system_check -- detect installer environment, verify live/non-prod target
3. virtualization -- create VM (if virtual), attach disks, cloud-init
4. environment -- prepare installer: mount ISO, configure repos, setup pacman, detect hardware
5. partitioning -- create partitions, LVM, LUKS, mount filesystems
6. bootstrap -- install base system, packages, and vendor-matched hardware bits
7. configuration -- users, fstab, locales, bootloader, encryption enrollment, networking
8. cis -- CIS hardening (when system.features.cis.enabled: true)
9. cleanup -- unmount, shutdown installer, remove media, verify boot

6. Usage

ansible-playbook -i inventory.yml main.yml
ansible-playbook -i inventory.yml main.yml -e @vars.yml

All credentials (system.users, system.root.password) must be defined in inventory or passed via -e.

Example inventory files are included:

• inventory_example.yml -- Proxmox virtual setup
• inventory_libvirt_example.yml -- libvirt virtual setup
• inventory_baremetal_example.yml -- bare-metal physical setup

7. Security

Use Ansible Vault for all sensitive values (hypervisor.password, system.luks.passphrase, user passwords in system.users, system.root.password).

8. Safety

The playbook aborts on non-live/production targets. It refuses to touch pre-existing VMs and only cleans up VMs created in the current run.