cloud-init

Display the status of the most recent cloud-init run

$ cloud-init status

$ cloud-init status --wait

$ cloud-init query --list-keys

$ cloud-init query [dot_delimited_variable_path]

$ cloud-init clean

cloud-init [options...] subcommand [args...]
e.g., cloud-init init [--local] [--network]

--help, -h
    Show help message and exit

--version
    Show cloud-init version

--verbose, -v
    Increase verbosity (repeat for more)

--debug, -d
    Enable debug logging

--quiet, -q
    Reduce logging verbosity

--file FILE, -f FILE
    Read configuration from FILE

--frequency FREQ
    De-duplication frequency (e.g., 'once', 'always')

--force
    Force execution regardless of cache

--log-dir LOG_DIR
    Use custom log directory

--log-file LOG_FILE
    Log to specific file

--no-cache
    Disable cache usage

--local
    Run local stage only (early boot)

cloud-init is the industry-standard tool for initializing cloud instances across distributions like Ubuntu, CentOS, Debian, and RHEL. It runs during the first boot to apply user-provided configuration data fetched from metadata services (e.g., AWS EC2, Azure, OpenStack, GCP).

It processes YAML-formatted cloud-config data through three main stages: init (early boot, networking), config (per-boot, hostname, users, packages), and final (late boot, services). Modules handle tasks like resizing filesystems, managing SSH keys, installing snaps/packages, writing files, and running scripts.

cloud-init supports datasource plugins for cloud detection and is idempotent, ensuring safe re-runs. Logs are in /var/log/cloud-init*. It's essential for IaC tools like Terraform and Packer, enabling reproducible environments without manual post-boot intervention.

Requires cloud metadata services; may fail on non-cloud VMs. Not for repeated runs without --force. Logs can grow large; use cloud-init clean to reset.

init: Run init stage.
modules: List/analyze modules.
status: Check status.
clean: Reset state.
collect-logs: Gather logs.

Data from NoCloud, ConfigDrive, EC2, OpenStack, etc. See /etc/cloud/cloud.cfg.d/.

Developed in 2008 by Scott Moser at Canonical for Ubuntu cloud images. Evolved for MAAS, OpenStack; upstreamed in 2014. Now maintained by Canonical, supports 20+ distros, version 24.2+ as of 2024.

cloud-init status(7), ds-identify(8), cloud-config(5), growpart(8), curtin(7)