Service Upgrades¶
The LimaCharlie endpoint agent consists of two components that are versioned independently:
- On-disk agent — the service binary installed on the host. It handles core identity, cryptography, and transport. This component rarely changes and is what gets replaced during a service upgrade.
- Over-the-air core — the main functional component that delivers detection and response capabilities. It is downloaded from the LimaCharlie cloud and updated frequently. See Versioning & Upgrades for managing over-the-air updates.
The procedures on this page upgrade the on-disk agent only. This is useful when a new service binary is needed for bug fixes, platform compatibility, or to gain support for new on-disk features. Over-the-air core updates happen separately through the LimaCharlie cloud and do not require a service upgrade.
The upgrade process stops the running service, replaces the binary with the new version, and restarts the service. If the new version fails to start, an automatic rollback to the previous version occurs.
!!! note "Prerequisites" - The command must be run with root (Linux/macOS) or Administrator (Windows) privileges. - No installation key is required for upgrades.
Upgrade to Latest Version¶
Upgrade or Downgrade to a Specific Version¶
The --version flag can be used to move to any available sensor version, whether newer or older than the currently installed version. This is useful for rolling back to a known-good version or pinning to a specific release.
Note
The --version flag requires sensor version 4.33.28 or later.
Upgrade Using a Downloaded Sensor Binary¶
If you have already downloaded a sensor binary, you can upgrade the installed service directly by running it with the -u flag. This performs the same in-place upgrade without needing the shell installer.
Note
The -u flag requires sensor version 4.33.28 or later.
Advanced: Forcing an Upgrade¶
By default an in-place upgrade (-u) only replaces the installed service when the supplied binary is newer than what is installed. To re-apply or move to a build that is not strictly newer (for example to re-deploy a known-good version), set the LC_UPGRADE_SKIP_VERSION_CHECK environment variable to 1 (or true) on the upgrade process. This bypasses the version comparison and replaces the installed service unconditionally.
Warning
Use this only when you intend to override the version check. The automatic rollback on a failed start still applies, but skipping the check makes it possible to deliberately downgrade the on-disk agent.