In Ubuntu Server and other modern Linux distributions, systemd-boot-check-no-failures.service is a specialized systemd unit designed to verify the integrity of the boot process before allowing certain subsequent actions to occur. When enabled, this service explicitly checks if any other systemd units have entered a “failed” state during startup. If failures are detected, it exits with an error code, effectively signaling a broken boot. While useful in automated fallback architectures (such as A/B partition updates) to trigger a rollback if a critical service crashes, it can become a significant operational liability in highly customized, strict, or development server environments. In these scenarios, administrators may intentionally allow non-critical services to fail (e.g., a hardware probe on a VM, or a secondary network interface waiting for configuration) without wanting the entire boot validation process to halt or trigger upstream alerting.
This guide explains how to completely disable the systemd-boot-check-no-failures service in Ubuntu Server, ensuring that boot state validation is strictly managed by administrators rather than automated dependency checks.
Stop and Mask the systemd-boot-check-no-failures Service
Because this service is tightly integrated into the boot sequence and often pulled in as a dependency by other targets (like boot-complete.target), a simple disable command is often insufficient. To guarantee the init system is physically prevented from executing the failure check logic under any circumstances, we must explicitly mask the unit file.
- Log into your Ubuntu Server via SSH using an account with
sudoprivileges. - Check the current status of the service:
sudo systemctl status systemd-boot-check-no-failures.service - Disable the service to remove it from the systemd boot targets:
sudo systemctl disable systemd-boot-check-no-failures.service - For absolute certainty, explicitly mask the unit. This symlinks the unit file to
/dev/null, creating a hard cryptographic block against it being invoked by systemd during the startup sequence or by any upstream targets:sudo systemctl mask systemd-boot-check-no-failures.service
Verify the Service Lockdown
By masking systemd-boot-check-no-failures.service, you guarantee that systemd will bypass the global failure check, allowing the system to proceed to its final runlevel or target regardless of isolated unit crashes.
To verify the lockdown is successful, attempt to start the service manually:
sudo systemctl start systemd-boot-check-no-failures.serviceSystemd will return a fatal error stating that the unit is masked (e.g., Failed to start systemd-boot-check-no-failures.service: Unit systemd-boot-check-no-failures.service is masked). You have successfully neutralized the automated boot failure verification mechanism, asserting total administrative control over the server’s boot logic and error handling.