New builds blocked by Quiet Start after restart

Last Reviewed:2025-09-22()
2 minute readKnowledge base

Issue

After a planned restart, users are unable to trigger new pipeline builds. A red banner is also displayed across all pages that reads The Jenkins Controller is preparing for shutdown. No new builds can be started:

Red banner shown on all pages

In the pipeline Builds widget, pending builds show a note that reads Jenkins is about to shut down:

Build widget showing

Cause

The controller was restarted with the Quiet start feature enabled. This feature intentionally keeps CloudBees CI in the quieting down state after a restart so that no new builds begin until an administrator explicitly cancels this state. This is typically used during maintenance to prevent build storms and allow controlled validation after startup.

Quiet Start is enabled from the UI: select the icon in the upper‑right corner Manage Jenkins  Quiet Restart and enabling the Stay in "quieting down" state when restarted option. If left enabled after maintenance, the controller restarts and remains in quiet mode, which blocks new builds.

Resolution

Cancel the quieting state (requires administrator permissions). You have two equivalent options:

  1. From the Build Queue widget, click the (cancel) link shown in the banner text: Jenkins is going to shut down. No further builds will be performed. (cancel)

    Cancel quiet mode
  2. Browse directly to the following endpoint (replacing <CONTROLLER_URL> with the affected controller’s URL):

    <CONTROLLER_URL>/cancelQuietDown

After cancelling, confirm that the red banner disappears and that new builds can be triggered.

To prevent recurrence after future restarts, select the icon in the upper‑right corner Manage Jenkins  Quiet Restart and uncheck Stay in "quieting down" state when restarted once maintenance is complete. This ensures the next restart behaves normally.

This article is part of our Knowledge Base and is provided for guidance-based purposes only. The solutions or workarounds described here are not officially supported by CloudBees and may not be applicable in all environments. Use at your own discretion, and test changes in a safe environment before applying them to production systems.