What is Acpid?
In Ubuntu, acpid (Advanced Configuration and Power Interface event daemon) is a background service designed to listen for hardware-level power events and translate them into software actions. For example, if you close the lid on your laptop, or press the physical power button on your PC case, acpid detects that hardware trigger and tells the operating system to initiate a suspend or shutdown sequence.
While critical for a desktop or laptop, acpid is often entirely unnecessary on a headless server. If your Ubuntu server is running in a virtual machine (VM) in the cloud, or sitting in a locked server rack where nobody will ever physically press the power button, running a background daemon constantly listening for lid-closures is a waste of CPU cycles. You can safely disable it.
How to Disable Acpid in Ubuntu
You can stop this power-event listener using the standard systemctl commands.
- Open your Ubuntu Terminal (or connect via SSH).
- First, stop the daemon from running in your current session:
sudo systemctl stop acpid.service- Next, disable the service so it does not launch automatically upon reboot:
sudo systemctl disable acpid.service- To ensure that absolutely no other power-management tool or dependent package can accidentally trigger the service to start, you should “mask” it. Masking completely disables the service configuration:
sudo systemctl mask acpid.service- Verify the daemon is no longer running by checking its status:
systemctl status acpid.serviceYour server will continue to handle software reboots (like typing sudo reboot) perfectly fine, but it will no longer waste resources listening for physical hardware buttons that no one will ever press.