The Hardware Monitoring Daemon
In modern Ubuntu systems, the systemd-udevd service is a crucial background daemon. Its primary job is to listen for kernel events related to hardware devices (like plugging in a USB drive, connecting a monitor, or adding a new network card) and automatically execute scripts to configure them. It is what makes “plug-and-play” hardware work seamlessly on Linux desktop environments.
However, if you are running a strictly headless virtual machine (VM) in the cloud or a bare-metal server where the hardware configuration is absolutely static, udevd is largely unnecessary after the initial boot sequence. The hardware isn’t changing; no one is plugging USB drives into your Amazon EC2 instance. While disabling udevd entirely can cause issues with dynamic network interfaces on boot, stopping it on a running, static server can free up a tiny amount of memory and reduce background polling.
How to Stop the Udevd Service
You can halt the hardware polling daemon using systemctl.
Warning: Do not disable this on a desktop PC, a laptop, or any machine where you plug in external devices. Stopping this service will prevent new hardware from being recognized.
- Open your Ubuntu Terminal or connect via SSH.
- Stop the currently running service:
sudo systemctl stop systemd-udevd.service- If you want to prevent it from running on boot (not recommended for most setups, as it handles initial disk mounting), you can disable it:
sudo systemctl disable systemd-udevd.serviceThe daemon will cease listening for hardware events. Your server will continue running on its currently configured hardware, but any new hardware added to the system will require manual configuration and mounting.