How to Completely Disable the ‘zfs-zed’ (ZFS Event Daemon) in Ubuntu Server

The zfs-zed (ZFS Event Daemon) is a background service in Ubuntu Server that monitors the health and state of ZFS storage pools. It listens for kernel events generated by the ZFS module and can trigger automated scripts—such as sending an email alert when a drive fails or initiating a scrub. While absolutely critical for production file servers utilizing the ZFS file system (like those running TrueNAS or dedicated LXD hosts), it is completely useless if your Ubuntu Server uses standard Ext4, XFS, or Btrfs partitions. If ZFS is not in use, leaving zfs-zed running wastes RAM and adds unnecessary noise to system logs as it initializes.

This guide explains how to completely disable the zfs-zed daemon in Ubuntu Server.

Stop and Disable the ZFS Event Daemon

To ensure the server does not waste resources monitoring for ZFS events that will never occur, we must halt the daemon and explicitly mask it via systemd.

1. Log into your Ubuntu Server via SSH or local console using an account with sudo privileges.
2. First, stop the active service to immediately halt its monitoring loop:

   sudo systemctl stop zfs-zed.service

3. Next, disable the service so it does not attempt to start during the next boot sequence:

   sudo systemctl disable zfs-zed.service

4. To guarantee that no other dependent ZFS utility (if any are accidentally invoked) can wake the daemon, mask the service unit entirely:

   sudo systemctl mask zfs-zed.service

Verify the Daemon Isolation

By masking the service, you guarantee that the ZFS event monitoring subsystem is entirely inert, freeing up a small amount of memory and CPU cycles.

To verify the lockdown is successful, run the following command to check the status of the daemon:

systemctl status zfs-zed.service

The output will clearly state that the service is masked (symlinked to /dev/null) and the Active state will read inactive (dead). If you run ps aux | grep zed, you will confirm that the daemon process is no longer running in the background, confirming that your standard Ubuntu Server is completely free from unnecessary ZFS overhead.