2026.10.4
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Logs on Home Assistant OS

On Home Assistant Operating SystemHome Assistant OS, the Home Assistant Operating System, is an embedded, minimalistic, operating system designed to run the Home Assistant ecosystem on single board computers (like the Raspberry Pi) or Virtual Machines. It includes Home Assistant Core, the Home Assistant Supervisor, and supports apps. Home Assistant Supervisor keeps it up to date, removing the need for you to manage an operating system. Home Assistant Operating System is the recommended installation type for most users., other parts of the system have their own logs, for example, the Supervisor and each of your apps. The logs of earlier startups of the system are kept as well. You view all of them on the Logs page.

For the logs that every installation has, such as viewing and downloading the Home Assistant log, refer to Viewing and downloading logs.

Viewing the logs of other parts of the system

Besides the Home Assistant log, the Logs page shows the logs of the other parts of the system.

Prerequisites

  • Administrator rights.
  • Home Assistant Operating SystemHome Assistant OS, the Home Assistant Operating System, is an embedded, minimalistic, operating system designed to run the Home Assistant ecosystem on single board computers (like the Raspberry Pi) or Virtual Machines. It includes Home Assistant Core, the Home Assistant Supervisor, and supports apps. Home Assistant Supervisor keeps it up to date, removing the need for you to manage an operating system. Home Assistant Operating System is the recommended installation type for most users..

To view the logs of other parts of the system

  1. Go to Settings > System > Logs.
  2. In the top-right corner, select the button with the name of the log that is shown, for example, Home Assistant Core.
  3. Select the log that you want to see.
    • Result: The log is shown. New messages are added at the bottom while the page is open.
    • To download this log, refer to Downloading the logs.

The following logs are available:

  • Home Assistant Core: Home Assistant itself, including your integrations, automations, and scripts.
  • Supervisor: The part of the system that manages updates, backups, and apps.
  • Host: The operating system.
  • DNS, Audio, and Multicast: The services for name resolution, sound, and device discovery on your network.
  • Your apps, by name.

Viewing the logs of an earlier startup

The logs of earlier startups of the system are kept until the space for logs is full. Then the oldest logs are removed. For example, if the system rebooted because of a problem, the log of the previous startup can show what happened before the reboot.

A startup is a start of the entire system, for example, after a reboot. Restarting Home Assistant doesn’t count as a startup. After a long time without a reboot, only the current startup may be left. Then Show HAOS startups isn’t shown in the menu.

Prerequisites

  • Administrator rights.
  • Home Assistant Operating SystemHome Assistant OS, the Home Assistant Operating System, is an embedded, minimalistic, operating system designed to run the Home Assistant ecosystem on single board computers (like the Raspberry Pi) or Virtual Machines. It includes Home Assistant Core, the Home Assistant Supervisor, and supports apps. Home Assistant Supervisor keeps it up to date, removing the need for you to manage an operating system. Home Assistant Operating System is the recommended installation type for most users..
  • The logs of an earlier startup are still kept.

To view the logs of an earlier startup

  1. Go to Settings > System > Logs.
  2. Select the log that you want to see.
  3. Select Menu > Show HAOS startups.
  4. In the list of startups, select the startup.
    • Current is the log since the last startup. Previous is the startup before that. Earlier startups are shown as, for example, 2 startups ago.
    • Result: The log of that startup is shown.

To download the log of an earlier startup, first show it as described above. Then follow the steps in Downloading the logs.

Writing the Home Assistant log to a file

On Home Assistant Operating SystemHome Assistant OS, the Home Assistant Operating System, is an embedded, minimalistic, operating system designed to run the Home Assistant ecosystem on single board computers (like the Raspberry Pi) or Virtual Machines. It includes Home Assistant Core, the Home Assistant Supervisor, and supports apps. Home Assistant Supervisor keeps it up to date, removing the need for you to manage an operating system. Home Assistant Operating System is the recommended installation type for most users., Home Assistant writes its log to the system journal, not to a file. If you need the log as a file, for example, for a tool that reads it, you can also write it to home-assistant.log in your configuration folder. This setting is called the duplicate log file.

Prerequisites

  • Administrator rights.
  • Home Assistant Operating SystemHome Assistant OS, the Home Assistant Operating System, is an embedded, minimalistic, operating system designed to run the Home Assistant ecosystem on single board computers (like the Raspberry Pi) or Virtual Machines. It includes Home Assistant Core, the Home Assistant Supervisor, and supports apps. Home Assistant Supervisor keeps it up to date, removing the need for you to manage an operating system. Home Assistant Operating System is the recommended installation type for most users..
  • Access to the command line. For details, refer to Home Assistant via the command line.

To write the Home Assistant log to a file

  1. On the command line, enter the following commands:

    ha core options --duplicate-log-file=true
ha core rebuild
    • Result: Home Assistant restarts and writes its log to home-assistant.log in your configuration folder as well.

To stop writing the log to a file, enter the same commands with false:

ha core options --duplicate-log-file=false
ha core rebuild

Where the logs are stored

All logs are stored in the system journal of the operating system. They are kept across startups, until the space for logs is full. You view them on the Logs page, or with the ha command, for example, ha core logs or ha supervisor logs.

If a home-assistant.log file is left in your configuration folder, Home Assistant renames it to home-assistant.log.old when it starts. This doesn’t happen when you write the log to a file.