Before installation: hardware and HAOS

Why you need your own host

You may already have explored the rest of this guide, only to reach a practical question: Where does Home Assistant actually run?

Home Assistant is neither a mobile app nor a website account. It is software that runs on a computer in your home, stays on around the clock, connects to your router, and communicates with your lights and sensors. Keeping the data at home is a major reason people choose it—but first, you need that computer.

The host can be a palm-sized Raspberry Pi, an official Home Assistant appliance, a used mini PC, or even a virtual machine on a NAS. This appendix compares the options and then guides you through installation.

By the end of this appendix, you will be able to:

• Distinguish the four installation methods and choose the right one for a new installation—HAOS in most cases.
• Select a host that suits the size of your home and your budget.
• Write the system image to an SD card or SSD and boot the host.
• Complete onboarding, create the Owner account, and set your home's location.
• Diagnose common problems, including a host that cannot be found, a system that will not boot, or unexpected restarts.

Four installation methods: new users should choose HAOS

Online guides mention four installation methods, which can be confusing. The short answer is: for your first installation, choose Home Assistant Operating System (HAOS).

Home Assistant now recommends only two methods: HAOS and Container. In May 2025, the project deprecated Core and Supervised. Warnings began with version 2025.6, and support ended with version 2025.12. Support also ended for the 32-bit i386, armhf, and armv7 architectures. The official migration path is from Core to Container, and from Supervised to HAOS.

Choosing hardware: the main options compared

Home Assistant itself has modest performance requirements. For a typical home with 30–50 devices, a quad-core ARM processor and 4GB of memory provide ample capacity. What places real demands on the host is what you add later: camera recording and image recognition, local voice processing, and an ever-growing history database. Hardware that is sufficient today may not suit your plans two years from now.

Current official hardware

Home Assistant Green is the official model currently promoted for sale. It uses a Rockchip RK3566 with four ARM Cortex-A55 cores at 1.8GHz, 4GB of memory, 32GB of eMMC storage, and a microSD slot for recovery. Connections include Gigabit Ethernet, two USB 2.0 ports, and an HDMI port for diagnostics. An aluminium heat sink provides fanless passive cooling. The package includes a Gigabit Ethernet cable and a 12V / 1A universal power supply with EU, US, and UK plug adapters; use the adapter that matches sockets in your region. The official list price is US$199 / €179, but local prices vary considerably. Check the price and package contents offered by your regional retailer.

One Green specification deserves attention: its two USB 2.0 ports can supply up to 5V 2A in total. Before connecting a bus-powered USB storage drive, confirm that its power requirements fit within this limit. A low-power device such as a Zigbee radio is normally not a concern.

Home Assistant Yellow is discontinued. It is no longer manufactured, although existing units continue to receive software updates; Home Assistant directs new buyers to Green instead. For existing owners, Yellow is based on a Raspberry Pi Compute Module 4, includes an M.2 M-Key slot for 2230 / 2242 / 2260 / 2280 NVMe SSDs, and has a Silicon Labs MGM210P radio supporting Zigbee 3.0, OpenThread, and Matter. Its integrated radio remains useful in an existing installation, but Yellow is not a current-hardware recommendation.

The ODROID family is another existing option; the official installation documentation covers N2, N2+, C2, C4, M1, and M1S models, which follow a Pi-like approach but use eMMC modules. Note that the M1 documentation explicitly states that booting from NVMe is not supported. For the N2+ and M1S, you connect the board directly to another computer with a USB-OTG cable so that it appears as a storage device, then write the image to it. This process differs from the Pi procedure and is best suited to people who already own compatible hardware.

Storage media: SD cards are a common point of failure

This may be the most valuable section in the appendix. When a Home Assistant host fails, the cause is often not the main board but a worn-out SD card.

Why SD cards fail

Each block of flash memory in an SD card can be written only a finite number of times. A card used for photography may record a few hundred files a day and last for years. Home Assistant creates a very different workload:

• The database is written constantly. Recorder stores every sensor-value change and every light being switched on or off. With temperature and humidity sensors, writes can occur every minute.
• System logs are written constantly. Integration errors, device disconnections, and reconnection attempts all leave records.
• The host runs 24 hours a day. Each day's writes are repeated 365 days a year.

After six months to a year, some users find that the dashboard no longer loads, the host does not respond, and a restart does not recover it—the SD card has become read-only or developed irrecoverable errors. Worse, failure can be gradual: the dashboard first becomes sluggish, automations occasionally fail to trigger, or updates stop midway. These symptoms resemble software faults, so the storage medium is easy to overlook.

What should you use?

How much capacity do you need? The operating system and a typical household database can fit within 32GB, but retained backups, several Apps, or camera clips soon consume the remaining space. For a system you assemble yourself, choose at least 128GB. The modest additional cost avoids a more difficult migration later.

Already using an SD card?

HAOS includes a “Move data disk” function that transfers data to another connected storage device. The system continues to boot from the original medium, while subsequent data reads and writes use the new drive. Go to Settings > System > Storage and select “Move data disk.”

Pre-installation checklist

Check this list before placing an order. A single missing item can stop the installation halfway through.

Install HAOS and start the host

The following procedure uses the most common case, a Raspberry Pi. Home Assistant recommends Raspberry Pi Imager, available from raspberrypi.com/software, because it downloads the correct image for you. If you prefer to download an image manually, you can write it with balenaEtcher.

1. Install the imaging tool on another computer

   Download and install Raspberry Pi Imager from raspberrypi.com/software. Perform this step on your everyday computer, not on the Pi—the Pi does not yet have an operating system.

2. Connect the SD card or SSD to the computer

   Connect it with a card reader or suitable adapter. If the operating system asks whether to format the device, select Cancel; the imaging tool will format it correctly.

3. Select the operating system in Imager

   Open Raspberry Pi Imager, select the operating-system menu, and go to Other specific-purpose OS > Home automation > Home Assistant. Select the image for your exact model: choose the RPi 4 image for a Raspberry Pi 4, or the RPi 5 image for a Raspberry Pi 5. An image for the wrong model may be written successfully but will not boot. This is a common installation mistake.

4. Select the destination and write the image

   Select your SD card or SSD and verify its capacity so that you do not accidentally choose another external drive. Select “Next,” then “Write.” This step will erase the entire destination device and usually takes several minutes. When it finishes, select “Finish” and safely eject the device.

5. Install the medium, connect Ethernet, and apply power

   Return the newly written medium to the host. Connect the Ethernet cable before the power supply. The first boot requires internet access because the system downloads current components. You do not need a monitor or keyboard. If you do connect a monitor, scrolling text is normal and does not require action.

6. Wait, then connect in a browser

   From a computer or phone on the same network, open homeassistant.local. The official documentation says a Pi 4 or Pi 5 will usually become available within one minute. If it does not respond, try homeassistant.local:8123; if that also fails, use the host's IP address followed by :8123. “Preparing Home Assistant” means that the latest version is downloading. The documentation gives no fixed duration because preparation time depends on the hardware and internet connection; ten to twenty minutes is common in practice, and an SD card may take longer. Do not disconnect power during this process.

Mini PCs and old laptops (x86-64)

The procedure differs because you must first configure the BIOS. The official requirements are a 64-bit-capable machine and UEFI boot. Enter the BIOS—usually by pressing F2, Del, F1, or F10 during startup, depending on the manufacturer—set the boot mode to UEFI, disable Secure Boot, save the changes, and exit.

The image is named haos_generic-x86-64-Version.img.xz. The recommended method is to boot Ubuntu from a USB drive, then use Ubuntu's built-in Disks utility to restore the image to the target drive. Alternatively, use balenaEtcher on another computer to write the target medium, then install that medium in the host. Finally, connect Ethernet, start the machine, and open homeassistant.local.

Virtual machines and NAS systems

Home Assistant provides disk images for several platforms: .vdi for VirtualBox, .qcow2 for KVM or Proxmox, and .ova for VMware ESXi or vSphere. The documentation also covers Unraid. The official minimum allocation is 2GB of memory and 2 vCPUs; increase these resources if your workload requires more.

First-time onboarding: create the Owner account

When “Preparing Home Assistant” finishes, the welcome page appears. Home Assistant calls this process onboarding. You complete it entirely in the browser; no command-line work is required.

1. Choose “Create my smart home” or restore a backup

   For a new installation, select Create my smart home. If you are replacing a host and have a backup from the old system, restore it here instead. This recovery path is one reason to read Chapter 9 early.

2. Enter your name, username, and password

   The official documentation states that the account created during initial setup becomes the Owner. The Owner is always an administrator and has full control of the system, including the ability to create other accounts. The username must be lowercase and contain no spaces.

   Choose a strong password and store it safely. This system may know when your home is empty. If you forget the Owner password, the official recovery process requires placing the system back into an onboarding state. There is no simple emailed “forgot password” link. See Chapter 5 for users and permissions.

3. Set your home's location

   Mark your home on the map. This sets the time zone, unit system, and currency, and creates a Home zone with a default radius of 100 metres. Presence-based automations, such as turning on a light when someone arrives, use this zone. Confirm that the selected IANA time zone matches your location. You can change these settings later as described in Chapter 2.

4. Choose whether to share analytics

   This page asks whether you want to share anonymous usage statistics. The option is disabled by default, although Home Assistant encourages participation because the data helps the team prioritise device support. Your choice does not affect any features.

5. Select “Finish” and review what Home Assistant found

   Selecting “Finish” opens the dashboard. Home Assistant scans the local network for visible devices and may offer to configure several discoveries. Do not feel obliged to add everything immediately. Let the host run reliably for a day before expanding the installation.

Networking: use a wired connection

This recommendation is worth repeating: connect your Home Assistant host by Ethernet.

Wi-Fi can work, but an unreliable wireless connection can waste hours of troubleshooting. Imagine an automation that should turn on the living-room lights at 7:30 pm. Sometimes it runs tens of seconds late; sometimes it does not run at all. The automation, devices, and logs appear normal, but the host's Wi-Fi briefly disconnected. Because the symptoms do not resemble a network fault, the cause is particularly difficult to identify.

The final row matters. Zigbee and Thread use the 2.4GHz band, as does common Wi-Fi equipment. If the host uses 2.4GHz Wi-Fi beside a Zigbee radio, interference may cause sensors to disconnect intermittently. Moving the radio away from the host on a USB extension cable can make a real difference.

View or change the host's network settings and hostname under Settings > System > Network. The address homeassistant.local depends on mDNS (multicast DNS), which some routers and managed networks block. If that address does not resolve, connect by IP address instead; Home Assistant works in exactly the same way.

Power, cooling, and UPS protection

Power: do not substitute an arbitrary phone charger

Inadequate power is a classic source of Raspberry Pi problems. The host may restart at random while apparently idle, or become unstable after you connect a USB drive. These symptoms are easily mistaken for software, storage, or memory faults.

The Pi 5 deserves particular attention: it requires a 5A USB-C PD supply, a profile that ordinary phone chargers may not provide. A charger can have the same connector and an apparently adequate wattage yet still fail to power the Pi correctly, producing subtle symptoms. Use the official power supply; this is not a sensible place to economise.

Cooling: excess heat reduces performance

An overheating ARM processor protects itself by reducing its clock speed. The dashboard then becomes less responsive and updates take longer. A Raspberry Pi 4 or 5 can run hot inside a sealed plastic case, so use a ventilated metal case with a heat sink or add a small fan. Home Assistant Green uses a passive aluminium heat sink and needs no fan.

Placement also affects cooling. Do not put the host at the back of a closed media cabinet, stack it with a router or other warm equipment, or bury it under cables. Choose an accessible location with free airflow.

UPS: protection during an outage

Utility faults and construction work can interrupt power in any country. Abruptly cutting power while the host is writing creates the database-corruption risk described above. An inexpensive uninterruptible power supply (UPS) that runs for ten minutes or more is usually sufficient. The aim is not indefinite operation, but enough time to shut down cleanly or ride through a brief interruption.

Your first tasks after installation

Once the system is running, resist the urge to add many devices immediately. Complete these tasks in order to avoid trouble later.

1. Reserve the IP address on your router

   Create the DHCP reservation described in the network section. This is the only task performed outside Home Assistant, so complete it first.

2. Configure automatic backups and copy them off the host

   A backup stored only on the host's own drive will be lost with the drive, making it no backup at all. Chapter 9 explains how to schedule backups and send them to storage outside the host.

3. Check for updates and always back up before installing them

   Home Assistant Core is released approximately monthly; a version such as 2026.8 means the August 2026 release. HAOS has a separate, smaller version number; at the time of writing, both the documentation example and latest release use 18.2. Seeing “Core 2026.8” and “Operating System 18.2” together is therefore normal. Staying current is worthwhile, but always create a backup before updating.

4. Continue to Chapter 1

   The hardware introduction is complete. Continue with Chapter 1 to learn the interface, install the mobile app, configure time and location settings, establish naming rules, and build your first automation.

Common problems

1. The browser does not respond at homeassistant.local

   This is usually an mDNS problem, not a failed host. Try these steps in order: (1) Open homeassistant.local:8123; installations from before 2026.8 require the port number. (2) Open your router's administration page, find its list of connected devices, and look for a device named something like homeassistant. Copy its IP address and open http://thatIP:8123. (3) Confirm that your phone or computer is on the same network segment as the host. Guest Wi-Fi and separately named 2.4GHz or 5GHz networks may isolate clients from one another. (4) Managed workplace and education networks often block mDNS; use the IP address instead.

2. The image was written successfully, but the host shows no activity

   First, check for an image intended for the wrong model. A Raspberry Pi 4 image in a Pi 5, or vice versa, may fail to boot without a useful message; this is the most common cause. Next, write the card again in case the imaging tool or a low-quality card reader failed. Finally, connect an HDMI display: no signal usually points to boot media, while text that stops partway indicates a different fault. On an x86 machine, verify that the BIOS uses UEFI and that Secure Boot is disabled.

3. First startup remains on “Preparing Home Assistant” for a long time

   This page is normal while the system downloads the latest version. The official documentation says only that preparation may take some time; in practice, ten to twenty minutes is reasonable, and an SD card may be slower. Do not disconnect power during this stage. If it remains there for more than an hour, verify that Ethernet is connected, the router has assigned an IP address, and the internet connection works. This stage requires internet access.

4. The host restarts at random

   Suspect the power supply before the software. Common causes include running a Raspberry Pi 5 without the official 27W / 5A supply, powering a Pi 4 from a phone charger, or attaching a bus-powered USB drive. Test with the official supply for a week. Next, check for overheating: if the case is hot, add a heat sink or fan. Only then investigate failing storage.

5. After several months, the dashboard is sluggish and updates often fail

   These are classic signs of a failing SD card. Create a full backup immediately and download it to your own computer, then plan a move to an SSD. Use “Move data disk” under Settings > System > Storage, or install HAOS on new media and restore the backup. Do not delay: once the card fails completely, its data may be unrecoverable.

6. The “Add-ons” panel is missing after installation

   The panel was renamed. From version 2026.2, it is called Apps and appears under Settings > Apps. Also note that Container installations do not include this panel; the official documentation explicitly states that Apps are not available with Container. Of the currently supported installation methods, only HAOS includes Apps. Supervised also included them, but support ended in 2025.12, so it is for existing installations only.

FAQ