Frequently Asked Questions

Tips for using ESPHome

  1. ESPHome supports (most of) Home Assistant’s YAML configuration directives like !include and !secret. So you can store all your secret WiFi passwords and so on in a file called secrets.yaml within the directory where the configuration file is.

    An enhancement to Home Assistant’s !include accepts a list of variables that can be substituted within the included file.

    binary_sensor:
  - platform: gpio
    id: button1
    pin: GPIOXX
    on_multi_click: !include { file: on-multi-click.yaml, vars: { id: 1 } } # inline syntax
  - platform: gpio
    id: button2
    pin: GPIOXX
    on_multi_click: !include
      # multi-line syntax
      file: on-multi-click.yaml
      vars:
        id: 2

    on-multi-click.yaml:

    - timing: !include click-single.yaml
  then:
    - mqtt.publish:
        topic: ${device_name}/button${id}/status
        payload: single
- timing: !include click-double.yaml
  then:
    - mqtt.publish:
        topic: ${device_name}/button${id}/status
        payload: double

    For even more configuration templating, take a look at Substitutions.

  2. If you want to see how ESPHome interprets your configuration, run

    esphome config livingroom.yaml

  3. To view the logs from your node without uploading, run

    esphome logs livingroom.yaml

  4. You can always find the source ESPHome generates under <NODE_NAME>/src/.

  5. You can view the full list of command line interface options here: Command Line Interface

  6. Use Substitutions to reduce repetition in your configuration files.

I can’t get flashing over USB to work

ESPHome depends on the operating system the tool is running on to recognize the ESP. This can sometimes fail. Common causes are that you may not have the drivers installed (see here) or you are trying to upload from a Docker container and did not mount the ESP device into your container using --device=/dev/ttyUSB0.

First, you need to get the firmware file to flash. For the Home Assistant add-on based installs you can use the Manual download method of the Dashboard (click Install in the overflow icon with the three dots and then select Manual download). For direct esphome command line based installs you can access the file under <CONFIG_DIR>/<NODE_NAME>/.pioenvs/<NODE_NAME>/firmware.bin.

Second, you need to put the ESP in programming mode while connecting it to your computer.

Third, to flash a firmware file downloaded from Home Assistant add-on Dashboard, you can use:

  • ESPHome Web web-based installer, which requires a browser that supports WebSerial, like Google Chrome or Microsoft Edge. Connect the board to your computer, make sure it’s detected as a serial port, and press Connect. Give the requested permission in the browser and in the pop-up box that appears, select the serial device which connects to your ESP. Then press Install, and browse for the binary file you downloaded from the Dashboard in the step above. Note that the file will be processed locally, it won’t be uploaded to any cloud service.

  • esptool from the GitHub repository, package from your distro or install it yourself with pip install esptool (in case of Linux).

Before using esptool, make sure you know which serial port your programming adapter is connected to. In Linux use the dmesg command afer you plug the device into the USB port to see the name of the newly detected serial port. In Windows check the Device Manager to see if a new serial port appears when you plug it in and note the COM number.

Erase flash:

esptool --port /dev/ttyUSB0 erase_flash

Program flash with your firmware binary:

esptool --port /dev/ttyUSB0 write_flash 0x0 your_node_firmware.bin

Note

If you’re just seeing Connecting....____.... on the screen and flashing fails:

  • verify that the device name of the port has not changed while you were re-plugging it too fast (eg. changed from /dev/ttyUSB0 to /dev/ttyUSB1).

  • double check the UART wires are connected correctly if flashing using an external programmer (RX of programmer to TX of the ESP and vice-versa).

  • for some devices you need to keep GPIO0 and GND connected at least until flashing has begun.

  • for some devices you need to power-cycle in programming mode after erasing flash, they don’t auto-reset.

  • it also might be a sign that ESP is defective, damaged or otherwise cannot be programmed.

If you’re in an RF noisy environment or your UART wires are a bit long, flashing can fail during transfer. Don’t worry, an ESP won’t brick just because of that. Put it again in programming mode and flash with a reduced baudrate for safer transfers:

esptool.py --port /dev/ttyUSB0 --baud 460800 write_flash 0x0 your_node_firmware.bin

Help! Something’s not working!!

That’s no good. Here are some steps that resolve some problems:

How to submit an issue report

First of all, thank you very much to everybody submitting issue reports! While we try to test ESPHome/YAML as much as we can using our available hardware, we don’t own every single device type and rely on testing done by the community and the contributors. When doing some changes in the core, it can quickly happen that something somewhere breaks. Issue reports are a great way for us to track and (hopefully) fix issues, so thank you!

For us to fix the issue quickly, there are some things that would be really helpful:

  1. Just writing “X doesn’t work” or “X gives bug” is not helpful!!! Seriously, how do you expect help given just that information?

  2. A snippet of the code/configuration file used is always great to reproduce this issue. Please read How to create a Minimal, Complete, and Verifiable example.

  3. If it’s an I²C or hardware communication issue please also try setting the log level to VERY_VERBOSE as it provides helpful information about what is going on.

  4. Please also include what you’ve already tried and didn’t work as that can help us track down the issue.

You can find the issue tracker here https://github.com/esphome/issues

How do I update to the latest version?

It’s simple. Run:

pip3 install -U esphome
# From docker:
docker pull ghcr.io/esphome/esphome:stable

And in Home Assistant, there’s a simple UPDATE button when there’s an update available as with all add-ons.

How do I update to the latest beta release?

ESPHome has a beta release cycle so that new releases can easily be tested before the changes are deployed to the stable channel. You can help test ESPHome (and use new features) by installing the tested beta:

# For pip-based installs
pip3 install --pre -U esphome

# For docker-based installs
docker run [...] -it ghcr.io/esphome/esphome:beta run livingroom.yaml

For Home Assistant supervised installs add the community addons beta repository by adding https://github.com/hassio-addons/repository-beta in Add-on store -> Repositories.

The beta docs are available at beta.esphome.io

How do I use the latest bleeding edge version?

First, a fair warning that the latest bleeding edge version is not always stable and might have issues. If you find some, please do however report them.

To install the dev version of ESPHome:

  • In Home Assistant: Add the ESPHome repository https://github.com/esphome/home-assistant-addon in Add-on store -> Repositories. Then install the add-on ESPHome Dev

  • From pip: Run pip3 install https://github.com/esphome/esphome/archive/dev.zip

  • From docker, use the ghcr.io/esphome/esphome:dev image

    docker run [...] -it ghcr.io/esphome/esphome:dev livingroom.yaml compile

The latest dev docs are here: next.esphome.io

How do I use my Home Assistant secrets.yaml?

If you want to keep all your secrets in one place, make a secrets.yaml file in the esphome directory with these contents (so it pulls in the contents of your main Home Assistant secrets.yaml file from one directory higher):

<<: !include ../secrets.yaml

Does ESPHome support [this device/feature]?

If it’s not in the docs, it’s probably not supported. However, we are always trying to add support for new features, so feel free to create a feature request in the ESPHome feature request tracker. Thanks!

I have a question… How can I contact you?

Sure! We are happy to help :) You can contact us here:

My node keeps reconnecting randomly

Jep, that’s a known issue. However, it seems to be very low-level and we don’t really know how to solve it. We are working on possible workarounds for the issue, but currently we do not have a real solution.

Some steps that can help with the issue:

  • If you’re using a hidden WiFi network, make sure to enable fast_connect mode in the WiFi configuration (also sometimes helps with non-hidden networks)

  • Give your ESP a static IP.

  • Set the power_save_mode to light in the wifi: config (only helps in some cases, in other it can make things worse). See Power Save Mode.

  • The issue seems to happen with cheap boards more frequently. Especially the “cheap” NodeMCU boards from eBay which sometimes have quite bad antennas.

  • ESPHome reboots on purpose when something is not going right, e.g. wifi connection cannot be made or api connection is lost or mqtt connection is lost. So if you are facing this problem you’ll need to explicitly set the reboot_timeout option to 0s on the components being used.

  • If you see Error: Disconnecting <NODE_NAME> in your logs, ESPHome is actively closing the native API client connection. Connect a serial console to inspect the reason, which is only logged via serial. If you see ack timeout 4 right before a disconnect, this might be because of a bug in the AsyncTCP library, for which a fix was included in ESPHome version 1.18.0. If you are running an ESPHome version, prior to 1.18.0, then upgrade ESPHome and build fresh firmware for your devices.

  • We have seen an increase in disconnects while the log level was set to VERY_VERBOSE, especially on single-core devices, where the logging code might be interfering with the operation of the networking code. For this reason, we advise using a lower log level for production purposes.

  • Related to this, seems to be the number of clients that are simultaneously connected to the native API server on the device. These might for example be Home Assistant (via the ESPHome component) and the log viewer on the web dashboard. In production, you will likely only have a single connection from Home Assistant, making this less of an issue. But beware that attaching a log viewer might have impact.

  • Reducing the Delivery Traffic Indication Message (DTIM) interval in the WiFi access point may help improve the ESP’s WiFi reliability and responsiveness. This will cause WiFi devices in power save mode, such as the ESP, to be woken up more frequently. This may improve things for the ESP, although it may also increase power (and possibly battery) usage of other devices also using power save mode.

Component states not restored after reboot

If you notice that some components, like climate or some switches are randomly not restoring their state after a reboot, or you get periodic ESP_ERR_NVS_NOT_ENOUGH_SPACE errors in your debug log, it could be that the NVS portion of the flash memory is full due to repeatedly testing multiple configurations (usually large) in the same ESP32 board. Try wiping NVS with the following commands:

dd if=/dev/zero of=nvs_zero bs=1 count=20480
esptool.py --chip esp32 --port /dev/ttyUSB0 write_flash 0x009000 nvs_zero

Change /dev/ttyUSB0 above to your serial port. If you have changed the partition layout, please adjust the above offsets and sizes accordingly.

Docker Reference

Install versions:

# Stable Release
docker pull ghcr.io/esphome/esphome
# Beta
docker pull ghcr.io/esphome/esphome:beta
# Dev version
docker pull ghcr.io/esphome/esphome:dev

Command reference:

# Start a new file wizard for file livingroom.yaml
docker run --rm -v "${PWD}":/config -it ghcr.io/esphome/esphome wizard livingroom.yaml

# Compile and upload livingroom.yaml
docker run --rm -v "${PWD}":/config -it ghcr.io/esphome/esphome run livingroom.yaml

# View logs
docker run --rm -v "${PWD}":/config -it ghcr.io/esphome/esphome logs livingroom.yaml

# Map /dev/ttyUSB0 into container
docker run --rm -v "${PWD}":/config --device=/dev/ttyUSB0 -it ghcr.io/esphome/esphome ...

# Start dashboard on port 6052 (general command)
# Warning: this command is currently not working with Docker on MacOS. (see note below)
docker run --rm -v "${PWD}":/config --net=host -it ghcr.io/esphome/esphome

# Start dashboard on port 6052 (MacOS specific command)
docker run --rm -p 6052:6052 -e ESPHOME_DASHBOARD_USE_PING=true -v "${PWD}":/config -it ghcr.io/esphome/esphome

# Setup a bash alias:
alias esphome='docker run --rm -v "${PWD}":/config --net=host -it ghcr.io/esphome/esphome'

And a docker compose file looks like this:

version: '3'

services:
  esphome:
    image: ghcr.io/esphome/esphome
    volumes:
      - ./:/config:rw
      # Use local time for logging timestamps
      - /etc/localtime:/etc/localtime:ro
    devices:
      # if needed, add esp device(s) as in command line examples above
      - /dev/ttyUSB0:/dev/ttyUSB0
      - /dev/ttyACM0:/dev/ttyACM0
    network_mode: host
    restart: always

Note

By default ESPHome uses mDNS to show online/offline state in the dashboard view. So for that feature to work you need to enable host networking mode.

On MacOS the networking mode (“-net=host” option) doesn’t work as expected. You have to use another way to launch the dashboard with a port mapping option and use alternative to mDNS to have the online/offline stat (see below)

mDNS might not work if your Home Assistant server and your ESPHome nodes are on different subnets. If your router supports Avahi (eg. OpenWRT or pfSense), you are able to get mDNS working over different subnets following the steps below:

  1. Enable Avahi on both subnets (install Avahi modules on OpenWRT or pfSense).

  2. Enable UDP traffic from ESPHome node’s subnet to 224.0.0.251/32 on port 5353.

Alternatively, you can make esphome use ICMP pings to check the status of the device with the Home Assistant add-on "status_use_ping": true, option or with Docker -e ESPHOME_DASHBOARD_USE_PING=true. See also https://github.com/esphome/issues/issues/641#issuecomment-534156628.

Notes on disabling mDNS

Some of ESPHome’s functionalities rely on mDNS, so naturally disabling it will cause these features to stop working. Generally speaking, disabling mDNS without setting a static IP address (or a static DHCP lease) is bound to cause problems. This is due to the fact that mDNS is used to find the IP address of each ESPHome nodes.

  • You will not be able to use the node’s hostname to ping, find it’s IP address or connect to it.

  • Automatic discovery in Home Assistant when using native API relies on mDNS broadcast messages to detect presence of new ESPHome nodes. If you need to use the native API with mDNS disabled, then you will have to use a static IP address and manually add the ESPHome component with the fixed IP address.

  • Online status detection in ESPHome’s dashboard by default uses mDNS, so disabling mDNS will cause the ESPHome dashboard to show the status of the nodes created without mDNS support to be always offline. Currently, this does not affect any functionality, however if you want to see the online/offline status you could configure ESPHome to ping each node instead. See the notes in the Docker Reference section for more information.

Can Configuration Files Be Recovered From The Device?

If you lost your ESPHome YAML configuration files, there’s no way to recover them. The configuration is not stored on the device directly - only the generated firmware is on the device itself (technically, the configuration can be reverse-engineered from that, but only with a lot of work).

Always back up all your files!

Why shouldn’t I use underscores in my device name?

The top level name: field in your .yaml file defines the node name(/hostname) on the local network. According to RFC1912, underscore characters (_) in hostnames are not valid. In reality some local DNS/DHCP setups will be ok with underscores and some will not. If connecting via a static IP address, there will probably be no issues. In some cases, initial setup using an underscore works, but later the connection might fail when Home Assistant restarts or if you change router hardware. Recommendation: use hyphen (-) instead of underscore if you can.

Important: follow these instructions to use the use_address parameter when renaming a live device, as the connection to an existing device will only work with the old name until the name change is complete.

Why am I getting a warning about strapping pins?

The ESP chips have special “strapping pins” that are read during the bootup procedure and determine how it boots up. They define whether the ESP boots into a special “flashing mode” or normal boot and a couple of other internal settings. If an external pullup/down changes the configured voltage levels boot failures or hard to diagnose issues can happen. While the use of them in software is not a problem, if there’s something attached to the pins (particularly if they’re not floating during the bootup) you may run into problems. It’s recommended to avoid them unless you have a pressing need to use them and you have reviewed the expected boot voltage levels of these pins from the ESP datasheet.

Some development boards connect GPIO 0 to a button, often labeled “boot”. Holding this button while the ESP is turning on will cause it to go into bootloader mode. Once the ESP is fully booted up, this button can be used as a normal input safely.

Strapping pins should be safe to use as outputs if they are only connected to other devices that have hi-impedance inputs with no pull-up or pull-down resistors. Note that I2C clock and data lines do have pull-up resistors and are not safe on strapping pins.

If you are absolutely sure that your use of strapping pins is safe, and want to suppress the warning, you can add ignore_strapping_warning: true to the relevant pin configurations.

How can I test a Pull Request?

By leveraging the external components feature, it’s possible to test most Pull Requests by simply adding a few lines to your YAML! You need the number of the Pull Request, as well as the components that have been added or changed by the Pull Request (they are listed with the “integration:” labels on the GitHub page of the Pull Request). Then, if you add a block of code like the following to your YAML file, once you recompile and flash your device, the code from the Pull Request will be used for the components changed by the Pull Request.

external_components:
  # replace 1234 with the number of the Pull Request
  - source: github://pr#1234
    components:
      # list all components modified by this Pull Request here
      - ccs811

Note that this only works for Pull Requests that only change files within components. If any files outside esphome/components/ are added or changed, this method unfortunately doesn’t work. Those Pull Requests are labeled with the “core” label on GitHub.

Why do entities show as Unavailable during deep sleep?

The Deep Sleep component needs to be present within the config when the device is first added to Home Assistant. To prevent entities from appearing as Unavailable, you can remove and re-add the device in Home Assistant.

See Also