What is Web OTA Update?

CheapoDC supports an HTTP-based Over-the-Air (OTA) firmware update mechanism that leverages the esp32FOTA library from Chris Joyce. Web OTA Update is available in CheapDC as of firmware version 2.2.0. Notification of an available update is shown in the CheapoDC Web UI on the Device Management page. Web OTA Update will update both the ESP32 firmware and data partitions while preserving your CheapoDC configuration.

Web OTA Update Steps

  1. Backup your CheapoDC configuration files. Use the File Management page to download the CDCConfig.json and CDCWifi.json files just in case there is a problem and you need to recover them.
  2. Go to Web OTA Update on the Device Management page. If a new release of CheapoDC firmware is available then the new release version will be displayed.
  3. To start the update process enter your CheapoDC password in the password field then click the Update button.
  4. Information about the progress of the update will be displayed in the Update Progress section above the Web OTA Update section.
  5. Once the update is successfully completed, the CheapoDC will automatically reboot and the Device Management page should refresh about 5 seconds after the reboot message is displayed.

Web OTA Update FAQ

CheapoDC will check for the availability of a new release of firmware when it boots up. If a new release is available then a notification will be shown in the Web UI on the Device Management page in the Firmware Update section.

Before doing the update remember to backup your configuration files. Enter your CheapoDC password and then click the "Update" button on under Web OTA Update to start the update process.

Yes, your configuration will be preserved during the update process. The first step of the update process is to backup both configuration files to CheapoDC memory. Then the files will be restored after the updated data partition is written. However, you should backup your configuration files before doing an update just in case there is a problem.

The update process should only take a couple minutes to complete. Progress will be displayed in the Update Progress section. The update steps are to:
  1. backup the configuration files,
  2. update the data partition,
  3. restore the configuration files to the updated data partition,
  4. update the firmware partition,
  5. then reboot the CheapoDC.

An error will be displayed in the Update Progress section if any of the update steps fail. The ESP32 is well designed for OTA firmware updates with dual firmware partitions protecting against firmware corruption during OTA updates. Unfortunately the data partition is not similarly protected. If your Web OTA Update fails, note the error message then reboot the CheapoDC. You should be able to try the update again using the Web UI. If you cannot connect to the Web UI after reboot then the data partition may be corrupt. Use the WebFlash tool to re-Flash your CheapoDC to a fresh state. Then restore the configuration files you downloaded before doing the Web OTA Update. Use File Upload on the Web UI File Management page.

With the Web OTA Update you can only update to the latest version available. If you want to update to a previous version you will need to download the previous release from GitHub and then build and install it with the Arduino IDE.

The firmware and data partition images are stored on GitHub and downloaded using authenticated HTTPS. The security is at least on par with downloading the source from GitHub and building the firmware yourself.