OTA Updates

LwM2M supports over-the-air (OTA) firmware and software updates using standardized objects. Before proceeding, read the OTA Updates guide to understand how to upload and manage packages in ThingsBoard.

Firmware Updates (Object 5)

LwM2M Object 5 (Firmware Update) handles firmware delivery and installation.

Required Observations

Configure these resource observations in the device profile to track update progress:

Resource	Key	Description
`/3/0/3`	`firmwareVersion`	Current firmware version
`/5/0/3`	`state`	Firmware update state
`/5/0/5`	`updateResult`	Result of the last update attempt
`/5/0/7`	`pkgVersion`	Target firmware package version

Firmware Update Strategies

Select the strategy in Device profile → Transport configuration → Other settings:

Strategy	How it works
Push via Object 5 / Resource 0 (Package)	ThingsBoard pushes the binary directly to the device via block-wise CoAP transfer
Pull via Object 5 / Resource 1 (Package URI)	ThingsBoard generates a CoAP URL; the device downloads the firmware from that URL
Push via Object 19 / Resource 0 (Data)	Alternative binary push using Object 19

After the package is delivered, trigger installation using the Execute RPC:

{"method": "Execute", "params": {"id": "/5/0/2"}}

Software Updates (Object 9)

LwM2M Object 9 (Software Management) handles software delivery, installation, and activation as two separate phases.

Required Observations

Resource	Key	Description
`/3/0/19`	`softwareVersion`	Current software version
`/9/0/0`	`pkgName`	Software package name
`/9/0/1`	`pkgVersion`	Software package version
`/9/0/7`	`updateState`	Software update state
`/9/0/9`	`updateResult`	Result of the last software update

Software Update State Transitions

Step	State	Result	Description
1	`INITIAL (0)`	`INITIAL (0)`	Before any download
2	`DOWNLOAD_STARTED (1)`	`DOWNLOADING (1)`	Download in progress
3	`DOWNLOADED (2)`	`DOWNLOADING (1)`	Package downloaded and verified
4	`DELIVERED (3)`	`SUCCESSFULLY_DOWNLOADED_VERIFIED (3)`	Ready to install
5	`INSTALLED (4)`	`SOFTWARE_SUCCESSFULLY_INSTALLED (2)`	Installation complete
6	`INITIAL (0)`	`INITIAL (0)`	Returned to initial after uninstall

Software Update Strategies

Strategy	How it works
Push via Object 9 / Resource 2 (Package)	Binary pushed directly to the device
Pull via Object 9 / Resource 3 (Package URI)	ThingsBoard generates a CoAP URL; device downloads the software package

Object 19 — OTA Metadata (Optional)

ThingsBoard optionally uses Object 19 to deliver OTA metadata before the actual package transfer. Enable it in Device profile → Transport configuration → Other settings → Use Object 19 for OTA file metadata.

When enabled:

ThingsBoard checks whether Object 19 is supported at device registration.
Creates an Object 19 instance (InstanceId 65534 for firmware, 65535 for software).
Writes a Base64-encoded JSON metadata payload to that instance.

Metadata structure:

{
  "Checksum": "SHA256 hash of the file",
  "Title": "OTA package name",
  "Version": "Target version string",
  "File Name": "Filename for device storage",
  "File Size": "Size in bytes"
}

Testing OTA with the Demo Client

The ThingsBoard LwM2M Demo Client simulates Object 5, Object 9, and Object 19 for OTA testing.

Clone and build:

git clone https://github.com/thingsboard/thingsboard.lwm2m.demo.client
mvn clean install

Run with OTA support enabled (-tota flag):

java -jar thingsboard-lwm2m-demo-client-{version}.jar -u coap://lwm2m.thingsboard.cloud:5685 -n MyClientNoSec -tota

The demo client logs all state transitions — use it to validate the firmware update strategy and Object 19 metadata delivery configured in the device profile.

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