Device Management Client 4.11.0 General Availability

Known issues:

• [Linux/Zephyr] Asynchronous DNS does not work well, and the device fails to reconnect to the cloud if some of the pods are restarted. In such a scenario, the device needs to be restarted.
  To address this issue, the default DNS settings should be overridden to synchronous DNS in the application level:
  • For Linux devices, set the PAL_DNS_API_VERSION flag to 0.
  • For Zephyr devices, set the DNS API selection to POSIX.

Device Management Client

• Removed content type ct= field from the register message payload.
• Bootstrap LWM2M compliance:
  • Bootstrap message parsing extracts instance ID from Uri-Path or from the payload.
  • Security instance IDs are no longer hardcoded but are in line with the bootstrap-server resource boolean value.
  • Extended DELETE to paths other than 0 and 0/0.
  • Updated to ignore and not fail when not supported optional resources are included in bootstrap PUT requests.
  • Bootstrap done is triggered on receiving ACK to separate CHANGED response to the bs finish POST request. Previously, bootstrap done was relying only on ssl peer close notification.
  • Client has a new configuration flag MBED_CLIENT_DYNAMIC_OBSERVABLE, which controls APIs such as set_observable(). The purpose of these features is to control whether the resource can be observed from the cloud. When enabled, the Client also appends the "obs" parameter to the resources as part of the registration message. If disabled, all resources are always observable, and you don't need to specify such capability separately. As part of improving LwM2M compliance and cleaning up the code base, this feature is wrapped behind this feature flag that is currently enabled by default. In the future, we plan to disable and eventually remove the feature completely.
• Add support to collect and store trace output to NVM for later review.
  • You can enable this option by defining compile-time macro MBED_CONF_MBED_CLIENT_DYNAMIC_LOGGING_BUFFER_SIZE. This defines the size of a RAM buffer. When the buffer is full or trace level trigger is found, the buffer content is stored in NVM.
  • When enabled, these resources are published, and you can use them to control logging:
    • 33456/0/1 Start log capture.
    • 33456/0/2 Stop log capture.
    • 33456/0/3 Read current logs from NVM.
    • 33456/0/4 Erase existing logs from NVM.
    • 33456/0/5 Trace level output. Accepted values are: CMD (0), ERROR (1), WARN (2), INFO (3), and DEBUG(4).
    • 33456/0/6 Trace level trigger. Accepted values are: DISABLED(0), ERROR (1), and WARN (2). The default value is ERROR. If disabled, all trace lines defined by trace level are stored in NVM.
    • 33456/0/7 Size of the NVM in bytes.
    • 33456/0/8 Auto erase NVM when full, disabled by default.
    • 33456/0/9 Is capture currently enabled/disabled.
    • 33456/0/10 Size of unread logs in NVM.
    • 33456/0/11 Error, SUCCESS(0), STORAGE FULL(1), READ FAILURE(2), WRITE FAILURE(3), ABORTED(4), OUT OF MEMORY(5).
    • 33456/0/12 Total size if logs in NVM.
  • The application can also start and stop capture using MbedCloudClient::set_dynamic_logging_state(bool state) API.
• Extended the MbedCloudClient::setup() API to allow the application to trigger full registration.

Device Management Update Client

• [Linux] Added support for FOTA combined update, a coordinated and simultaneous installation of multiple images on a device. The new MBED_CLOUD_CLIENT_FOTA_SUB_COMPONENT_SUPPORT macro enables this. To enable a combined update on a device, register a device component that consists of the relevant subcomponents that need to be updated together. FOTA_MAX_NUM_OF_SUB_COMPONENTS defines the maximum number of supported sub-components.
• Deprecated component update callback prototypes. Customers using Pelion Device Management Client 4.11 and higher should use the new component update callbacks.
  • Deprecated the verify-after-installation callback (fota_component_verify_install_handler_t). Use the fota_comp_verify_cb_t callback instead.
  • Deprecated the installation callback for non-Linux targets (fota_candidate_iterate_handler_t). Use the fota_comp_install_cb_t callback instead.
  • Deprecated the installation callback for Linux targets for component update (fota_app_on_install_candidate). For component update, use the fota_comp_install_cb_t callback. To update the main application, use fota_app_on_install_candidate.
  • Added the fota_comp_finalize_cb_t installation finalization callback for future use (not in use yet).

Platform Adaptation Layer (PAL)

[Linux] Enabled PAL_DNS_API_VERSION 3 by default for Linux configurations.

Release notes can be found from:
https://cloud.mbed.com/docs/current/release-notes/device-management-client.html