OTA Failed！Failed to Mcumgr DFU: Invalid header magic number

[spring.liu]

why can cause this  problem！ I'm not familiar with NCS OTA

[Einar Thorsrud]

Hi,

The error refers to the magic image number that is used in MCUboot (0x96f3b83d), and that is not found as expected in the image. Where does this .bin file come from? Are you sure it is a valid update image?

[spring.liu]

I use NCS 1.5.1  uart example (ncs1.5.1\nrf\samples\bluetooth\peripheral_uart) add the ota, but fail 

  

 Steps are as follows

1. add this code to prj.conf

CONFIG_BOOTLOADER_MCUBOOT=y

CONFIG_MCUMGR=y

CONFIG_MCUMGR_CMD_IMG_MGMT=y

CONFIG_MCUMGR_CMD_OS_MGMT=y

CONFIG_BT_L2CAP_TX_MTU=252

#CONFIG_BT_BUF_ACL_RX_SIZE=256        this in NCS2.0.0 is ok  but ncs1.5.1 without it   so CONFIG_BT_ACL_RX_COUNT replace it

CONFIG_BT_ACL_RX_COUNT=256

CONFIG_MCUMGR_SMP_BT=y

CONFIG_MCUMGR_SMP_BT_AUTHEN=n

CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=2304

2.add this code to main.c

   

• I used this same approach successfully in NCS2.0  。but NCS1.5.1  without CONFIG_BT_BUF_ACL_RX_SIZE and OTA failed。 the reson is MCUmgr disconnecting

[spring.liu]

and how to open the OTA LOG   

CONFIG_BT_DFU_SMP_LOG_LEVEL=4

CONFIG_BT_DEBUG_LOG =y

CONFIG_LOG_DEFAULT_LEVEL=4

this is only 

[Einar Thorsrud]

Hi,

The only way I am able to reproduce this is by using an invalid image. Can you clarify which image file you use with nRF Connect? You should use the file called "app_update_bin", and this is found under build/zephyr.

[spring.liu]

app_update.zipthis is the    .bin