LAVA waits for 'Linux version' string to start waiting for login
prompt. Matching this string tells LAVA that bootloader stage is
completed. This is why your developer build still works. Do I
understand correctly that the production image doesn't output anything
until login prompt? If this is true auto login action needs to be
tricked somehow. I'll check if I can come up with proper solution.

milosz

Hello,

thanks to Dean Birch suggestion we solved  the issue specifying the kernel_start_message to an empty string.
See PR: https://github.com/ARMmbed/mbl-tools/pull/351/
This works for now but in the future we might be disable the login prompt altogether hence we need an alternative solution to that.
The idea is that we might have some polling process on the LXC that checks if the board has booted properly.

Cheers
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