I'm consulting for a cyber-security company.
The company's product is a hardware device installed with Ubuntu 14.04 which resides in remote customers sites.
There's a management API in these devices which allows connecting to them and running scripts.
There's a motivation to upgrade all the hardware devices (in customers remote sites) to Ubuntu 18.04 and this process should be fully unattended.
As far as I know, when upgrading a major version, grub files are edited and usually, it requires the user to choose which version of grub configuration file should be used.
The grub package is only an example and I'm sure there are many more such packages which require some human intervention.
Is there any known method to accomplish such a task?