Comment 1 for bug 1307614

Embedding heuristics like this into MAAS is problematic, and will be difficult to maintain as time goes on.

For example, installing to a USB drive instead of a fixed HD sounds like it might be desirable to some people. On the other hand it might also be be a bug in the installer. Then the installer maintainer might argue that it's not a bug, or that it's actually a bug in how the kernel enumerates hardware.

There are probably a thousand other heuristics we _could_ add to MAAS, all in the name of making it Just Work. However, one person's preferred choice is another's bad choice, and in adding an extra layer of behaviour we're also making it harder for users and maintainers alike to reason about how MAAS will behave in a given situation.

For MAAS, my instinct here is to guide users to fix their own problems. Low tech, like having a process which includes removing USB drives before use with MAAS, or higher tech like customising the installer scripts to avoid installing to USB drives. The latter is, I suspect, possible today; documentation or a recipe to work from would be ways to improve the situation.

My other instinct would be to do as hinted at above: report the issue for the installer. MAAS uses d-i and curtin, the latter for fast installs.