So, first, make sure you back up all the configs, and the flash. Move them off the controller (i.e. flash drive.tftp, etc.).
Then, you can't manage/config a controller that's associated to a vMM/MM. You need to turn on disaster-recovery:
https://www.arubanetworks.com/techdocs/CLI-Bank/Content/aos8/disatr-recov.htmThat will allow you to change the config. You can try pointing it to another master, or just run it standalone.
So, let us know what you end up doing.
Regards,
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Ambidexter
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