RancherOS not starting after power outage

For testing purposes, I switched off my power supply while the system was running. (to simulate power outage)
Now it doesn’t boots. It can’t find a boot device. Is there any why I can get it to work again, or do I need to reinstall the OS. (I’m able to boot into a RancherOS pendrive )
RancherOS: version 1.3.0
System specs: MB: Gigabyte H61M-S2PV, CPU i3-2120, RAM 4GB, 2*1 TB HDD (RancherOS intalled on first drive)

I hope I posted it in the right place and sorry for my english.

My guess is that RancherOS was running from memory and therefore there is nothing to boot from. In this case, you would want to install RancherOS on disk.

I’m no RancherOS expert and frankly, I’m also here looking for answers…