Symptoms:
- Nothing appears on 'disk print'
- Nothing new appears on 'system resource usb print' (Only the host controllers, which are there all the time)
- I'm running on 6.37.1
- Tried 'system routerboard usb set usb-mode=force-host' and also 'automatic'
- Reformatted and resized partition to 2GB. Tried FAT32 and ext3
- Rewrote the MBR
- Rebooted the device, power-reset, unplugging etc trivial things
- Four different USB 2.0 disks, sizes 4GB and 8GB
- Two different models (and two of each model) USB 3.0 disks, sizes 16GB and 128GB
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SOLVED: I have solved the issue. They provided me with a new router and it works. Probably previous one was just faulty.