Lenovo E460, 8GB RAM, Fedora 26, bitcoin core command line version 0.16.0, All blocks completely downloaded on a flash drive with 256GB capacity.
I rebooted my machine today without stopping the bitcoind before and since then the following happens: 1) starting "bitcoind -daemon -datadir=/path/to/flash/drive" 2) I see with "top" the process 'bitcoind' running for about 30-45 seconds 3) Suddenly under same process id the process names changes to "bitcoin-shutdown" and disappears a second after. 4) Stop or new start of bitcoind is not possible, message is "Error: Cannot obtain a lock on data directory /path/to/flash/drive. Bitcoin Core is probably already running." 5) Only way to start bitcoind again is to reboot the linux. Then loop 1)-5) starts again.
Any help appreciated! Thanks!