vv181,
Great question.
I tried to figure an answer to your question by doing these steps.
Not sure if it will help in answering your question.
desktop:~$
desktop:~$ sudo nano ~/.bitcoin/bitcoin.conf
/ Deleted everything in ~/.bitcoin/bitcoin.conf
desktop:~$
desktop:~$ cat ~/.bitcoin/bitcoin.conf
/ Nothing is in the file , as expected
desktop:~$
desktop:~$ bitcoin-cli stop
--- > Output:
error: Could not locate RPC credentials. No authentication cookie could be found, and RPC password is not set. See -rpcpassword and -stdinrpcpass. Configuration file: (/home/rasppi3bplus/.bitcoin/bitcoin.conf)
desktop:~$
desktop:~$ sudo nano ~/.bitcoin/bitcoin.conf
/ And added this 1 line only
datadir=/mnt/bitcoin
desktop:~$
desktop:~$ bitcoin-cli stop
/ No problem shutting down. No error messages this time.
..........Reboot the computer. Log in.
No problem getting Bitcoin Core full node as well as Tor running , both automatically.
I confirmed this by running the following commands:
bitcoin-cli getconnectioncount
bitcoin-cli getblockchaininfo
bitcoin-cli getnetworkinfo
systemctl status tor
ls -lt /mnt/bitcoin
df -h
bitcoin-cli getpeerinfo | grep addr