⭐ Merited by n0nce (2)
Also PSA for newbies: Raspberry Pi Model 3B+ with a (fast) USB 3.0 HDD takes literal weeks to sync and verify the whole blockchain. Either have a real desktop (maybe also laptop with enough umph) Linux PC with which you can do the initial sync, then plug the drive into the Pi. Or use an SSD. Just wanting to prevent tons of headache 
I have no RPi expience, but on my laptop it works well to put blocks on HDD and chainstate on SSD.Quote
Especially since in case of an issue with the HDD (give it external power!!), when Bitcoin Core has to restart, it has to re-verify a ton of blocks which can easily add a day or two for each crash that you experience.
The above adjustment made restarting Bitcoin Core much faster. But it wasn't anywhere close to days, just minutes.