This is how one might back up their Bitcoin Core data directories in order to save time on syncing in the future:
#!/usr/bin/bash
local_d=/root/btc_db
rsync -av --delete chainstate "$local_d"
rsync -av --delete blocks "$local_d"
Sometimes backups to a remote location take quite a long time, and so there may a lag of many
block in between rsync -av --delete chainstate "$local_d"
and rsync -av --delete blocks "$local_d"
. Will Bitcoin Core sync seamlessly, e.g. without having to wait for bitcoind -reindex
to finish, when being fed chainststate/
backup that corresponds to a different block height
than blocks/
?