you probably got lost by copy and pasting that command. those have to be double dashes for the exclude options, like –exclude=
rsync -auHxv --numeric-ids --exclude=/etc/fstab --exclude=/etc/network --exclude=/proc --exclude=/tmp --exclude=/sys --exclude=/dev --exclude=/mnt --exclude=/boot --exclude=/root root@SOURCE:/ / https://lowendbox.com/blog/how-to-migrate-a-hosted-server-in-5-easy-steps-with-rsync/
An Example of Rsync at Work
Assuming you are logged into the destination server, you’d implement a command that looks like this:
rsync -auHxv –numeric-ids –exclude=/etc/fstab –exclude=/etc/network/* –exclude=/proc/* –exclude=/tmp/* –exclude=/sys/* –exclude=/dev/* –exclude=/mnt/* –exclude=/boot/* –exclude=/root/* root@SRC-IP:/* /