Thank you! that Rsync looks perfect for what I want, I had a quick read about it and I think I`ll probably go the Grsync route and see what others are doing ith it and just copy the one that`s closest to my needs.
I have 16Gb or ram and no room to fit any more in there really, it`s going to have be enough.
as for Why I want to do this, it`s because before I started out I made my mind up that I was going to be the best possible node runner I could be with the least amount of downtime as I could manage, I even have battery backed internet in case the power goes down. I didn`t want to build some janky pile of rubish just to say I`m a node runner, I wanted to do a good job and be as reliable as possible and not have to be repairing it every couple of days, which includes waiting another 2 days 5 hours for the blocks to be re-synced again if one of my drives fails, this way I can be up and running again in a few hours at most.