Starting out, confusion about nameservers and hosts

#1

Hey
I’m not real clear on how this works although I have transferred some domains into my Cloudflare account and they seem to work ok.
I want to get all of my domains out of GoDaddy and into Cloudflare, but if I change nameservers then the sites will go down… I think?
When I migrated my personal WP blog over to new host (SiteGround) I had to update the nameservers, which removed it from Cloudflare.
If I update them back to Cloudflare, won’t that mean the site won’t work?
Just a bit confused about adding or removing nameservers and how that connects with the actual live website.
Thanks in advance.

#2

There are a few parts of the puzzle:

  1. Your domain name – It’s registered somewhere, and along with that registration, you tell it which name servers to use.
  2. The name servers – If you add a site to your Cloudflare account, Cloudflare will scan your current name servers for all the standard DNS entries and copy them into your account. You need to double-check this by comparing your Cloudflare DNS to your current host’s DNS.
  3. Once this step is complete, go back to #1 and set your domain registration to use the Cloudflare name servers. Since you already copied your DNS records, there will be no down time.
  4. If you change hosting (the server your site is on), you need to update Cloudflare’s DNS with your new records. Again, comparing Cloudflare’s DNS records with the records at your now-new host. There won’t be any real downtime if you haven’t cancelled your old hosting yet. It takes 5 minutes for your DNS changes to take effect.

If you change name servers away from Cloudflare, then back, it really drags out the process. Just make sure your DNS records match for when name server updates take hold. This can take up to a couple of days.