Cloudflare Docs
Cloudflare Fundamentals
Cloudflare Fundamentals
Visit Cloudflare Fundamentals on GitHub
Set theme to dark (⇧+D)

How to tell if you are under DDoS attack

A distributed denial-of-service (DDoS) attack is where a large number of computers or devices, usually controlled by a single attacker, attempt to access a website or online service all at once. This flood of traffic can overwhelm the website’s origin servers, causing the site to slow down or even crash.


​​ Common signs of an attack

Common signs that you are under DDoS attack include:

  • Your site is offline or slow to respond to requests.
  • There are unexpected spikes in the graph of Requests Through Cloudflare or Bandwidth in your Cloudflare Analytics app.
  • There are strange requests in your origin web server logs that do not match normal visitor behavior.