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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.

UserWebsiteServerBotnetOrigin ServerRequests to access siteProcesses user requestsSends a flood of trafficSlows down due to traffic overloadUnable to respond to user requestsUserWebsiteServerBotnetOrigin Server

​​ 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.