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Under a 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.

sequenceDiagram;
    participant User;
    participant Website;
    participant Server;
    participant Botnet;
    User->>Website: Requests to access site
    Website->>Origin Server: Processes user requests
    Botnet->>Origin Server: Sends a flood of traffic
    Origin Server-->>Website: Slows down due to traffic overload
    Origin Server-->>User: Unable to respond to user requests

Common signs of an attack

Common signs that you are under DDoS attack include:

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