AWS S3能否抵御请求攻击？免费层超量请求后果咨询

Hey there, let's walk through exactly what you can expect if your personal site's S3 bucket gets hit with a malicious looped request attack that pushes you over the 20,000 monthly GET request limit of the free tier.

Key Consequences to Know #

• You'll incur overage charges
  Once you exceed the free tier's 20k GET requests, AWS will bill you for every additional request at the standard pay-as-you-go rate. As of 2024, this is roughly $0.0004 per 1,000 GET requests (so $0.40 for 10,000 extra requests, $4.00 for 100,000, etc.). These charges will show up on your next monthly AWS bill—there's no "hidden" fee or sudden huge bill unless the attack scales to an extreme degree (millions of requests).

• AWS will send you billing alerts (if you set them up)
  Before you hit the limit, AWS can notify you via email if you've configured billing alarms in the AWS Billing Dashboard. It's a good idea to set these up now—you can set alerts for when you reach 80% of your free tier limit, or when your monthly charges hit a threshold you're comfortable with. If you do exceed the limit, you'll also get a notification once the billing cycle closes.

• Your S3 service won't be immediately suspended
  Unlike some smaller providers, AWS doesn't shut down your S3 bucket right away for exceeding free tier limits. Your site will stay up and accessible—you'll just be charged for the extra requests. The only time service suspension comes into play is if you fail to pay the resulting overage bill, or if the attack violates AWS's Acceptable Use Policy (which malicious bot traffic typically does, but suspension is a last resort).

Quick Safeguards to Prevent This #

Since you're running a personal site, here are some simple steps to mitigate this risk without too much hassle:

• Set up CloudFront as a CDN
  CloudFront has its own free tier (50GB of data transfer and 10 million requests per month) that pairs perfectly with S3. It caches your content at edge locations, so most visitors won't hit your S3 bucket directly—cutting down on GET requests drastically. Plus, you can add AWS WAF (Web Application Firewall) rules to block malicious bot traffic and request loops.
• Enable S3 Access Logs
  Turning on access logs for your bucket lets you track where requests are coming from. If you notice a sudden spike from a single IP or bot, you can quickly block it using bucket policies or CloudFront WAF.
• Limit request rates (optional)
  You can use S3 Bucket Policies or AWS WAF to set rate limits on requests, preventing a single source from flooding your bucket with thousands of requests in minutes.

Hope this helps you feel more prepared! If you need help walking through setting up any of these safeguards, just ask.

内容的提问来源于stack exchange，提问作者Simon Willan