Recently, I've been helping several startups with their online business, and I found that many of them suffered DDoS attacks just after their business started, and they were paralyzed as soon as they were hit. The boss was so anxious that he jumped to his feet: “We are using a cloud vendor with its own protection!” Took apart the configuration and took a look, good guy, the basic version of the 5Gbps cleaning capacity, not enough for the hacker to warm up with.
Cyber attacks have long been industrialized these days. The offer to hit a site is clearly marked up, and 50 bucks can paralyze your business for an hour. Expecting basic protection from a cloud vendor? It's the equivalent of blocking a Gatling with a paper shield.
I have handled cases of heavy traffic attacks, 90% team have made a fatal mistake - wait until they are paralyzed before rushing to find a solution. Business interruption for three hours, the loss is enough to buy three years of high defense services. Blood lessons tell us: access to high-defense CDN must become a standard action before the launch, rather than after the fact remedial measures.
The core value of a high-defense CDN is not acceleration, but camouflage. It's like wearing a bulletproof mask to the server - the real IP is hidden behind, and all the traffic first passes through the global cleaning node. Hackers will always hit the CDN nodes, and your source station is hiding in the dark and stable.
Just helped the e-commerce station to carry 380Gbps of mixed attacks, the test found that the properly configured CDN can filter 99% of junk traffic. Today, in the most straightforward way, the high-defense CDN configuration process to dismantle understand. Follow the operation, half an hour will allow the site to wear a bulletproof vest.
First, let's pour cold water: don't believe those “one-click protection” advertisements. I've tested the auto-configuration features of three major vendors, and none of them can perfectly fit the business scenarios. Either the caching rules are unreasonable, or the protection policy is too loose/tight. Manual configuration is always the optimal solution.
The first step in the selection of the most pitted. There are three major schools of high defense products on the market:Traditional Manufacturer Type(CDN5, CDN07),Cloud Service Provider Binding Stereotypes(a certain Riyun, a certain Tencent cloud),Specialized protective(08Host, etc.). It's interesting to see how the real-world data compares:
The nodes of traditional vendors cover a wide range, but the degree of customization is low. CDN5's Asia-Pacific node latency can be pressed to less than 80ms, but the European cleaning ability is weak; CDN07's TCP acceleration algorithm is really fast, but the configuration of the background is anti-human.
The biggest pitfall of the cloud vendor's bundled stereotypes is that you think you are buying an independent high defense, but in fact, it is still a shared cluster. Peak period may be “golden customers” to seize resources. Last year's Double Eleven, an e-commerce company suffered this loss.
Specialized protection type like 08Host, winning in the protection strategy fine. Support customized protection templates by business type (e-commerce/gaming/finance), but the price is often expensive 30%.
My suggestions for choices areThe main business in Asia-Pacific choose CDN5, global business with CDN07, financial level protection needs to consider 08Host. do not believe that the sales blow “unlimited protection”, all vendors have invisible thresholds.
Determine the manufacturer and go straight to the console. Focus on four parameters:source return method、Cache Rules、protection class、bandwidth limit. There are mines buried in every option here.
Once a customer configured the next day the source station was penetrated, check to the end found that the selection of the “transparent back to the source” - the hacker through the CDN node counter-checking to get the real IP. be sure to select the “proxy back to the source It is important to use the ”proxy back to the source" mode, so that the CDN as an intermediary to isolate the traffic.
The domain name binding link is the most testing details. Many people directly fill in a CNAME and think it's done, but forget to check the resolution status. The correct posture should be:
Next, configure the return source policy. The source station IP must use the intranet IP or firewall whitelist IP, to prevent the exposure of public IP. There have been hackers who have violently scanned the IP of CDN segments to counter-check the source station, because the public IP was used to return to the source.
Cache configuration is performance critical. It is recommended to set up a 30-day cache for static resources and turn off the cache for dynamic APIs. There is a classic misunderstanding: some people have cached the login interface, and as a result, all user logins are serialized. Use this rule to avoid tragedy:
WAF rules are not the more stringent the better, I've seen some people open the full strict mode, the normal user also intercepted. It is recommended to take three steps:Medium protection for initial use，Documentation of learning traffic patterns，Move to custom strategy after two weeks。
There are three must-open protection items:CC Attack Protection(Automatically challenged by requests over 200 per second),Geographical closure(Direct blocking of non-business area IP segments),Malicious Bot Interception08Host's Bot recognition does a particularly good job of distinguishing between search engines and malicious crawlers.
There's a hidden artifact in the advanced settings:Man-machine validation thresholdsYou can set “the same IP access 50 times per minute to trigger the authentication code”. You can set "the same IP access 50 times per minute to trigger the verification code", the actual test can block 80% CC attack. But don't set it too low, or mobile users will curse.
Always test at the end! Verify that the protection is working by simulating an attack with the tool:
Check the attack report on the CDN console, normally you should see the attack traffic being cleaned and the source server pressure rippling. If you find the source CPU spiking, quickly check back to the source configuration.
Don't forget to set alarms. It is recommended to turn on the “cleaning traffic within 5 minutes exceeds 10G” and “back to the source bandwidth exceeds 100Mbps” two threshold alarms. If you are attacked at three in the morning, you can still respond in time.
After these five steps, your site has been able to carry most conventional attacks. But remember, there is no absolute security system. Last month, I encountered a perverted attack: hackers used tens of thousands of real cell phone IP to launch a slow request, almost bypassing the high defense strategy. In the end, it was only by relying on 08Host's intelligent behavioral analysis that it was stopped.
High-defense CDNs essentially buy time - dragging the hacker into a war of attrition until he gives up the attack. So the bandwidth reserve is very important. It is recommended to reserve 20% bandwidth margin on a daily basis, and temporarily expand the capacity when encountering an attack.CDN5's elasticity expansion does a good job, five minutes to add 1T protection bandwidth.
Finally, the truth: 90%'s successful attack stems from a configuration error. Regularly auditing CDN rules and checking source site logs for unusual direct access is more important than buying overpriced protection packages. After all, the strongest fortresses are often breached from within.
Go check your CDN configuration now. Don't wait for an attack to come before you regret it - with this security stuff, it's always too much of a redundancy in normal times and too little of a hate when things go wrong.
