How to Fix a DDoS Attack

There are quite a few DDoS protection options which you can apply depending on the type of DDoS attack.
Your DDoS protection starts from identifying and closing all the possible OS and application level vulnerabilities in your system, closing all the possible ports, removing unnecessary access from the system and hiding your server behind a proxy or CDN system.

If you see a low magnitude of the DDoS, then you can find many firewall-based solutions which can help you in filtering out DDoS based traffic. But if you have high volume of DDoS attack like in gigabits or even more, then you should take the help of a DDoS protection service provider that offers a more holistic, proactive and genuine approach.

You must be careful while approaching and selecting a DDoS protection service provider. There are number of service providers who want to take advantage of your situation. If you inform them that you are under DDoS attack, then they will start offering you a variety of services at unreasonably high costs.

We can suggest you a simple and working solution which starts with a search for a good DNS solution provider who is flexible enough to configure A and CNAME records for your website. Second, you will need a good CDN provider that can handle big DDoS traffic and provide you DDoS protection service as a part of their CDN package.

Assume your server IP address is AAA.BBB.CCC.DDD. Then you should do the following DNS configuration:

Create a A Record in DNS zone file as shown below with a DNS identifier, for example, ARECORDID and keep it secret from the outside world.
Now ask your CDN provider to link the created DNS identifier with a URL, something like cdn.someotherid.domain.com.
You will use the CDN URL cdn.someotherid.domain.com to create two CNAME records, the first one to point to www and the second record to point to @ as shown below.

You can take the help from your system administrator to understand these points and configure your DNS and CDN appropriately. Finally, you will have the following configuration at your DNS.

Now, let the CDN provider handle all type of DDoS attacks and your system will remain safe. But here the condition is that you should not disclose your system's IP address or A record identifier to anyone; else direct attacks will start again.

Quick Fix
DDoS attacks have become more common than ever before, and unfortunately, there is no quick fix for this problem. However, if your system is under a DDoS attack, then don’t panic and start looking into the matter step by step.