How to quickly transfer a domain to a new IP?

Question

Domain Name System

Good afternoon.
The situation is this. Hosting is under DDoS attack.
The site is deployed from a backup on another site.
How to quickly rewrite the A record of a domain name to a new IP?
Is there some way to do this without waiting "up to 48 hours for all DNS caches in the world to be completely updated"? Let's say a break in work no more than an hour.

The question describes a real situation that happened to us last year. It was not possible to quickly rewrite the domain record, and therefore the site was not available to a large number of visitors (attendance at that time was about 15k uniques, everything fell to the peak of attendance). A normal DNS update was completed after the hosting was restored (that is, in fact, you could do nothing, it would not affect the result).
Now I want to foresee such a situation in the future and lay its solution to the architecture.
Can you tell me something?
I think that services like Yandex solve this with their own subnet, several providers and dynamic routing. Unfortunately, we don't have enough money for this.
Are there other solutions?

Answer 1

Alternatively, you can reduce the zone TTL to a few minutes. The disadvantage of this approach is that the number of requests to the DNS servers will increase and the time it takes users to open pages may increase.

Answer 2

Just reduce TTL. Only in advance.

Answer 3

In the DNS, register 2 IPs at once (2 A records), disable the second one. On the second IP is a backup site. A huge minus is the brakes (round robin gives a random ip and half of the users will make requests to a disabled server).
It is solved by installing your own ns server with a smart definition of which ip to give at the moment, well, and reducing the TTL

Answer 4

Here's an option: aws.amazon.com/route53/ - there for a few minutes.
CloudFlare or qrator.net are another option (qrator handles ddos ​​attacks well, by the way).