How to redirect a user to another server?

Question

Domain Name System

Hello!
Help, please solve the problem. Moved sites to another server and changed ns-servers on the domain.
Now some users who go to the site by domain still have a site located on the old server. Although the domain has already been parked to the new server, and when pinging, there is a ping to the ip of the new server. Why is that? How to solve the problem?

Answer 1

This is called DNS TTL - Time To Live (DNS record lifetime) - the DNS server has the right to cache the old record for the TTL time, and you can’t do anything about it, you need to wait for the TTL to expire.
The correct solution would be to change the DNS TTL before the move, in a time equal to 2*TTL.

Answer 2

On the old server, it was logical to raise the nginx proxy with proxying to the new one