How to make a backup VPS server?

Question

High availability

Hello.
There is a server with several sites on VPS. DNS is stored at a separate host. I want to take a separate VPS from another provider and with a different network. Make it a backup.
How to implement a bundle so that if the first server fails, the second (VPS) immediately starts working? Thus, to ensure the constant operation of sites, for example, when 1 provider has preventive maintenance. Relevance of data is needed from 1 day to 1 week.
What solutions do you recommend?
I've only been working with VPS for 2 weeks...

Answer 1

If speech about DNS - that do not fool around.
Use DNS servers (complete and free)
If you really want stability, then you need to make the server able to address (using BGP) a request to a healthy server.
zilore, selectel
There is also a simpler one - just a second server on afraid (can only work as a secondary).
It's much easier than raising your own server and monitoring it.

Answer 2

1. Set up Master-Master database replication
2. Set up Master-Master file synchronization (I recommend syncthing )
3. Set up a failover on DNS hosting (I recommend zilore , but, more recently - paid)
As a result, we have several replicas that can work simultaneously, or alone. The failover monitors the state of the server and, if it detects a fall in the replica, it switches the NS A-record (IP) to the standby server.