For guarding, and situations with a minimal RTO SLA, I use PgPool-II to manage the cluster, automatic failover and Virtual IP address. Note that only two database servers are needed. Install PgPool on the two DB servers, and a third, smaller system.
There are other products which do the same thing as PgPool, and you might find them better.
> Hi, > 1- Both split-brain protection and security. Any tool? > > 2- Consider a database related to a website, which data is regularly > entered. Now you want to transfer this database to another server. > What's the solution?