Hello I'm a new in Redis. Is it possible to synchronize masters between themselves and if some will drop others will work?
You do not syncronize primaries (masters) between them. You create another redis server with a replica (slave) role. The primary and replica talk to each other and get syncronized.
In case the primary fails, the replica becomes the primary and start serving client request. When your original primary came back to live again, it will be a replica or the promoted replica (now the primary)
This promotion magic can be automatically achieved using Redis Sentinel or Redis Cluster
Some interesting links you should read