Pro Turm wrote 27.10.2021 14:26:
How about the case A->B->C, and B fails? Will A be replicating directly to C ?
No.
What does a switch from primary <-> replica mean? Only changing the configuration files?
No, it is invoking "gfix" command with appropriate switches as described in README.replication.txt.
Restarting the servers: are there some performance issues expected due to restarting (looising data, long-time unavailability etc.) ?
It depends. -- WBR, SD. Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel