We're considering a 3CX Fail-over in our office but reading about it a couple of questions arise on what is needed: * I see you need a "full" additional license for the backup/fail-over server. Can this license contain less concurrent calls? e.g. Main server has 64 simultaneous calls, can the backup have "only" 32? * The backup runs on another IP, I reckon you need special phones which have a fail-over system for automatically connecting to the secondary server with a different IP, or do you need to provision the phones (again) ? * How do gateways handle an IP-change?