Thanks for the quick replies. Its simple enough for me to assign new unused IPs to one of the interfaces on the new units so as to establish management. In Smartconsole, is there no issue with two firewall clusters having many of the same ip addresses assigned to their interfaces? Especially the management interfaces of the old gateways which will now also appear on the new gateways? SIC will establish to temporary IPs on the new gateways.
Also, when the time comes to commission the new firewalls, can cphastop/cphastart be used for a quick changeover?
For example, remove the old standby gateway from the rack. Active old gateway still in service. Power up new standby gateway and ensure cphastop is run before connecting to the network. Connect to the network and confirm visibility in management.
Run cphastop on the old active gateway and cphastart on the new standby. the new gateway should become active.
Then replace the remaining old gateway.