[jobroco]

Zulan,
SIC is the "Secure Internal Communications" methodology that Checkpoint uses to ensure that the SmartCenter Server is securely communicating with the gateways that it's managing. You can check on the General Properties of the Checkpoint Gateway object in SmartDashboard to see this option. You can test it and reset it by clicking the Communication button. If you click on Communication the Test it will let you know if SIC is set. Reset it if necessary. Next, to make sure the topology is set properly you need to look under the Topology settings for the gateway object (just under General Properties on the left). Click on the Get button to retrieve the Interfaces with topology. You can then edit each network interface to define anti-spoofing. By changing the OS of your gateway the naming convention and MAC addresses of your nics has changed. So having the new gateway's ip's set to the same as the existing isn't mandatory (but could ease with limiting changes in your rulebase). It's more necessary to ensure that the Smartcenter server understands which hardware address (MAC) for SIC and topology to bind to. Good luck.
-jj