Hi,
There is no migration possible to ensure another instance of VCNS picks the the complete edge configuration and it will manage it further.You could try exporting the rules via Rest api and importing the same to new edge instance.
GET https:///api/3.0/edges//firewall/config will give you firewall config and rest of the steps please do check API guide for vShield.
http://www.vmware.com/pdf/vshield_51_api.pdf
Cheers,
Sree | VCIX-5X| VCAP-5X| VExpert 7x|Cisco Certified Specialist
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