This read-create Integer32, ranging 1 to 65535, sets the selection priority among multiple IP addresses resolved for the same domain name, with lower numeric values preferred (preference 1 beats preference 2), and per the description this value must be unique among addresses of the same domain name and cannot be modified after row creation. An admin uses this to control which of several redundant MGC addresses gets tried first when a domain name resolves to more than one IP. Because it can't be changed post-creation, reordering address preference requires deleting and recreating the affected resolution entries.