priority

The priority of this route rule, where 1 is the highest priority. You cannot configure two or more routeRules with the same priority. Priority for each rule must be set to a number between 1 and 999 inclusive. Priority numbers can have gaps, which enable you to add or remove rules in the future without affecting the rest of the rules. For example, 1, 2, 3, 4, 5, 9, 12, 16 is a valid series of priority numbers to which you could add rules numbered from 6 to 8, 10 to 11, and 13 to 15 in the future without any impact on existing rules.