This value is an identifier used to distinguish between multiple route entries that share the same destination address and mask. An admin uses this when more than one route exists to the same destination and mask pair, such as multiple static routes, to tell those entries apart in the table, and for static routes this tag can be configured by the user. For example, two static routes both destined for 10.0.0.0/255.0.0.0 but via different next hops would carry different zxr10rtmLabelReTag values so they appear as distinct table entries.