post http://localhost:3001/rest/json/interfaceLabels
The request body has sets of labels (an object) under the wan and lan keys. In the label object set, the key is the label id, and the value is the label name. Example : {lan: { 1: data, 2:video}, wan: {1: mpls, 2: internet}}
The labels you POST will completely replace the labels saved, and will delete labels you did not pass. If the request fails to delete some labels, it will still succeed but return an error message stating it failed to delete some labels.