`
^(10(\.(([0-9]?[0-9])|(1[0-9]?[0-9])|(2[0-4]?[0-9])|(25[0-5]))){3}/([8-9]|(1[0-9])|(2[0-9])|(3[0-1])))|(172\.((1[6-9])|(2[0-9])(3[0-1]))(\.(([0-9]?[0-9])|(1[0-9]?[0-9])|(2[0-4]?[0-9])|(25[0-5]))){2}/((1[2-9])|(2[0-9])|(3[0-1])))|(192\.168(\.(([0-9]?[0-9])|(1[0-9]?[0-9])|(2[0-4]?[0-9])|(25[0-5]))){2}/((1[6-9])|(2[0-9])|(3[0-1])))|(127(\.(([0-9]?[0-9])|(1[0-9]?[0-9])|(2[0-4]?[0-9])|(25[0-5]))){3}/([8-9]|(1[0-9])|(2[0-9])|(3[0-1])))$
`
gm