Robtex

Up: 216.131.32.0/19
Can't show all results, try to descend to a more specific CIDR
Down left: 216.131.48.0/21
Down right: 216.131.56.0/21

IP	Type	Hostname
216.131.49.17	A	cert01.53.com
216.131.49.18	A	cert02.53.com
216.131.49.31	A	wlbx-dr.53.com
216.131.49.111	A+PTR	np.sso.53.com
216.131.49.210	A	rlbx-dr.53.com
216.131.50.120	A	mft-test.53.com
216.131.54.20	A	ra2.53.com
216.131.54.25	A+PTR	ns3.fifththird.net
216.131.54.25	A	ns2.fifththird.net
216.131.54.26	A	ns5.fifththird.net
216.131.54.32	PTR	mailgw7.53.com
216.131.54.33	A	mailgw8.53.com
216.131.54.34	A	mailgw8.53.com
216.131.54.42	A	mailgw2.fifththirdbank.com
216.131.54.51	A	sa2.53.com
216.131.54.52	A+PTR	vpn2.53.com
216.131.54.55	A+PTR	remotetrain2.53.com
216.131.54.55	PTR	sharefile-dr.53.com
216.131.54.90	A	csi.53.com
216.131.54.100	A+PTR	mailgw9.53.com
216.131.54.118	A+PTR	goodproxydr.53.com