Robtex

Up: 217.28.8.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 217.28.12.0/23
Down right: 217.28.14.0/23

IP	Type	Hostname
217.28.12.74	PTR	adsl217.28.12.74.manx.net
217.28.12.155	PTR	adsl217.28.12.155.manx.net
217.28.12.204	PTR	adsl217.28.12.204.manx.net
217.28.13.2	PTR	adsl217.28.13.2.manx.net
217.28.13.27	PTR	adsl217.28.13.27.manx.net
217.28.13.251	PTR	adsl217.28.13.251.manx.net
217.28.13.251	A	mail.ermac.co.uk
217.28.14.59	PTR	adsl217.28.14.59.manx.net
217.28.14.213	PTR	adsl217.28.14.213.manx.net