Robtex

Up: 123.243.56.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 123.243.56.0/23
Down right: 123.243.58.0/23

IP	Type	Hostname
123.243.56.63	A	123-243-56-63.tpgi.com.au
123.243.56.87	A	123-243-56-87.static.tpgi.com.au
123.243.56.100	A	123-243-56-100.tpgi.com.au
123.243.56.209	A	sexynails.com.au
123.243.56.213	A	123-243-56-213.tpgi.com.au
123.243.57.234	PTR	123-243-57-234.static.tpgi.com.au
123.243.58.60	A+PTR	123-243-58-60.static.tpgi.com.au
123.243.59.16	A	123-243-59-16.tpgi.com.au