Robtex

Up: 123.255.64.0/18
Can't show all results, try to descend to a more specific CIDR
Down left: 123.255.96.0/20
Down right: 123.255.112.0/20

IP	Type	Hostname
123.255.96.29	A	ip-123-255-96-29.wlan.cuhk.edu.hk
123.255.103.74	A	ip-123-255-103-74.wlan.cuhk.edu.hk
123.255.103.167	A	ip-123-255-103-167.wlan.cuhk.edu.hk
123.255.103.204	A	ip-123-255-103-204.wlan.cuhk.edu.hk
123.255.106.179	A+PTR	ip-123-255-106-179.wlan.cuhk.edu.hk
123.255.108.159	PTR	ip-123-255-108-159.wlan.cuhk.edu.hk
123.255.117.164	PTR	ip-123-255-117-164.wlan.cuhk.edu.hk