Robtex

Up: 137.189.128.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 137.189.128.0/23
Down right: 137.189.130.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
137.189.128.3	A+PTR	med.cuhk.edu.hk
137.189.128.3	A+PTR	mailserv.med.cuhk.edu.hk
137.189.128.3	A+PTR	ruby.med.cuhk.edu.hk
137.189.128.190	A+PTR	iceberg.med.cuhk.edu.hk
137.189.131.237	A+PTR	serverd-law.law.cuhk.edu.hk