Robtex

Up: 129.6.12.0/22
Can't show all results, try to descend to a more specific CIDR
Down left: 129.6.14.0/24
Down right: 129.6.15.0/24
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
129.6.15.23	PTR	project.nist.gov
129.6.15.26	A+PTR	time-e-g.nist.gov
129.6.15.27	A+PTR	time-d-g.nist.gov
129.6.15.27	A	ntp1.glb.nist.gov
129.6.15.28	PTR	time-a-g.nist.gov
129.6.15.28	A	ntp.svc.us.xo.net
129.6.15.28	A	ntp.lorexddns.net
129.6.15.29	PTR	time-b-g.nist.gov
129.6.15.30	PTR	time-c-g.nist.gov
129.6.15.30	A	3.lede.pool.ntp.org
129.6.15.30	A	3.cloudlinux.pool.ntp.org
129.6.15.32	A	ntp-g.nist.gov
129.6.15.44	PTR	mnets001.nist.gov
129.6.15.45	PTR	mtmonitor.nist.gov
129.6.15.250	A	nts15s225a02a.nist.gov
129.6.15.251	A	nts225ccf15-s53.nist.gov
129.6.15.251	A	e225a02s53e.netg.nist.gov