Robtex

Up: 27.123.16.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 27.123.16.0/23
Down right: 27.123.18.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
27.123.16.3	PTR	tig-net16-3.trueintergateway.com
27.123.16.18	PTR	tig-net16-18.trueintergateway.com
27.123.16.97	PTR	tig-net16-97.trueintergateway.com
27.123.16.111	PTR	tig-net16-111.trueintergateway.com
27.123.16.117	PTR	tig-net16-117.trueintergateway.com
27.123.16.170	PTR	tig-net16-170.trueintergateway.com
27.123.16.173	PTR	tig-net16-173.trueintergateway.com
27.123.16.174	PTR	tig-net16-174.trueintergateway.com
27.123.16.206	PTR	tig-net16-206.trueintergateway.com
27.123.16.214	PTR	tig-net16-214.trueintergateway.com
27.123.16.251	PTR	tig-net16-251.trueintergateway.com
27.123.17.12	PTR	tig-net17-12.trueintergateway.com
27.123.17.12	A	r1.sn-ug0x-c33s.googlevideo.com
27.123.17.12	A	r1.sn-ug0x-c33s.gvt1.com
27.123.17.13	PTR	tig-net17-13.trueintergateway.com
27.123.17.13	A	r2.sn-ug0x-c33s.googlevideo.com
27.123.17.13	A	r2.sn-ug0x-c33s.gvt1.com
27.123.17.14	PTR	tig-net17-14.trueintergateway.com
27.123.17.15	PTR	tig-net17-15.trueintergateway.com
27.123.17.49	PTR	tig-net17-49.trueintergateway.com
27.123.17.76	PTR	tig-net17-76.trueintergateway.com
27.123.17.78	PTR	tig-net17-78.trueintergateway.com
27.123.17.78	A	r3.sn-ug0x-c33z.googlevideo.com
27.123.17.79	PTR	tig-net17-79.trueintergateway.com
27.123.17.79	A	r4.sn-ug0x-c33z.googlevideo.com
27.123.17.121	PTR	tig-net17-121.trueintergateway.com
27.123.17.145	PTR	tig-net17-145.trueintergateway.com
27.123.17.145	A	external.fbkk2-1.fna.fbcdn.net
27.123.17.145	A	scontent.fbkk2-1.fna.fbcdn.net
27.123.17.146	A	video.fbkk2-1.fna.fbcdn.net
27.123.17.158	PTR	tig-net17-158.trueintergateway.com
27.123.17.158	A	sonar.fbkk2-1.fna.fbcdn.net
27.123.17.158	A	z-m-scontent.fbkk2-1.fna.fbcdn.net
27.123.17.160	PTR	tig-net17-160.trueintergateway.com
27.123.17.160	A	instagram.fbkk2-1.fna.fbcdn.net
27.123.17.162	PTR	tig-net17-162.trueintergateway.com
27.123.17.162	A	z-p3-scontent.fbkk2-1.fna.fbcdn.net
27.123.17.168	PTR	tig-net17-168.trueintergateway.com
27.123.17.168	A	z-1-scontent.fbkk2-1.fna.fbcdn.net
27.123.17.168	A	z-1-external.fbkk2-1.fna.fbcdn.net
27.123.17.209	PTR	tig-net17-209.trueintergateway.com
27.123.17.209	A	scontent.fbkk1-1.fna.fbcdn.net
27.123.17.209	A	external.fbkk1-1.fna.fbcdn.net
27.123.17.210	PTR	tig-net17-210.trueintergateway.com
27.123.17.210	A	video.fbkk1-1.fna.fbcdn.net
27.123.17.222	PTR	tig-net17-222.trueintergateway.com
27.123.17.222	A	sonar.fbkk1-1.fna.fbcdn.net
27.123.17.224	PTR	tig-net17-224.trueintergateway.com
27.123.17.224	A	instagram.fbkk1-1.fna.fbcdn.net
27.123.17.226	PTR	tig-net17-226.trueintergateway.com
27.123.17.226	A	z-p3-scontent.fbkk1-1.fna.fbcdn.net
27.123.17.232	PTR	tig-net17-232.trueintergateway.com
27.123.17.232	A	z-1-scontent.fbkk1-1.fna.fbcdn.net
27.123.17.235	PTR	tig-net17-235.trueintergateway.com
27.123.17.235	A	z-p4-instagram.fbkk1-1.fna.fbcdn.net
27.123.18.81	PTR	tig-net18-81.trueintergateway.com
27.123.18.81	A	scontent.fbkk1-4.fna.fbcdn.net
27.123.18.81	A	external.fbkk1-4.fna.fbcdn.net
27.123.18.82	PTR	tig-net18-82.trueintergateway.com
27.123.18.82	A	scontent.fbkk22-6.fna.fbcdn.net
27.123.18.82	A	video.fbkk1-4.fna.fbcdn.net
27.123.18.94	PTR	tig-net18-94.trueintergateway.com
27.123.18.94	A	sonar.fbkk1-4.fna.fbcdn.net
27.123.18.94	A	z-m-scontent.fbkk1-4.fna.fbcdn.net
27.123.18.96	PTR	tig-net18-96.trueintergateway.com
27.123.18.96	A	instagram.fbkk1-4.fna.fbcdn.net
27.123.18.97	PTR	tig-net18-97.trueintergateway.com
27.123.18.97	A	media.fbkk1-4.fna.whatsapp.net
27.123.18.98	PTR	tig-net18-98.trueintergateway.com
27.123.18.98	A	z-p3-scontent.fbkk1-4.fna.fbcdn.net
27.123.18.104	PTR	tig-net18-104.trueintergateway.com
27.123.18.104	A	z-1-scontent.fbkk1-4.fna.fbcdn.net
27.123.18.107	PTR	tig-net18-107.trueintergateway.com
27.123.18.107	A	z-p4-instagram.fbkk1-4.fna.fbcdn.net
27.123.18.145	PTR	tig-net18-145.trueintergateway.com
27.123.18.145	A	external.fbkk2-4.fna.fbcdn.net
27.123.18.146	PTR	tig-net18-146.trueintergateway.com
27.123.18.146	A	video.fbkk2-4.fna.fbcdn.net
27.123.18.158	PTR	tig-net18-158.trueintergateway.com
27.123.18.158	A	sonar.fbkk2-4.fna.fbcdn.net
27.123.18.158	A	z-p3-sonar.fbkk2-4.fna.fbcdn.net
27.123.18.160	PTR	tig-net18-160.trueintergateway.com
27.123.18.160	A	instagram.fbkk2-4.fna.fbcdn.net
27.123.18.162	PTR	tig-net18-162.trueintergateway.com
27.123.18.162	A	z-p3-scontent.fbkk2-4.fna.fbcdn.net
27.123.18.168	PTR	tig-net18-168.trueintergateway.com
27.123.18.168	A	z-1-scontent.fbkk2-4.fna.fbcdn.net
27.123.18.171	PTR	tig-net18-171.trueintergateway.com
27.123.18.171	A	z-p4-instagram.fbkk2-4.fna.fbcdn.net