Robtex

Up: 157.240.192.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 157.240.193.0/25
Down right: 157.240.193.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
157.240.193.10	A	video-fco1-1.xx.fbcdn.net
157.240.193.10	A	edge-video-shv-01-fco1.fbcdn.net
157.240.193.16	A+PTR	xx-fbcdn-shv-01-fco1.fbcdn.net
157.240.193.16	A	scontent-fco1-1.xx.fbcdn.net
157.240.193.18	A+PTR	edge-star-shv-01-fco1.facebook.com
157.240.193.25	A+PTR	edge-mqtt-shv-01-fco1.facebook.com
157.240.193.35	A	edge-star-mini-shv-01-fco1.facebook.com
157.240.193.36	A+PTR	edge-z-m-mini-shv-01-fco1.facebook.com
157.240.193.38	PTR	edge-sonar-mini-shv-01-fco1.fbcdn.net
157.240.193.38	A	f020a1efb80-fxvtjpoi1547861184-sonar.xx.fbcdn.net
157.240.193.38	A	fb92ee44a80-wxktzght1543769787-sonar.xx.fbcdn.net
157.240.193.48	A+PTR	edgeray-shv-01-fco1.facebook.com
157.240.193.50	A+PTR	whatsapp-cdn-shv-01-fco1.fbcdn.net
157.240.193.50	A	media-fco1-1.cdn.whatsapp.net
157.240.193.53	A+PTR	edge-mws-shv-01-fco1.facebook.com
157.240.193.55	PTR	whatsapp-chatd-edge-shv-01-fco1.facebook.com
157.240.193.63	A+PTR	instagram-p3-shv-01-fco1.fbcdn.net
157.240.193.63	A	scontent-fco1-1.cdninstagram.com
157.240.193.169	A+PTR	edge-z-p4-shv-01-fco1.facebook.com
157.240.193.174	A+PTR	instagram-p42-shv-01-fco1.fbcdn.net