Robtex

Up: 45.58.64.0/19
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Down left: 45.58.64.0/21
Down right: 45.58.72.0/21
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
45.58.66.77	PTR	ae13-iad2-dr02.net.dropbox.com
45.58.66.104	PTR	ae19-iad7-bb01.net.dropbox.com
45.58.69.1	A	dl-client94.dropbox.com
45.58.69.1	A	dl-client17.dropbox.com
45.58.69.1	A	dl-client113.dropbox.com
45.58.69.33	A	dl-client8.dropbox.com
45.58.69.33	A	edge-block-client-fallback.dropbox-dns.com
45.58.69.38	A	block-misc.g1.dropbox.com
45.58.69.65	A	dl-client86.dropbox.com
45.58.69.65	A	dl-client123.dropbox.com
45.58.69.65	A	dl-client55.dropbox.com
45.58.69.97	A	dl-client94.dropbox.com
45.58.69.97	A	dl-client17.dropbox.com
45.58.69.97	A	dl-client113.dropbox.com
45.58.70.1	A	dl-client17.dropbox.com
45.58.70.1	A	dl-client113.dropbox.com
45.58.70.1	A	dl-client79.dropbox.com
45.58.70.33	A	edge-block-client-fallback.dropbox-dns.com
45.58.70.33	A	dl-client23.dropbox.com
45.58.70.33	A	dl-client66.dropbox.com
45.58.71.46	A	iad4c-ra2-7c.sjc.dropbox.com
45.58.71.46	A	gw.pp.dropbox.com
45.58.71.106	A	iad4c-rc2-9c.sjc.dropbox.com
45.58.74.1	A	dl-client94.dropbox.com
45.58.74.1	A	dl-client17.dropbox.com
45.58.74.1	A	dl-client113.dropbox.com
45.58.74.33	A	block-iad.dropbox-dns.com
45.58.74.33	A	dl-client23.dropbox.com
45.58.74.33	A	dl-client66.dropbox.com
45.58.74.129	A	dl-client94.dropbox.com
45.58.74.129	A	dl-client17.dropbox.com
45.58.74.129	A	dl-client113.dropbox.com
45.58.74.161	A	dl-client8.dropbox.com
45.58.74.161	A	dl-client86.dropbox.com
45.58.74.161	A	dl-client123.dropbox.com
45.58.75.164	A	block-api-dfw.dropbox-dns.com
45.58.75.165	A	block-www-dfw.dropbox-dns.com
45.58.76.36	PTR	ae12-dfw1-bb02.net.dropbox.com
45.58.76.45	PTR	ae14-dfw3-dr01.net.dropbox.com