Robtex

Up: 203.226.64.0/18
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Down left: 203.226.64.0/20
Down right: 203.226.80.0/20

IP	Type	Hostname
203.226.64.13	PTR	ns.doosanheavy.com
203.226.64.13	A	ns.doosanheavy.co.kr
203.226.64.14	PTR	ns1.doosanheavy.com
203.226.64.14	A	ns1.doosanheavy.co.kr
203.226.64.22	A	dhweb.doosanheavy.com
203.226.64.44	A	dhweb.doosanheavy.com
203.226.64.46	A	ns003.doosan.com
203.226.64.52	A	dhjobtrdb.doosanheavy.com
203.226.64.74	A	happytogether.doosanheavy.com
203.226.64.84	A	e-sourcingsbc.doosanheavy.com
203.226.66.171	PTR	sslvpn.doosanheavy.com
203.226.66.171	PTR	vpn.doosanheavy.com
203.226.69.11	A	sfw1.doosanheavy.com
203.226.69.16	PTR	dhusbm.doosanheavy.com