Robtex

Up: 2620:100:9000::/45
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Down left: 2620:100:9000::/47
Down right: 2620:100:9002::/47

IP	Type	Hostname
2620:100:9000::32	A+PTR	ns-sc4.proofpoint.com
2620:100:9000::32	A+PTR	ns-sc4.proofpoint.us
2620:100:9000:1::d0	A+PTR	ns1.proofpoint.com
2620:100:9000:1::d0	A	ns1.proofpoint.us
2620:100:9001:13::1	A	mx0a-0007e701.pphosted.com
2620:100:9001:13::1	A	mx1.clickbooq.com.gslb.pphosted.com
2620:100:9001:13::1	A	mx2.clickbooq.com.gslb.pphosted.com
2620:100:9001:15::1	A+PTR	mx0a-00206401.pphosted.com
2620:100:9001:5b::1	PTR	mx0a-0020ca01.pphosted.com
2620:100:9001:5e::1	PTR	mx0a-000cb501.pphosted.com
2620:100:9001:583::1	A+PTR	mx0a-00190b01.pphosted.com
2620:100:9001:58e::1	A+PTR	mx0a-00192d01.pphosted.com
2620:100:9001:5bd::1	A+PTR	mx0a-000cda019.pphosted.com
2620:100:9001:801::1	A+PTR	mx0a-0013cc01.pphosted.com