Using Client Subnet in DNS Requests
BIG-IP DNS 14.0 now supports edns-client-subnet (ECS) for both responding to client requests (GSLB) or forwarding client requests (screening). The following is a quick start on using this feature.
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Published Sep 14, 2018
Version 1.0
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Nimbostratus
NimbostratusEric Chen wrote this article based on the GUI features available in 14, however in version 13 ECS was available as a feature to be used within an irule. Eric’s previous article which was based on v13 has some iRules examples that you could use as your starting point. https://devcentral.f5.com/s/articles/implementing-client-subnet-dns-requests