FTD Anyconnect with DHCP server for address assignment

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 1. Anyconnect DHCP configuration in FMC



























this is a host object, can be .0 or any number in the scope.























2. Packet capture on DHCP server 

DHCP discover packet is unicast

























DHCP offer is unicast to DHCP replay IP, not FW IP.



















































































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This article says IP-Helper address is required when DHCP server is not on the same subnet with FTD inside interface, but since DHCP packets we saw above are unicast, IP-Helper address shouldn't be required.
 
https://www.cisco.com/c/en/us/support/docs/security/anyconnect-secure-mobility-client/215854-configure-anyconnect-vpn-client-on-ftd.pdf

Case:
AC client didn't receive IP address, capture on DHCP server had the repeated DHCP Discover and Offer packets , packet tracer showed  DHCP offer hit a NAT rule then was sent to outside interface, found the exemption NAT is missing route-lookup keyword caused the DHCP offer wasn't processed as expected .

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