Symptom
Two interfaces configured in a single ZONE drops ICMP flow with no-adjacency while performing lookup of egress interface for ICMP reply packet. If any ICMP request packet is received on Interface-1 configured in a zone and the reply packet for that ICMP request is tried to be sent out via Interface-2 in the same zone then it gets dropped on the ASA due to "no-valid-adjacency".
Conditions
Interface configured in zone and have dynamic routing enabled where preferred route to forward the flow is via one of the specific interface in the zone.
