IPv6 instances in a VPC must reach the internet outbound but NOT be reachable inbound — the IPv6 equivalent of a NAT gateway. Which component does this?
A.NAT64 gateway
NAT64 translates IPv6→IPv4 — different problem.
B.Egress-only internet gateway (EIGW)
Correct. Outbound-initiated only for IPv6.
C.A second internet gateway
A plain IGW allows bidirectional public reachability.
D.NAT gateway configured for IPv6
NAT gateways don't do IPv6 outbound-only semantics.
Why this answer
Egress-only IGW is the IPv6 outbound-only device — allows return traffic for initiated connections while blocking inbound initiation. NAT gateways are IPv4 constructs; IPv6 has no address scarcity to hide behind.
Correct answer: B · Last reviewed 2026-11-04
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