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#ports

Port ranges in AWS networking, including the ephemeral range a network ACL has to allow outbound before an inbound connection can ever complete.

1 article tagged #ports, newest first.

August 21, 2026
Ephemeral Ports and the Network ACL Rule Everyone Forgets
Security groups are stateful, network ACLs are not. A NACL allowing inbound 443 but not outbound 1024-65535 lets a connection start, then kills it.