Network ACL Outbound Terraform Module
This Terraform Module launches is a simple helper for adding outbound rules to a Network ACL. Network ACLs can be a bit tricky to work with because they are stateless, which means that opening an outbound port is often not enough; you also need to open ephemeral inbound ports which the remote services can use to respond. This can be very easy to forget, so this module adds not only the outbound to an ACL, but also the ephemeral inbound ports for return traffic.
See the network-acl-inbound module for the analogous version of this module, but for opening inbound ports.
What's a Network ACL?
Network ACLs provide an extra layer of network security, similar to a security group. Whereas a security group controls what inbound and outbound traffic is allowed for a specific resource (e.g. a single EC2 instance), a network ACL controls what inbound and outbound traffic is allowed for an entire subnet.