This Terraform Module launches is a simple helper for adding inbound rules to a Network
ACL. Network ACLs can be a bit tricky to work
with because they are stateless, which means that opening an inbound port is often not enough; you also need to open
ephemeral outbound ports
which your services use to respond. This can be very easy to forget, so this module adds not only the inbound ports to
an ACL, but also the ephemeral outbound ports for return traffic.
See the network-acl-outbound module for the analogous version of this module, but for opening
outbound ports.
Check out vars.tf for all the configuration options available.
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.
Questions? Ask away.
We're here to talk about our services, answer any questions, give advice, or just to chat.
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class=\"preview__body--title\" id=\"network-acl-inbound-terraform-module\">Network ACL Inbound Terraform Module</h1><div class=\"preview__body--border\"></div><p>This Terraform Module launches is a simple helper for adding inbound rules to a <a href=\"http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_ACLs.html\" class=\"preview__body--description--blue\" target=\"_blank\">Network\nACL</a>. Network ACLs can be a bit tricky to work\nwith because they are stateless, which means that opening an inbound port is often not enough; you also need to open\n<a href=\"http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_ACLs.html#VPC_ACLs_Ephemeral_Ports\" class=\"preview__body--description--blue\" target=\"_blank\">ephemeral outbound ports</a>\nwhich your services use to respond. This can be very easy to forget, so this module adds not only the inbound ports to\nan ACL, but also the ephemeral outbound ports for return traffic.</p>\n<p>See the <a href=\"/repos/v0.10.1/terraform-aws-vpc/modules/network-acl-outbound\" class=\"preview__body--description--blue\">network-acl-outbound</a> module for the analogous version of this module, but for opening\noutbound ports.</p>\n<h2 class=\"preview__body--subtitle\" id=\"how-do-you-use-this-module\">How do you use this module?</h2>\n<p>Check out the <a href=\"/repos/v0.10.1/terraform-aws-vpc/modules/vpc-app-network-acls\" class=\"preview__body--description--blue\">vpc-app-network-acls</a> and\n<a href=\"/repos/v0.10.1/terraform-aws-vpc/modules/vpc-mgmt-network-acls\" class=\"preview__body--description--blue\">vpc-mgmt-network-acls</a> modules for examples.</p>\n<p>Check out <a href=\"/repos/v0.10.1/terraform-aws-vpc/modules/network-acl-inbound/vars.tf\" class=\"preview__body--description--blue\">vars.tf</a> for all the configuration options available.</p>\n<h2 class=\"preview__body--subtitle\" id=\"whats-a-network-acl\">What's a Network ACL?</h2>\n<p><a href=\"http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_ACLs.html\" class=\"preview__body--description--blue\" target=\"_blank\">Network ACLs</a> provide an extra layer of network\nsecurity, similar to a <a href=\"http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-network-security.html\" class=\"preview__body--description--blue\" target=\"_blank\">security group</a>.\nWhereas a security group controls what inbound and outbound traffic is allowed for a specific resource (e.g. a single\nEC2 instance), a network ACL controls what inbound and outbound traffic is allowed for an entire subnet.</p>\n","repoName":"terraform-aws-vpc","repoRef":"v0.11.0","serviceDescriptor":{"serviceName":"Virtual Private Cloud (VPC)","serviceRepoName":"terraform-aws-vpc","serviceRepoOrg":"gruntwork-io","cloudProviders":["aws"],"description":"Create a Virtual Private Cloud (VPC). Includes multiple subnet tiers, NACLs, NAT gateways, Internet Gateways, and VPC peering.","imageUrl":"vpc.png","licenseType":"subscriber","technologies":["Terraform"],"compliance":[],"tags":[""]},"serviceCategoryName":"Networking","fileName":"README.md","filePath":"/modules/network-acl-inbound","title":"Repo Browser: Virtual Private Cloud (VPC)","description":"Browse the repos in the Gruntwork Infrastructure as Code Library."}