├── endpoints.tf ├── routes.tf ├── asg.tf ├── outputs.tf ├── launch_template.tf ├── security_group.tf ├── README.md ├── variables.tf └── LICENSE /endpoints.tf: -------------------------------------------------------------------------------- 1 | resource "aws_vpc_endpoint" "s3" { 2 | count = local.s3_endpoint 3 | vpc_id = local.vpc_id 4 | service_name = "com.amazonaws.${data.aws_region.current.name}.s3" 5 | auto_accept = true 6 | route_table_ids = [aws_route_table.nat.id] 7 | tags = local.tags 8 | } 9 | -------------------------------------------------------------------------------- /routes.tf: -------------------------------------------------------------------------------- 1 | resource "aws_route_table" "nat" { 2 | vpc_id = local.vpc_id 3 | tags = local.tags 4 | } 5 | 6 | resource "aws_route" "internet" { 7 | count = local.internet_route 8 | route_table_id = aws_route_table.nat.id 9 | destination_cidr_block = "0.0.0.0/0" 10 | network_interface_id = aws_network_interface.nat.id 11 | } 12 | -------------------------------------------------------------------------------- /asg.tf: -------------------------------------------------------------------------------- 1 | resource "aws_autoscaling_group" "nat_instance" { 2 | name_prefix = local.name 3 | desired_capacity = 1 4 | max_size = 1 5 | min_size = 1 6 | availability_zones = [local.az] 7 | 8 | launch_template { 9 | id = aws_launch_template.nat_instance.id 10 | version = aws_launch_template.nat_instance.latest_version 11 | } 12 | } 13 | -------------------------------------------------------------------------------- /outputs.tf: -------------------------------------------------------------------------------- 1 | output "route_table_id" { 2 | value = aws_route_table.nat.id 3 | } 4 | 5 | output "eip" { 6 | value = aws_eip.public_ip.public_ip 7 | } 8 | 9 | output "security_group_arn" { 10 | value = aws_security_group.nat.arn 11 | } 12 | 13 | output "security_group_id" { 14 | value = aws_security_group.nat.id 15 | } 16 | 17 | output "network_interface_id" { 18 | value = aws_network_interface.nat.id 19 | } 20 | -------------------------------------------------------------------------------- /launch_template.tf: -------------------------------------------------------------------------------- 1 | resource "aws_network_interface" "nat" { 2 | subnet_id = local.nat_subnet_id 3 | source_dest_check = false 4 | security_groups = [aws_security_group.nat.id] 5 | tags = local.tags 6 | } 7 | 8 | resource "aws_eip" "public_ip" { 9 | network_interface = aws_network_interface.nat.id 10 | tags = local.tags 11 | } 12 | 13 | resource "aws_launch_template" "nat_instance" { 14 | name_prefix = local.name 15 | image_id = local.ami 16 | instance_type = local.instance_type 17 | tags = local.tags 18 | 19 | network_interfaces { 20 | device_index = 0 21 | network_interface_id = aws_network_interface.nat.id 22 | } 23 | 24 | tag_specifications { 25 | resource_type = "instance" 26 | tags = local.tags 27 | } 28 | } 29 | -------------------------------------------------------------------------------- /security_group.tf: -------------------------------------------------------------------------------- 1 | resource "aws_security_group" "nat" { 2 | name_prefix = "NatAz${title(substr(local.az, -1, -1))}" 3 | description = "Rules for Nat instance" 4 | vpc_id = local.vpc_id 5 | tags = local.tags 6 | 7 | dynamic "ingress" { 8 | for_each = local.ports.tcp 9 | content { 10 | cidr_blocks = local.client_subnet_cidrs 11 | from_port = ingress.value 12 | protocol = "tcp" 13 | to_port = ingress.value 14 | } 15 | } 16 | 17 | dynamic "egress" { 18 | for_each = local.ports.tcp 19 | content { 20 | cidr_blocks = ["0.0.0.0/0"] 21 | from_port = egress.value 22 | protocol = "tcp" 23 | to_port = egress.value 24 | } 25 | } 26 | 27 | dynamic "ingress" { 28 | for_each = local.ports.udp 29 | content { 30 | cidr_blocks = local.client_subnet_cidrs 31 | from_port = ingress.value 32 | protocol = "udp" 33 | to_port = ingress.value 34 | } 35 | } 36 | 37 | dynamic "egress" { 38 | for_each = local.ports.udp 39 | content { 40 | cidr_blocks = ["0.0.0.0/0"] 41 | from_port = egress.value 42 | protocol = "udp" 43 | to_port = egress.value 44 | } 45 | } 46 | 47 | lifecycle { 48 | create_before_destroy = true 49 | } 50 | } 51 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | ## About 2 | Terraform module to create NAT instance. The module provides: 3 | 4 | * NAT instance security group with rules allowed 443 port by default 5 | * VPC S3 Logs endpoints to avoid passing internal traffic through NAT 6 | 7 | ## Usage 8 | 9 | ```hcl 10 | module "nat" { 11 | source = "github.com/jetbrains-infra/terraform-aws-nat-instance?ref=vX.X.X" // https://github.com/jetbrains-infra/terraform-aws-routed-subnet/releases/latest 12 | subnet_id = local.subnet_id 13 | public_subnet_id = modules.public_subnet.id // see https://github.com/jetbrains-infra/terraform-aws-routed-subnet 14 | private_subnet_cidrs = [modules.private_subnet.cidr] 15 | ports = [443, 3306] 16 | } 17 | ``` 18 | 19 | Default values 20 | ```hcl 21 | module "nat" { 22 | source = "github.com/jetbrains-infra/terraform-aws-nat-instance?ref=vX.X.X" // https://github.com/jetbrains-infra/terraform-aws-routed-subnet/releases/latest 23 | name = "NatInstance" 24 | subnet_id = local.subnet_id 25 | instance_type = "t3a.small" 26 | public_subnet_id = modules.public_subnet.id // see https://github.com/jetbrains-infra/terraform-aws-routed-subnet 27 | private_subnet_cidrs = [modules.private_subnet.cidr] 28 | ports = [443, 53] 29 | } 30 | ``` 31 | 32 | ## Outputs 33 | 34 | * `route_table_id` - route table id 35 | * `eip` - public IP address of NAT instance 36 | * `security_group_arn` - ARN of NAT instance security group 37 | * `security_group_id` - ID of NAT instance security group 38 | -------------------------------------------------------------------------------- /variables.tf: -------------------------------------------------------------------------------- 1 | variable "name" { 2 | default = "NatInstance" 3 | } 4 | variable "tags" { 5 | description = "Tags." 6 | type = map(string) 7 | default = {} 8 | } 9 | variable "nat_subnet_id" {} 10 | variable "instance_type" { 11 | default = "t3a.small" 12 | } 13 | variable "client_subnet_cidrs" { 14 | type = list(string) 15 | } 16 | variable "ports" { 17 | description = "List of ports allowed to connect from your VPC." 18 | type = object({ 19 | tcp = list(number), 20 | udp = list(number), 21 | }) 22 | default = { 23 | tcp = [443] 24 | udp = [] 25 | } 26 | } 27 | variable "ami" { 28 | default = "" 29 | } 30 | variable "internet_access" { 31 | default = true 32 | } 33 | variable "s3_endpoint" { 34 | default = false 35 | } 36 | data "aws_ami" "nat" { 37 | count = var.ami == "" ? 1 : 0 38 | most_recent = true 39 | owners = ["amazon"] 40 | 41 | filter { 42 | name = "name" 43 | values = ["amzn-ami-vpc-nat*"] 44 | } 45 | } 46 | data "aws_subnet" "nat" { 47 | id = local.nat_subnet_id 48 | } 49 | data "aws_region" "current" {} 50 | 51 | locals { 52 | name = var.name 53 | vpc_id = data.aws_subnet.nat.vpc_id 54 | instance_type = var.instance_type 55 | nat_subnet_id = var.nat_subnet_id 56 | client_subnet_cidrs = var.client_subnet_cidrs 57 | az = data.aws_subnet.nat.availability_zone 58 | ports = var.ports 59 | ami = var.ami == "" ? data.aws_ami.nat[length(data.aws_ami.nat)].id : var.ami 60 | internet_route = var.internet_access == true ? 1 : 0 61 | s3_endpoint = var.s3_endpoint == true ? 1 : 0 62 | tags = merge({ 63 | Name = local.name 64 | Module = "Nat Instance" 65 | ModuleSource = "https://github.com/jetbrains-infra/terraform-aws-nat-instance/" 66 | }, var.tags) 67 | } -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Apache License 2 | Version 2.0, January 2004 3 | http://www.apache.org/licenses/ 4 | 5 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 6 | 7 | 1. Definitions. 8 | 9 | "License" shall mean the terms and conditions for use, reproduction, 10 | and distribution as defined by Sections 1 through 9 of this document. 11 | 12 | "Licensor" shall mean the copyright owner or entity authorized by 13 | the copyright owner that is granting the License. 14 | 15 | "Legal Entity" shall mean the union of the acting entity and all 16 | other entities that control, are controlled by, or are under common 17 | control with that entity. For the purposes of this definition, 18 | "control" means (i) the power, direct or indirect, to cause the 19 | direction or management of such entity, whether by contract or 20 | otherwise, or (ii) ownership of fifty percent (50%) or more of the 21 | outstanding shares, or (iii) beneficial ownership of such entity. 22 | 23 | "You" (or "Your") shall mean an individual or Legal Entity 24 | exercising permissions granted by this License. 25 | 26 | "Source" form shall mean the preferred form for making modifications, 27 | including but not limited to software source code, documentation 28 | source, and configuration files. 29 | 30 | "Object" form shall mean any form resulting from mechanical 31 | transformation or translation of a Source form, including but 32 | not limited to compiled object code, generated documentation, 33 | and conversions to other media types. 34 | 35 | "Work" shall mean the work of authorship, whether in Source or 36 | Object form, made available under the License, as indicated by a 37 | copyright notice that is included in or attached to the work 38 | (an example is provided in the Appendix below). 39 | 40 | "Derivative Works" shall mean any work, whether in Source or Object 41 | form, that is based on (or derived from) the Work and for which the 42 | editorial revisions, annotations, elaborations, or other modifications 43 | represent, as a whole, an original work of authorship. For the purposes 44 | of this License, Derivative Works shall not include works that remain 45 | separable from, or merely link (or bind by name) to the interfaces of, 46 | the Work and Derivative Works thereof. 47 | 48 | "Contribution" shall mean any work of authorship, including 49 | the original version of the Work and any modifications or additions 50 | to that Work or Derivative Works thereof, that is intentionally 51 | submitted to Licensor for inclusion in the Work by the copyright owner 52 | or by an individual or Legal Entity authorized to submit on behalf of 53 | the copyright owner. For the purposes of this definition, "submitted" 54 | means any form of electronic, verbal, or written communication sent 55 | to the Licensor or its representatives, including but not limited to 56 | communication on electronic mailing lists, source code control systems, 57 | and issue tracking systems that are managed by, or on behalf of, the 58 | Licensor for the purpose of discussing and improving the Work, but 59 | excluding communication that is conspicuously marked or otherwise 60 | designated in writing by the copyright owner as "Not a Contribution." 61 | 62 | "Contributor" shall mean Licensor and any individual or Legal Entity 63 | on behalf of whom a Contribution has been received by Licensor and 64 | subsequently incorporated within the Work. 65 | 66 | 2. Grant of Copyright License. Subject to the terms and conditions of 67 | this License, each Contributor hereby grants to You a perpetual, 68 | worldwide, non-exclusive, no-charge, royalty-free, irrevocable 69 | copyright license to reproduce, prepare Derivative Works of, 70 | publicly display, publicly perform, sublicense, and distribute the 71 | Work and such Derivative Works in Source or Object form. 72 | 73 | 3. Grant of Patent License. Subject to the terms and conditions of 74 | this License, each Contributor hereby grants to You a perpetual, 75 | worldwide, non-exclusive, no-charge, royalty-free, irrevocable 76 | (except as stated in this section) patent license to make, have made, 77 | use, offer to sell, sell, import, and otherwise transfer the Work, 78 | where such license applies only to those patent claims licensable 79 | by such Contributor that are necessarily infringed by their 80 | Contribution(s) alone or by combination of their Contribution(s) 81 | with the Work to which such Contribution(s) was submitted. If You 82 | institute patent litigation against any entity (including a 83 | cross-claim or counterclaim in a lawsuit) alleging that the Work 84 | or a Contribution incorporated within the Work constitutes direct 85 | or contributory patent infringement, then any patent licenses 86 | granted to You under this License for that Work shall terminate 87 | as of the date such litigation is filed. 88 | 89 | 4. Redistribution. You may reproduce and distribute copies of the 90 | Work or Derivative Works thereof in any medium, with or without 91 | modifications, and in Source or Object form, provided that You 92 | meet the following conditions: 93 | 94 | (a) You must give any other recipients of the Work or 95 | Derivative Works a copy of this License; and 96 | 97 | (b) You must cause any modified files to carry prominent notices 98 | stating that You changed the files; and 99 | 100 | (c) You must retain, in the Source form of any Derivative Works 101 | that You distribute, all copyright, patent, trademark, and 102 | attribution notices from the Source form of the Work, 103 | excluding those notices that do not pertain to any part of 104 | the Derivative Works; and 105 | 106 | (d) If the Work includes a "NOTICE" text file as part of its 107 | distribution, then any Derivative Works that You distribute must 108 | include a readable copy of the attribution notices contained 109 | within such NOTICE file, excluding those notices that do not 110 | pertain to any part of the Derivative Works, in at least one 111 | of the following places: within a NOTICE text file distributed 112 | as part of the Derivative Works; within the Source form or 113 | documentation, if provided along with the Derivative Works; or, 114 | within a display generated by the Derivative Works, if and 115 | wherever such third-party notices normally appear. The contents 116 | of the NOTICE file are for informational purposes only and 117 | do not modify the License. You may add Your own attribution 118 | notices within Derivative Works that You distribute, alongside 119 | or as an addendum to the NOTICE text from the Work, provided 120 | that such additional attribution notices cannot be construed 121 | as modifying the License. 122 | 123 | You may add Your own copyright statement to Your modifications and 124 | may provide additional or different license terms and conditions 125 | for use, reproduction, or distribution of Your modifications, or 126 | for any such Derivative Works as a whole, provided Your use, 127 | reproduction, and distribution of the Work otherwise complies with 128 | the conditions stated in this License. 129 | 130 | 5. Submission of Contributions. Unless You explicitly state otherwise, 131 | any Contribution intentionally submitted for inclusion in the Work 132 | by You to the Licensor shall be under the terms and conditions of 133 | this License, without any additional terms or conditions. 134 | Notwithstanding the above, nothing herein shall supersede or modify 135 | the terms of any separate license agreement you may have executed 136 | with Licensor regarding such Contributions. 137 | 138 | 6. Trademarks. This License does not grant permission to use the trade 139 | names, trademarks, service marks, or product names of the Licensor, 140 | except as required for reasonable and customary use in describing the 141 | origin of the Work and reproducing the content of the NOTICE file. 142 | 143 | 7. Disclaimer of Warranty. Unless required by applicable law or 144 | agreed to in writing, Licensor provides the Work (and each 145 | Contributor provides its Contributions) on an "AS IS" BASIS, 146 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or 147 | implied, including, without limitation, any warranties or conditions 148 | of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A 149 | PARTICULAR PURPOSE. You are solely responsible for determining the 150 | appropriateness of using or redistributing the Work and assume any 151 | risks associated with Your exercise of permissions under this License. 152 | 153 | 8. Limitation of Liability. In no event and under no legal theory, 154 | whether in tort (including negligence), contract, or otherwise, 155 | unless required by applicable law (such as deliberate and grossly 156 | negligent acts) or agreed to in writing, shall any Contributor be 157 | liable to You for damages, including any direct, indirect, special, 158 | incidental, or consequential damages of any character arising as a 159 | result of this License or out of the use or inability to use the 160 | Work (including but not limited to damages for loss of goodwill, 161 | work stoppage, computer failure or malfunction, or any and all 162 | other commercial damages or losses), even if such Contributor 163 | has been advised of the possibility of such damages. 164 | 165 | 9. Accepting Warranty or Additional Liability. While redistributing 166 | the Work or Derivative Works thereof, You may choose to offer, 167 | and charge a fee for, acceptance of support, warranty, indemnity, 168 | or other liability obligations and/or rights consistent with this 169 | License. However, in accepting such obligations, You may act only 170 | on Your own behalf and on Your sole responsibility, not on behalf 171 | of any other Contributor, and only if You agree to indemnify, 172 | defend, and hold each Contributor harmless for any liability 173 | incurred by, or claims asserted against, such Contributor by reason 174 | of your accepting any such warranty or additional liability. 175 | 176 | END OF TERMS AND CONDITIONS 177 | 178 | APPENDIX: How to apply the Apache License to your work. 179 | 180 | To apply the Apache License to your work, attach the following 181 | boilerplate notice, with the fields enclosed by brackets "[]" 182 | replaced with your own identifying information. (Don't include 183 | the brackets!) The text should be enclosed in the appropriate 184 | comment syntax for the file format. We also recommend that a 185 | file or class name and description of purpose be included on the 186 | same "printed page" as the copyright notice for easier 187 | identification within third-party archives. 188 | 189 | Copyright [yyyy] [name of copyright owner] 190 | 191 | Licensed under the Apache License, Version 2.0 (the "License"); 192 | you may not use this file except in compliance with the License. 193 | You may obtain a copy of the License at 194 | 195 | http://www.apache.org/licenses/LICENSE-2.0 196 | 197 | Unless required by applicable law or agreed to in writing, software 198 | distributed under the License is distributed on an "AS IS" BASIS, 199 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 200 | See the License for the specific language governing permissions and 201 | limitations under the License. 202 | --------------------------------------------------------------------------------