aws_security_group

Provides a security group resource.

~> NOTE on Security Groups and Security Group Rules: Terraform currently provides both a standalone Security Group Rule resource (a single ingress or egress rule), and a Security Group resource with ingress and egress rules defined in-line. At this time you cannot use a Security Group with in-line rules in conjunction with any Security Group Rule resources. Doing so will cause a conflict of rule settings and will overwrite rules.

Example Usage

Basic usage

resource "aws_security_group" "allow_all" {
  name = "allow_all"
  description = "Allow all inbound traffic"

  ingress {
      from_port = 0
      to_port = 0
      protocol = "-1"
      cidr_blocks = ["0.0.0.0/0"]
  }

  egress {
      from_port = 0
      to_port = 0
      protocol = "-1"
      cidr_blocks = ["0.0.0.0/0"]
      prefix_list_ids = ["pl-12c4e678"]
  }
}

Basic usage with tags:

resource "aws_security_group" "allow_all" {
  name = "allow_all"
  description = "Allow all inbound traffic"

  ingress {
      from_port = 0
      to_port = 65535
      protocol = "tcp"
      cidr_blocks = ["0.0.0.0/0"]
  }

  tags {
    Name = "allow_all"
  }
}

Argument Reference

The following arguments are supported:

  • name - (Optional, Forces new resource) The name of the security group. If omitted, Terraform will assign a random, unique name
  • name_prefix - (Optional, Forces new resource) Creates a unique name beginning with the specified prefix. Conflicts with name.
  • description - (Optional, Forces new resource) The security group description. Defaults to "Managed by Terraform". Cannot be "". NOTE: This field maps to the AWS GroupDescription attribute, for which there is no Update API. If you'd like to classify your security groups in a way that can be updated, use tags.
  • ingress - (Optional) Can be specified multiple times for each ingress rule. Each ingress block supports fields documented below.
  • egress - (Optional, VPC only) Can be specified multiple times for each
    egress rule. Each egress block supports fields documented below.
    
  • vpc_id - (Optional, Forces new resource) The VPC ID.
  • tags - (Optional) A mapping of tags to assign to the resource.

The ingress block supports:

  • cidr_blocks - (Optional) List of CIDR blocks.
  • from_port - (Required) The start port (or ICMP type number if protocol is "icmp")
  • protocol - (Required) The protocol. If you select a protocol of "-1", you must specify a "from_port" and "to_port" equal to 0.
  • security_groups - (Optional) List of security group Group Names if using EC2-Classic, or Group IDs if using a VPC.
  • self - (Optional) If true, the security group itself will be added as a source to this ingress rule.
  • to_port - (Required) The end range port (or ICMP code if protocol is "icmp").

The egress block supports:

  • cidr_blocks - (Optional) List of CIDR blocks.
  • prefix_list_ids - (Optional) List of prefix list IDs (for allowing access to VPC endpoints)
  • from_port - (Required) The start port (or ICMP type number if protocol is "icmp")
  • protocol - (Required) The protocol. If you select a protocol of "-1", you must specify a "from_port" and "to_port" equal to 0.
  • security_groups - (Optional) List of security group Group Names if using EC2-Classic, or Group IDs if using a VPC.
  • self - (Optional) If true, the security group itself will be added as a source to this egress rule.
  • to_port - (Required) The end range port (or ICMP code if protocol is "icmp").

~> NOTE on Egress rules: By default, AWS creates an ALLOW ALL egress rule when creating a new Security Group inside of a VPC. When creating a new Security Group inside a VPC, Terraform will remove this default rule, and require you specifically re-create it if you desire that rule. We feel this leads to fewer surprises in terms of controlling your egress rules. If you desire this rule to be in place, you can use this egress block:

egress {
  from_port = 0
  to_port = 0
  protocol = "-1"
  cidr_blocks = ["0.0.0.0/0"]
}

Usage with prefix list IDs

Prefix list IDs are manged by AWS internally. Prefix list IDs are associated with a prefix list name, or service name, that is linked to a specific region. Prefix list IDs are exported on VPC Endpoints, so you can use this format:

    ...
      egress {
        from_port = 0
        to_port = 0
        protocol = "-1"
        prefix_list_ids = ["${aws_vpc_endpoint.my_endpoint.prefix_list_id}"]
      }
    ...
    resource "aws_vpc_endpoint" "my_endpoint" {
      ...
    }

Attributes Reference

The following attributes are exported:

  • id - The ID of the security group
  • vpc_id - The VPC ID.
  • owner_id - The owner ID.
  • name - The name of the security group
  • description - The description of the security group
  • ingress - The ingress rules. See above for more.
  • egress - The egress rules. See above for more.

Import

Security Groups can be imported using the security group id, e.g.

$ terraform import aws_security_group.elb_sg sg-903004f8