Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

Creating, configuring, and deleting security groups for Amazon EC2

You can create a security group for your Amazon Elastic Compute Cloud (Amazon EC2) instances that essentially operates as a firewall, with rules that determine what network traffic can enter and leave.

Use the Amazon Command Line Interface (Amazon CLI) to create a security group, add rules to existing security groups, and delete security groups.

Prerequisites

To run the ec2 commands, you need to:

Create a security group

You can create security groups associated with virtual private clouds (VPCs) .

The following aws ec2 create-security-group example shows how to create a security group for a specified VPC.

$ aws ec2 create-security-group --group-name my-sg --description "My security group" --vpc-id vpc-1a2b3c4d
{
    "GroupId": "sg-903004f8"
}

To view the initial information for a security group, run the aws ec2 describe-security-groups command. You can reference an EC2-VPC security group only by its vpc-id, not its name.

$ aws ec2 describe-security-groups --group-ids sg-903004f8
{
    "SecurityGroups": [
        {
            "IpPermissionsEgress": [
                {
                    "IpProtocol": "-1",
                    "IpRanges": [
                        {
                            "CidrIp": "0.0.0.0/0"
                        }
                    ],
                    "UserIdGroupPairs": []
                }
            ],
            "Description": "My security group"
            "IpPermissions": [],
            "GroupName": "my-sg",
            "VpcId": "vpc-1a2b3c4d",
            "OwnerId": "123456789012",
            "GroupId": "sg-903004f8"
        }
    ]
}

Add rules to your security group

When you run an Amazon EC2 instance, you must enable rules in the security group to allow incoming network traffic for your means of connecting to the image.

For example, if you're launching a Windows instance, you typically add a rule to allow inbound traffic on TCP port 3389 to support Remote Desktop Protocol (RDP). If you're launching a Linux instance, you typically add a rule to allow inbound traffic on TCP port 22 to support SSH connections.

Use the aws ec2 authorize-security-group-ingress command to add a rule to your security group. A required parameter of this command is the public IP address of your computer, or the network (in the form of an address range) that your computer is attached to, in CIDR notation.

The following example shows how to add a rule for RDP (TCP port 3389) to an EC2-VPC security group with the ID sg-903004f8 using your IP address.

To start, find your IP address.

$ curl https://checkip.amazonaws.com
x.x.x.x

You can then add the IP address to your security group by running the aws ec2 authorize-security-group-ingress command.

$ aws ec2 authorize-security-group-ingress --group-id sg-903004f8 --protocol tcp --port 3389 --cidr x.x.x.x/x

The following command adds another rule to enable SSH to instances in the same security group.

$ aws ec2 authorize-security-group-ingress --group-id sg-903004f8 --protocol tcp --port 22 --cidr x.x.x.x/x

To view the changes to the security group, run the aws ec2 describe-security-groups command.

$ aws ec2 describe-security-groups --group-ids sg-903004f8
{
    "SecurityGroups": [
        {
            "IpPermissionsEgress": [
                {
                    "IpProtocol": "-1",
                    "IpRanges": [
                        {
                            "CidrIp": "0.0.0.0/0"
                        }
                    ],
                    "UserIdGroupPairs": []
                }
            ],
            "Description": "My security group"
            "IpPermissions": [
                {
                    "ToPort": 22,
                    "IpProtocol": "tcp",
                    "IpRanges": [
                        {
                            "CidrIp": "x.x.x.x/x"
                        }
                    ]
                    "UserIdGroupPairs": [],
                    "FromPort": 22
                }
            ],
            "GroupName": "my-sg",
            "OwnerId": "123456789012",
            "GroupId": "sg-903004f8"
        }
    ]
}

Delete your security group

To delete a security group, run the aws ec2 delete-security-group command.

The following command example deletes an EC2-VPC security group.

$ aws ec2 delete-security-group --group-id sg-903004f8

References

Amazon CLI reference:

Other reference: