aws_stuff.md

1. Retrieve Security Groups via AWS CLI Get the Security Groups Attached to an Instance Run:

aws ec2 describe-instances --instance-id $(curl -s http://169.254.169.254/latest/meta-data/instance-id) --query "Reservations[].Instances[].SecurityGroups" --output json

This will return something like:

[
  {
    "GroupName": "MySecurityGroup",
    "GroupId": "sg-0a1b2c3d4e5f67890"
  }
]
2. Get Open Ports in the Security Group

Once you have the Security Group ID, check the allowed ports:

sh Copy Edit aws ec2 describe-security-groups --group-ids sg-0a1b2c3d4e5f67890 --query "SecurityGroups[].IpPermissions" Example output:

json Copy Edit [ { "IpProtocol": "tcp", "FromPort": 22, "ToPort": 22, "IpRanges": [{"CidrIp": "0.0.0.0/0"}] }, { "IpProtocol": "tcp", "FromPort": 80, "ToPort": 80, "IpRanges": [{"CidrIp": "0.0.0.0/0"}] } ] This means ports 22 (SSH) and 80 (HTTP) are open to the internet.

3. Automate Everything in One Command sh Copy Edit aws ec2 describe-security-groups --group-ids $(aws ec2 describe-instances --instance-id $(curl -s http://169.254.169.254/latest/meta-data/instance-id) --query "Reservations[].Instances[].SecurityGroups[].GroupId" --output text) --query "SecurityGroups[].IpPermissions" This retrieves the instance’s Security Group(s) and lists open ports in one go.