The IP address
169.254.169.254 is a link-local address used by cloud environments, including Google Cloud Platform (GCP), Amazon Web Services (AWS), and others. This IP address is used to provide metadata to instances running in the cloud environment.
If you run the
ip route command, you will see the following:
$ ip route show | grep 169.254.169.254
169.254.169.254 dev eth0
In different cloud platforms, you will see different output.
In the context of GCP (Google Cloud Platform), instances can query
169.254.169.254 to access instance metadata, project metadata, and other information about the instance or running processes. The metadata server is a read-only server that provides instance-specific data.
You can access the metadata server from your instance using curl or any HTTP method. Here is an example of a curl command:
$ curl "http://metadata.google.internal/computeMetadata/v1/instance/?" -H "Metadata-Flavor: Google"
In the context of AWS, the IP address
169.254.169.254 is used as the endpoint for the instance metadata service. The AWS EC2 metadata service provides a way for EC2 instances to retrieve instance-specific information and configuration details.
When an EC2 instance makes a request to
169.254.169.254, it can access a range of metadata about the instance itself. This metadata includes information such as the instance ID, instance type, security group IDs, public and private IP addresses, IAM role, availability zone, and much more.
$ curl http://169.254.169.254/latest/meta-data/