Monitoring Google Compute Engine

How GCE monitoring works

Host-based monitoring: The GCE VM sensor does not use the external service account credentials file (cred.json) configured through credentials_path. GCE VM monitoring is host-based, which means the Instana agent must be installed directly on each GCE VM that you want to monitor. The agent monitors the VM where it is installed. Some other GCP services also support remote monitoring through cred.json.

Authentication method: The agent authenticates through the GCE metadata server (169.254.169.254), which provides instance metadata and an access token for the default service account that is attached to the VM. This service account could be different from the service account that you configure for monitoring other GCP services by using cred.json, unless you attached the same service account to the VM during its creation. A GCE VM can have only one service account attached at a time.

Label collection: To retrieve GCE instance labels and tags, the service account that is attached to the VM must have the compute.instances.get IAM permission at the project level. Without this permission, the agent can still collect basic instance metadata, but labels and tags cannot be collected.