You are configuring Cloud Logging for a new application that runs on a Compute Engine instance with a public IP address. A user-managed service account is attached to the instance. You confirmed…

Exporting service account keys is a security anti-pattern and not recommended for authentication within GCP, as instance service accounts are designed to provide credentials automatically.

While the default Compute Engine service account often has broad permissions, it's a general practice to use custom service accounts with the principle of least privilege, so this is not the recommended first step.

For an application or agent running on a Compute Engine instance to write logs to Cloud Logging, the service account associated with that instance must have the `roles/logging.logWriter` IAM role. This role grants the permissions required to create log entries in Cloud Logging, ensuring that logs emitted by the agents can be successfully ingested and displayed.

Private Google Access is for instances without external IP addresses to reach Google APIs over internal IP addresses; since the instance has a public IP, this setting is irrelevant to the logging issue.