Create firewall rules on GCP for Flask and observability components

Configure GCP firewall for OpenTelemetry

To allow inbound traffic for the Flask application and observability components, you must create a firewall rule in the Google Cloud Console.

Required ports

Create a firewall rule in GCP

To expose the TCP ports listed above, create a firewall rule.

Navigate to the Google Cloud Console , go to VPC Network > Firewall, and select Create firewall rule.

Create a firewall rule

Next, create the firewall rule that exposes the TCP ports. Set the Name of the new rule to allow-all-opentelemetry. Select the network you intend to bind to your VM (the default is default, but your organization may use a different one).

Set Direction of traffic to “Ingress”. Set Allow on match to “Allow” and Targets to “Specified target tags”.

Creating opentelemetry firewall rule

Next, enter allow-all-opentelemetry in the Target tags field. Set Source IPv4 ranges to 0.0.0.0/0.

Creating the Opentelemetry firewall rule

Finally, select Specified protocols and ports under the Protocols and ports section. Select the TCP checkbox, enter 8080,16686,9090,4317,4318,8889 in the Ports field, and select Create.

Specifying TCP ports for OpenTelemetry

What you’ve accomplished and what’s next

You’ve successfully:

• Created firewall rules in Google Cloud to expose ports for the Flask application and observability components
• Configured network access for Jaeger, Prometheus, and OpenTelemetry Collector endpoints
• Set up secure ingress rules for telemetry data collection

Next, you’ll provision a Google Axion C4A Arm virtual machine and apply these firewall rules to enable external access to your observability stack.