Cilium is an open-source software for providing, securing, and observing network connectivity between container workloads. It is particularly known for its use of eBPF (extended Berkeley Packet Filter) technology to provide high-performance networking, security, and observability. Hubble is a component of Cilium that offers observability into the network and security behavior of applications running on Kubernetes. It provides metrics, logs, and traces to help diagnose network issues and understand application behavior.
One common issue users may encounter is the unavailability of Hubble metrics. This symptom is typically observed when attempting to access Hubble metrics through the Hubble UI or CLI, and no data is displayed. This can hinder the ability to monitor and troubleshoot network traffic effectively.
The root cause of Hubble metrics not being available often stems from misconfiguration or network connectivity issues. Hubble relies on a correctly configured environment to collect and display metrics. If there are issues with the configuration or network, Hubble may not function as expected.
Misconfigurations can occur in various parts of the Hubble setup, such as incorrect service accounts, missing permissions, or improper configuration of the Hubble Relay or UI components.
Network issues can prevent Hubble from collecting data from the Cilium agents. This can be due to firewall rules, network policies, or other connectivity barriers within the Kubernetes cluster.
To resolve the issue of Hubble metrics not being available, follow these steps:
Ensure that Hubble is correctly configured. Check the Hubble configuration files and verify that all necessary components are enabled and properly set up. You can refer to the official Hubble documentation for detailed configuration guidelines.
Ensure that there are no network policies or firewall rules blocking communication between Hubble components and Cilium agents. You can use tools like kubectl to inspect network policies:
kubectl get networkpolicies -A
Review the output to ensure that necessary traffic is allowed.
Ensure that the service accounts used by Hubble have the necessary permissions. You can check the roles and bindings using:
kubectl get roles,rolebindings -n kube-system
Make sure that the Hubble components have the required access to the Kubernetes API.
If configuration and network settings are correct, try restarting the Hubble components to refresh their state. Use the following command to restart the Hubble pods:
kubectl rollout restart deployment/hubble-relay -n kube-system
Repeat this for other Hubble components as necessary.
By following these steps, you should be able to diagnose and resolve the issue of Hubble metrics not being available. Proper configuration and network connectivity are crucial for Hubble to function correctly. For further assistance, consider reaching out to the Cilium community or consulting the Cilium documentation.
(Perfect for DevOps & SREs)
(Perfect for DevOps & SREs)
