What is Azure Kubernetes Service (AKS) Network Observability?

Kubernetes is a powerful tool for managing containerized applications. As containerized environments grow in complexity, it can be difficult to identify and troubleshoot networking issues in a Kubernetes cluster.

Network observability is an important part of maintaining a healthy and performant Kubernetes cluster. By collecting and analyzing data about network traffic, you can gain insights into how your cluster is operating and identify potential problems before they cause outages or performance degradation.

Overview of Network Observability add-on in AKS

Networking Observability add-on operates seamlessly on Non-Cilium and Cilium data-planes. It empowers customers with enterprise-grade capabilities for DevOps and SecOps. This solution offers a centralized way to monitor network issues in your cluster for cluster network administrators, cluster security administrators, and DevOps engineers.

When the Network Observability add-on is enabled, it allows for the collection and conversion of useful metrics into Prometheus format, which can then be visualized in Grafana. Azure has offerings for managed Prometheus and Grafana.

• Azure managed Prometheus and Grafana: A managed service provided by Azure, taking care of the infrastructure and maintenance of Prometheus and Grafana, allowing you to focus on configuring and visualizing your metrics.

• Multi CNI Support: Network Observability add-on supports both Azure CNI and Kubenet network plugins.

Metrics

Network Observability add-on currently only supports node level metrics in both Linux and Windows platforms. The below table outlines the different metrics generated by the Network Observability add-on.

Metric Name	Description	Labels	Linux	Windows
networkobservability_forward_count	Total forwarded packet count	Direction, NodeName, Cluster	Yes	Yes
networkobservability_forward_bytes	Total forwarded byte count	Direction, NodeName, Cluster	Yes	Yes
networkobservability_drop_count	Total dropped packet count	Reason, Direction, NodeName, Cluster	Yes	Yes
networkobservability_drop_bytes	Total dropped byte count	Reason, Direction, NodeName, Cluster	Yes	Yes
networkobservability_tcp_state	TCP active socket count by TCP state.	State, NodeName, Cluster	Yes	Yes
networkobservability_tcp_connection_remote	TCP active socket count by remote address.	Address, Port, NodeName, Cluster	Yes	No
networkobservability_tcp_connection_stats	TCP connection statistics. (ex: Delayed ACKs, TCPKeepAlive, TCPSackFailures)	Statistic, NodeName, Cluster	Yes	Yes
networkobservability_tcp_flag_counters	TCP packets count by flag.	Flag, NodeName, Cluster	Yes	Yes
networkobservability_ip_connection_stats	IP connection statistics.	Statistic, NodeName, Cluster	Yes	No
networkobservability_udp_connection_stats	UDP connection statistics.	Statistic, NodeName, Cluster	Yes	No
networkobservability_udp_active_sockets	UDP active socket count	NodeName, Cluster	Yes	No
networkobservability_interface_stats	Interface statistics.	InterfaceName, Statistic, NodeName, Cluster	Yes	Yes

Limitations

• Pod level metrics aren't supported.

Scale

Certain scale limitations apply when you use Azure managed Prometheus and Grafana. For more information, see Scrape Prometheus metrics at scale in Azure Monitor

Next steps

• For more information about Azure Kubernetes Service (AKS), see What is Azure Kubernetes Service (AKS)?.

• To create an AKS cluster with Network Observability and Azure managed Prometheus and Grafana, see Setup Network Observability for Azure Kubernetes Service (AKS) - Azure managed Prometheus and Grafana.