Hubble

Free plan APILinuxSelf-hosted

What Hubble is

Hubble is a networking and security observability platform for cloud native workloads, built around Cilium and eBPF. It discovers Kubernetes service dependencies across L3/L4 and L7, then displays data flows in a service map that users can visualize and filter. Flow details include individual TCP connections, DNS queries, HTTP requests, Kafka communication, and other network and application protocol traffic.

Monitoring examples include network behavior, network policy activity, HTTP request and response rates and latency, and DNS request and response monitoring. Security views can reveal connections blocked by network policy, services reached from outside a cluster, and services resolving particular DNS names. Visibility can cover a node, a cluster, or multiple clusters; Hubble Relay enables cluster-wide or Cluster Mesh views.

The Hubble API normally runs on the node with the Cilium agent, and the CLI queries it through a local Unix Domain Socket. Hubble UI provides browser-based visualization and filtering. The project is self-hosted, supports Kubernetes, and is open source under the Apache License. Hubble is free. The CLI, Server, Metrics, and Relay are stable; the UI is beta and should be used cautiously in critical production workloads.

Who it suits

Hubble suits teams running Kubernetes workloads that need visibility into network flows, service dependencies, or network policy activity. It is also relevant to operators who want node, cluster, or multi-cluster views and can run a self-hosted project.

What it does well

Discovers Kubernetes dependencies across L3/L4 and L7.
Shows TCP, DNS, HTTP, Kafka, and other flows.
Provides node, cluster, and multi-cluster visibility.
Includes browser-based service map visualization and filtering.
Open source under the Apache License.

What to know first

Hubble UI is beta and cautioned for critical production workloads.
Only the latest Hubble CLI version is maintained.

Limits

Hubble is free. Hubble UI is beta and should be used cautiously in critical production workloads; only the latest Hubble CLI version is maintained.

Plans

Plan	Billed and limits	Price
Hubble	Open source · Apache License	Free

As github.com lists them, read 5 Oct 2026. The maker's own page has the final word.

Getting started

Open the Hubble project on GitHub.
Use Hubble as a self-hosted deployment with Kubernetes.
Run the Hubble CLI to query the API through the local Unix Domain Socket.
Use Hubble Relay for cluster-wide or Cluster Mesh visibility.
Open Hubble UI in a browser to visualize and filter dependencies and flows.
Configure TLS for the Hubble API or TLS client certificates for UI connections to a TLS-enabled Relay, as needed.

Verdict

Choose Hubble if you need open-source network and security observability for Kubernetes, including service maps and flow-level visibility. Teams relying on the web interface in critical production workloads should account for its beta status.

Questions

How much does Hubble cost?

Hubble is free and is open source under the Apache License.

Does Hubble have a free trial?

No. The listed free trial status is no; the project is free.

Which operating systems are supported?

The listed supported operating systems are Linux, macOS, and Windows. The platform listing also includes API, Linux, and self-hosted.

Does Hubble support Kubernetes?

Yes. Hubble discovers Kubernetes service dependencies and provides network visibility for cloud native workloads.

What integrations are named?

Hubble is built on Cilium and eBPF. Cilium documentation names Prometheus and Grafana among monitoring systems that integrate with its metrics and alerting.

Which parts of Hubble are stable?

The CLI, Server, Metrics, and Relay are listed as stable. Hubble UI is beta.

Facts from Hubble's own pages

API access: By default, the Hubble API operates on the node where the Cilium agent runs, and the Hubble CLI queries it through a local Unix Domain Socket. · docs.cilium.io, 5 Oct 2026
Compatibility: The Hubble CLI is backward compatible with supported Cilium releases, and only the latest Hubble CLI version is maintained. · github.com, 5 Oct 2026
Deployment scope: Hubble can provide visibility at node, cluster, or multi-cluster scope; Hubble Relay enables cluster-wide or Cluster Mesh visibility. · docs.cilium.io, 5 Oct 2026
Flow visibility: It provides visibility into individual TCP connections, DNS queries, HTTP requests, Kafka communication, and other network and application protocol flows. · github.com, 5 Oct 2026
Integrations: Hubble is built on Cilium and eBPF; Cilium documentation names Prometheus and Grafana among monitoring systems that integrate with its metrics and alerting. · docs.cilium.io, 5 Oct 2026
License: The project is open source and licensed under the Apache License. · github.com, 5 Oct 2026
Metrics: Its monitoring examples include network behavior, network policy observation, HTTP request and response rates and latency, and DNS request and response monitoring. · github.com, 5 Oct 2026
Purpose: Hubble is a distributed networking and security observability platform for cloud native workloads, built on Cilium and eBPF. · github.com, 5 Oct 2026
Security configuration: The documentation describes configuring TLS for the Hubble API and TLS client certificates when connecting Hubble UI to a TLS-enabled Relay. · docs.cilium.io, 5 Oct 2026
Security observability: Hubble can show connections blocked by network policy, services accessed from outside a cluster, and services resolving particular DNS names. · github.com, 5 Oct 2026
Service maps: It automatically discovers Kubernetes service dependencies at L3/L4 and L7 and visualizes and filters data flows as a service map. · github.com, 5 Oct 2026
Stability: The repository lists Hubble CLI, Server, Metrics, and Relay as stable, while Hubble UI is beta and should be used with caution in critical production workloads. · github.com, 5 Oct 2026
Support: The project directs users to the Cilium Slack #hubble channel to ask questions and share experiences with developers and users. · github.com, 5 Oct 2026
Web interface: Hubble UI is a web interface for visualizing and filtering service dependencies and data flows, accessed through a browser. · docs.cilium.io, 5 Oct 2026

Where Hubble stands on Freedom251

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