inspektor gadget

Inspektor Gadget is a set of tools and framework for data collection and system inspection on Kubernetes clusters and Linux hosts using eBPF

inspektor-gadget

2252

245

Inspektor Gadget is a set of tools and framework for data collection and system inspection on Kubernetes clusters and Linux hosts using eBPF. It manages the packaging, deployment and execution of Gadgets (eBPF programs encapsulated in OCI images) and provides mechanisms to customize and extend Gadget functionality.

Note: Major new functionality was released in v0.31.0. Please read the blog post for a detailed overview.

Features

Build and package eBPF programs into OCI images called Gadgets
Targets Kubernetes clusters and Linux hosts
Collect and export data to observability tools with a simple command and via declarative configuration
Security mechanisms to restrict and lock-down which Gadgets can be run
Automatic enrichment: map kernel data to high-level resources like Kubernetes and container runtimes
Supports WebAssembly modules to post-process data and customize IG operators; using any WASM-supported language
Supports many modes of operation; cli, client-server, API, embeddable via Golang library

Quick start

The following examples use the trace_open Gadget which triggers when a file is open on the system.

Kubernetes

Deployed to the Cluster

krew is the recommended way to install
kubectl gadget. You can follow the
krew’s quickstart
to install it and then install kubectl gadget by executing the following
commands.

kubectl krew install gadget
kubectl gadget deploy
kubectl gadget run trace_open:latest

Check Installing on Kubernetes to learn more about different options.

Kubectl Node Debug

We can use kubectl node debug to run ig on a Kubernetes node:

kubectl debug --profile=sysadmin node/minikube-docker -ti --image=ghcr.io/inspektor-gadget/ig:latest -- ig run trace_open:latest

For more information on how to use ig without installation on Kubernetes, please refer to the ig documentation.

Linux

Install Locally

Install the ig binary locally on Linux and run a Gadget:

IG_ARCH=amd64
IG_VERSION=$(curl -s https://api.github.com/repos/inspektor-gadget/inspektor-gadget/releases/latest | jq -r .tag_name)

curl -sL https://github.com/inspektor-gadget/inspektor-gadget/releases/download/${IG_VERSION}/ig-linux-${IG_ARCH}-${IG_VERSION}.tar.gz | sudo tar -C /usr/local/bin -xzf - ig

sudo ig run trace_open:latest

Check Installing on Linux to learn more.

Run in a Container

docker run -ti --rm --privileged -v /:/host --pid=host ghcr.io/inspektor-gadget/ig:latest run trace_open:latest

For more information on how to use ig without installation on Linux, please check Using ig in a container.

MacOS or Windows

It’s possible to control an ig running in Linux from different operating systems by using the gadgetctl binary.

Run the following on a Linux machine to make ig available to clients.

sudo ig daemon --host=tcp://0.0.0.0:1234

Download the gadgetctl tools for MacOS
(amd64,
arm64) or windows and run the Gadget specifying the IP address of the Linux machine:

gadgetctl run trace_open:latest --remote-address=tcp://$IP:1234

The above demonstrates the simplest command. To learn how to filter, export, etc. please consult the documentation for the run command.

Core concepts

What is a Gadget?

Gadgets are the central component in the Inspektor Gadget framework. A Gadget is an OCI image that includes one or more eBPF programs, metadata YAML file and, optionally, WASM modules for post processing.
As OCI images, they can be stored in a container registry (compliant with the OCI specifications), making them easy to distribute and share.
Gadgets are built using the ig image build command.

You can find a growing collection of Gadgets on Artifact HUB. This includes both in-tree Gadgets (hosted in this git repository in the /gadgets directory and third-party Gadgets).

See the Gadget documentation for more information.

⚠️ For versions prior to v0.31.0

Prior to v0.31.0, Inspektor Gadget only shipped gadgets embedded in its executable file. As of v0.31.0 these built-in Gadgets are still available and work as before, but their use is discouraged as they will be deprecated at some point. We encourage users to use image-based Gadgets going forward, as they provide more features and decouple the eBPF programs from the Inspektor Gadget release process.

What is enrichment?

The data that eBPF collects from the kernel includes no knowledge about Kubernetes, container
runtimes or any other high-level user-space concepts. In order to relate this data to these high-level
concepts and make the eBPF data immediately more understandable, Inspektor Gadget automatically
uses kernel primitives such as mount namespaces, pids or similar to infer which high-level
concepts they relate to; Kubernetes pods, container names, DNS names, etc. The process of augmenting
the eBPF data with these high-level concepts is called enrichment.

Enrichment flows the other way, too. Inspektor Gadget enables users to do high-performance
in-kernel filtering by only referencing high-level concepts such as Kubernetes pods, container
names, etc.; automatically translating these to the corresponding low-level kernel resources.

What is an operator?

In Inspektor Gadget, an operator is any part of the framework where an action is taken. Some operators are under-the-hood (i.e. fetching and loading Gadgets) while others are user-exposed (enrichment, filtering, export, etc.) and can be reordered and overridden.

Further learning

Use the project documentation to learn more about:

Kernel requirements

Kernel requirements are largely determined by the specific eBPF functionality a Gadget makes use of.
The eBPF functionality available to Gadgets depend on the version and configuration of the kernel running
running in the node/machine where the Gadget is being loaded. Gadgets developed by the Inspektor
Gadget project require at least Linux 5.10 with BTF enabled.

Refer to the documentation for a specific Gadget for any notes regarding requirements.

Code examples

There are some examples in this folder showing the usage
of the Golang packages provided by Inspektor Gadget. These examples are
designed for developers that want to use the Golang packages exposed by
Inspektor Gadget directly. End-users do not need this and can use
kubectl-gadget or ig directly.

Contributing

Contributions are welcome, see CONTRIBUTING.

Community Meeting

We hold community meetings regularly. Please check our calendar
for the full schedule of up-coming meetings and please add any topic you want to discuss to our meeting
notes
document.

Slack

Join the discussions on the #inspektor-gadget channel in the Kubernetes Slack.

Thanks

BPF Compiler Collection (BCC): some of the gadgets are based on BCC tools.
kubectl-trace: the Inspektor Gadget architecture was inspired from kubectl-trace.
cilium/ebpf: the gadget tracer manager and some other gadgets use the cilium/ebpf library.

License

The Inspektor Gadget user-space components are licensed under the
Apache License, Version 2.0. The BPF code templates are licensed
under the General Public License, Version 2.0, with the Linux-syscall-note.