# Node feature discovery for [Kubernetes](https://kubernetes.io) [![Build Status](https://api.travis-ci.org/kubernetes-incubator/node-feature-discovery.svg?branch=master)](https://travis-ci.com/kubernetes-incubator/node-feature-discovery) [![Go Report Card](https://goreportcard.com/badge/github.com/kubernetes-incubator/node-feature-discovery)](https://goreportcard.com/report/github.com/kubernetes-incubator/node-feature-discovery) - [Overview](#overview) - [Command line interface](#command-line-interface) - [Feature discovery](#feature-discovery) - [Feature sources](#feature-sources) - [Feature labels](#feature-labels) - [Getting started](#getting-started) - [System requirements](#system-requirements) - [Usage](#usage) - [Building from source](#building-from-source) - [Targeting nodes with specific features](#targeting-nodes-with-specific-features) - [References](#references) - [License](#license) - [Demo](#demo) _**NOTE:** We are gathering evidence in order to graduate from the Kubernetes incubator. If you are a user of the project, please add yourself to [this list](https://github.com/kubernetes-incubator/node-feature-discovery/wiki/Users) with as much detail as you are comfortable providing (name and email optional)._ ## Overview This software enables node feature discovery for Kubernetes. It detects hardware features available on each node in a Kubernetes cluster, and advertises those features using node labels. This project uses GitHub [milestones](https://github.com/kubernetes-incubator/node-feature-discovery/milestones) for release planning. ## Command line interface To try out stand-alone, one can run a Docker container where node-feature-discovery is already set as entry point. Such run is useful for checking features-detection part, but labeling part is expected to fail. It is recommended to use --no-publish and --oneshot to achieve clean run in stand-alone case. ``` node-feature-discovery. Usage: node-feature-discovery [--no-publish] [--sources=] [--label-whitelist=] [--oneshot | --sleep-interval=] [--config=] [--options=] node-feature-discovery -h | --help node-feature-discovery --version Options: -h --help Show this screen. --version Output version and exit. --config= Config file to use. [Default: /etc/kubernetes/node-feature-discovery/node-feature-discovery.conf] --options= Specify config options from command line. Config options are specified in the same format as in the config file (i.e. json or yaml). These options will override settings read from the config file. [Default: ] --sources= Comma separated list of feature sources. [Default: cpuid,iommu,kernel,local,memory,network,pci,pstate,rdt,selinux,storage] --no-publish Do not publish discovered features to the cluster-local Kubernetes API server. --label-whitelist= Regular expression to filter label names to publish to the Kubernetes API server. [Default: ] --oneshot Label once and exit. --sleep-interval= Time to sleep between re-labeling. Non-positive value implies no re-labeling (i.e. infinite sleep). [Default: 60s] ``` **NOTE** Some feature sources need certain directories and/or files from the host mounted inside the NFD container. Thus, you need to provide Docker with the correct `--volume` options in order for them to work correctly when run stand-alone directly with `docker run`. See the [template spec](https://github.com/kubernetes-incubator/node-feature-discovery/blob/master/node-feature-discovery-daemonset.yaml.template) for up-to-date information about the required volume mounts. ## Feature discovery ### Feature sources The current set of feature sources are the following: - [CPUID][cpuid] for x86/Arm64 CPU details - IOMMU - Kernel - Local (user-specific features) - Memory - Network - Pstate ([Intel P-State driver][intel-pstate]) - RDT ([Intel Resource Director Technology][intel-rdt]) - Selinux - Storage ### Feature labels The published node labels encode a few pieces of information: - Namespace, i.e. `feature.node.kubernetes.io` - The source for each label (e.g. `cpuid`). - The name of the discovered feature as it appears in the underlying source, (e.g. `AESNI` from cpuid). - The value of the discovered feature. Feature label names adhere to the following pattern: ``` /-[.] ``` The last component (i.e. `attribute-name`) is optional, and only used if a feature logically has sub-hierarchy, e.g. `sriov.capable` and `sriov.configure` from the `network` source. _Note: only features that are available on a given node are labeled, so the only label value published for features is the string `"true"`._ ```json { "feature.node.kubernetes.io/cpuid-": "true", "feature.node.kubernetes.io/iommu-": "true", "feature.node.kubernetes.io/kernel-config.": "true", "feature.node.kubernetes.io/kernel-version.": "", "feature.node.kubernetes.io/memory-": "true", "feature.node.kubernetes.io/network-": "true", "feature.node.kubernetes.io/pci-.present": "true", "feature.node.kubernetes.io/pstate-": "true", "feature.node.kubernetes.io/rdt-": "true", "feature.node.kubernetes.io/selinux-": "true", "feature.node.kubernetes.io/storage-": "true", "feature.node.kubernetes.io/-": "" } ``` The `--sources` flag controls which sources to use for discovery. _Note: Consecutive runs of node-feature-discovery will update the labels on a given node. If features are not discovered on a consecutive run, the corresponding label will be removed. This includes any restrictions placed on the consecutive run, such as restricting discovered features with the --label-whitelist option._ ### X86 CPUID Features (Partial List) | Feature name | Description | | :------------: | :----------------------------------------------------------: | | ADX | Multi-Precision Add-Carry Instruction Extensions (ADX) | AESNI | Advanced Encryption Standard (AES) New Instructions (AES-NI) | AVX | Advanced Vector Extensions (AVX) | AVX2 | Advanced Vector Extensions 2 (AVX2) | BMI1 | Bit Manipulation Instruction Set 1 (BMI) | BMI2 | Bit Manipulation Instruction Set 2 (BMI2) | SSE4.1 | Streaming SIMD Extensions 4.1 (SSE4.1) | SSE4.2 | Streaming SIMD Extensions 4.2 (SSE4.2) | SGX | Software Guard Extensions (SGX) ### Arm64 CPUID Features (Partial List) | Feature name | Description | | :------------: | :----------------------------------------------------------: | | AES | Announcing the Advanced Encryption Standard | EVSTRM | Event Stream Frequency Features | FPHP | Half Precision(16bit) Floating Point Data Processing Instructions | ASIMDHP | Half Precision(16bit) Asimd Data Processing Instructions | ATOMICS | Atomic Instructions to the A64 | ASIMRDM | Support for Rounding Double Multiply Add/Subtract | PMULL | Optional Cryptographic and CRC32 Instructions | JSCVT | Perform Conversion to Match Javascript | DCPOP | Persistent Memory Support ### IOMMU Features | Feature name | Description | | :------------: | :---------------------------------------------------------------------------------: | | enabled | IOMMU is present and enabled in the kernel ### Kernel Features | Feature | Attribute | Description | | ------- | ------------------- | -------------------------------------------- | | config | <option name> | Kernel config option is enabled (set 'y' or 'm').
Default options are `NO_HZ`, `NO_HZ_IDLE`, `NO_HZ_FULL` and `PREEMPT` | version | full | Full kernel version as reported by `/proc/sys/kernel/osrelease` (e.g. '4.5.6-7-g123abcde') |
| major | First component of the kernel version (e.g. '4') |
| minor | Second component of the kernel version (e.g. '5') |
| revision | Third component of the kernel version (e.g. '6') Kernel config file to use, and, the set of config options to be detected are configurable. See [configuration options](#configuration-options) for more information. ### Local (User-specific Features) NFD has a special feature source named *local* which is designed for running user-specific feature detector hooks. It provides a mechanism for users to implement custom feature sources in a pluggable way, without modifying nfd source code or Docker images. The local feature source can be used to advertise new user-specific features, and, for overriding labels created by the other feature sources. The *local* feature source tries to execute files found under `/etc/kubernetes/node-feature-discovery/source.d/` directory. The hooks must be available inside the Docker image so Volumes and VolumeMounts must be used if standard NFD images are used. The hook files must be executable. When executed, the hooks are supposed to print all discovered features in `stdout`, one feature per line. Hooks can advertise both binary and non-binary labels, using either `` or `=` output format. Unlike the other feature sources, the name of the hook, instead of the name of the feature source (that would be `local` in this case), is used as a prefix in the label name, normally. However, if the `` printed by the hook starts with a slash (`/`) it is used as the label name as is, without any additional prefix. This makes it possible for the hooks to fully control the feature label names, e.g. for overriding labels created by other feature sources. The value of the label is either `true` (for binary labels) or `` (for non-binary labels). `stderr` output of the hooks is propagated to NFD log so it can be used for debugging and logging. **An example:**
User has a shell script `/etc/kubernetes/node-feature-discovery/source.d/my-source` which has the following `stdout` output: ``` MY_FEATURE_1 MY_FEATURE_2=myvalue /override_source-OVERRIDE_BOOL /override_source-OVERRIDE_VALUE=123 ``` which, in turn, will translate into the following node labels: ``` feature.node.kubernetes.io/my-source-MY_FEATURE_1=true feature.node.kubernetes.io/my-source-MY_FEATURE_2=myvalue feature.node.kubernetes.io/override_source-OVERRIDE_BOOL=true feature.node.kubernetes.io/override_source-OVERRIDE_VALUE=123 ``` **NOTE!** NFD will blindly run any executables placed/mounted in the hooks directory. It is the user's responsibility to review the hooks for e.g. possible security implications. ### Memory Features | Feature name | Description | | :------------: | :---------------------------------------------------------------------------------: | | numa | Multiple memory nodes i.e. NUMA architecture detected ### Network Features | Feature | Attribute | Description | | ------- | ---------- | ----------------------------------------------------- | | sriov | capable | [Single Root Input/Output Virtualization][sriov] (SR-IOV) enabled Network Interface Card(s) present |
| configured | SR-IOV virtual functions have been configured ### PCI Features | Feature | Attribute | Description | | -------------------- | --------- | ----------------------------------------- | | <device label> | present | PCI device is detected The `` part is composed of raw PCI IDs, separated by dashes. The set of fields used in `` is configurable, valid fields being `class`, `vendor`, `device`, `subsystem_vendor` and `subsystem_device`. Defaults fields are `class` and `vendor`. An example label using the default label fields: ``` feature.node.kubernetes.io/pci-1200_8086.present=true ``` Also the set of PCI device classes that the feature source detects is configurable. By default, device classes (0x)03, (0x)0b40 and (0x)12, i.e. GPUs, co-processors and accelerator cards are deteted. See [configuration options](#configuration-options) for more information on NFD config. ### RDT (Intel Resource Director Technology) Features | Feature name | Description | | :------------: | :---------------------------------------------------------------------------------: | | RDTMON | Intel RDT Monitoring Technology | RDTCMT | Intel Cache Monitoring (CMT) | RDTMBM | Intel Memory Bandwidth Monitoring (MBM) | RDTL3CA | Intel L3 Cache Allocation Technology | RDTL2CA | Intel L2 Cache Allocation Technology | RDTMBA | Intel Memory Bandwidth Allocation (MBA) Technology ### Selinux Features | Feature name | Description | | :--------------: | :---------------------------------------------------------------------------------: | | selinux | selinux is enabled on the node ### Storage Features | Feature name | Description | | :--------------: | :---------------------------------------------------------------------------------: | | nonrotationaldisk | Non-rotational disk, like SSD, is present in the node ## Getting started ### System requirements 1. Linux (x86_64/Arm64) 1. [kubectl] [kubectl-setup] (properly set up and configured to work with your Kubernetes cluster) 1. [Docker] [docker-down] (only required to build and push docker images) ### Usage Feature discovery is preferably run as a Kubernetes DaemonSet. There is an example spec that can be used as a template, or, as is when just trying out the service: ``` kubectl create -f rbac.yaml kubectl create -f node-feature-discovery-daemonset.yaml.template ``` When the job runs, it contacts the Kubernetes API server to add labels to the node to advertise hardware features. If you have RBAC authorization enabled (as is the default e.g. with clusters initialized with kubeadm) you need to configure the appropriate ClusterRoles, ClusterRoleBindings and a ServiceAccount in order for NFD to create node labels. The provided templates will configure these for you. When run as a daemonset, nodes are re-labeled at an interval specified using the `--sleep-interval` option. In the [template](https://github.com/kubernetes-incubator/node-feature-discovery/blob/master/node-feature-discovery-daemonset.yaml.template#L26) the default interval is set to 60s which is also the default when no `--sleep-interval` is specified. Feature discovery can alternatively be configured as a one-shot job. There is an example script in this repo that demonstrates how to deploy the job in the cluster. ``` ./label-nodes.sh ``` The label-nodes.sh script tries to launch as many jobs as there are Ready nodes. Note that this approach does not guarantee running once on every node. For example, if some node is tainted NoSchedule or fails to start a job for some other reason, then some other node will run extra job instance(s) to satisfy the request and the tainted/failed node does not get labeled. [![asciicast](https://asciinema.org/a/11wir751y89617oemwnsgli4a.svg)](https://asciinema.org/a/11wir751y89617oemwnsgli4a) ### Configuration options NFD supports a configuration file. The default location is `/etc/kubernetes/node-feature-discovery/node-feature-discovery.conf`, but, this can be changed by specifying the`--config` command line flag. The file is read inside the Docker image, and thus, Volumes and VolumeMounts are needed to make your configuration available for NFD. The preferred method is to use a ConfigMap. For example, create a config map using the example config as a template: ``` cp node-feature-discovery.conf.example node-feature-discovery.conf vim node-feature-discovery.conf # edit the configuration kubectl create configmap node-feature-discovery-config --from-file=node-feature-discovery.conf ``` Then, configure Volumes and VolumeMounts in the Pod spec (just the relevant snippets shown below): ``` ... containers: volumeMounts: - name: node-feature-discovery-config mountPath: "/etc/kubernetes/node-feature-discovery/" ... volumes: - name: node-feature-discovery-config configMap: name: node-feature-discovery-config ... ``` You could also use other types of volumes, of course. That is, hostPath if different config for different nodes would be required, for example. The (empty-by-default) [example config](https://github.com/kubernetes-incubator/node-feature-discovery/blob/master/node-feature-discovery.conf.example) is used as a config in the NFD Docker image. Thus, this can be used as a default configuration in custom-built images. Configuration options can also be specified via the `--options` command line flag, in which case no mounts need to be used. The same format as in the config file must be used, i.e. JSON (or YAML). For example: ``` --options='{"sources": { "pci": { "deviceClassWhitelist": ["12"] } } }' ``` Configuration options specified from the command line will override those read from the config file. Currently, the only available configuration options are related to the [PCI](#pci-features) and [Kernel](#kernel-features) feature sources. ## Building from source Download the source code. ``` git clone https://github.com/kubernetes-incubator/node-feature-discovery ``` **Build the container image:** ``` cd make ``` **NOTE: Our default docker image is hosted in quay.io. To override the `QUAY_REGISTRY_USER` use the `-e` option as follows: `QUAY_REGISTRY_USER= make image -e`** You can also specify a build tool different from Docker, for example: ``` make IMAGE_BUILD_CMD="buildah bud" ``` Push the container image (optional, this example with Docker) ``` docker push //: ``` **Change the job spec to use your custom image (optional):** To use your published image from the step above instead of the `quay.io/kubernetes_incubator/node-feature-discovery` image, edit `image` attribute in the file [node-feature-discovery-job.yaml.template](node-feature-discovery-job.yaml.template#L23) to the new location (`//[:]`). ## Targeting Nodes with Specific Features Nodes with specific features can be targeted using the `nodeSelector` field. The following example shows how to target nodes with Intel TurboBoost enabled. ```yaml apiVersion: v1 kind: Pod metadata: labels: env: test name: golang-test spec: containers: - image: golang name: go1 nodeSelector: feature.node.kubernetes.io/pstate-turbo: 'true' ``` For more details on targeting nodes, see [node selection][node-sel]. ## References Github issues - [#28310](https://github.com/kubernetes/kubernetes/issues/28310) - [#28311](https://github.com/kubernetes/kubernetes/issues/28311) - [#28312](https://github.com/kubernetes/kubernetes/issues/28312) [Design proposal](https://docs.google.com/document/d/1uulT2AjqXjc_pLtDu0Kw9WyvvXm-WAZZaSiUziKsr68/edit) ## Kubernetes Incubator This is a [Kubernetes Incubator project](https://github.com/kubernetes/community/blob/master/incubator.md). The project was established 2016-08-29. The incubator team for the project is: - Sponsor: Dawn Chen (@dchen1107) - Champion: David Oppenheimer (@davidopp) - SIG: sig-node ## License This is open source software released under the [Apache 2.0 License](LICENSE). ## Demo A demo on the benefits of using node feature discovery can be found in [demo](demo/). [cpuid]: http://man7.org/linux/man-pages/man4/cpuid.4.html [intel-rdt]: http://www.intel.com/content/www/us/en/architecture-and-technology/resource-director-technology.html [intel-pstate]: https://www.kernel.org/doc/Documentation/cpu-freq/intel-pstate.txt [sriov]: http://www.intel.com/content/www/us/en/pci-express/pci-sig-sr-iov-primer-sr-iov-technology-paper.html [docker-down]: https://docs.docker.com/engine/installation [golang-down]: https://golang.org/dl [gcc-down]: https://gcc.gnu.org [kubectl-setup]: https://coreos.com/kubernetes/docs/latest/configure-kubectl.html [node-sel]: http://kubernetes.io/docs/user-guide/node-selection