# Collect container metrics with Netdata Thanks to close integration with Linux cgroups and the virtual files it maintains under `/sys/fs/cgroup`, Netdata can monitor the health, status, and resource utilization of many different types of Linux containers. Netdata uses [cgroups.plugin](https://github.com/netdata/netdata/blob/master/collectors/cgroups.plugin/README.md) to poll `/sys/fs/cgroup` and convert the raw data into human-readable metrics and meaningful visualizations. Through cgroups, Netdata is compatible with **all Linux containers**, such as Docker, LXC, LXD, Libvirt, systemd-nspawn, and more. Read more about [Docker-specific monitoring](#collect-docker-metrics) below. Netdata also has robust **Kubernetes monitoring** support thanks to a [Helmchart](https://github.com/netdata/netdata/blob/master/packaging/installer/methods/kubernetes.md) to automate deployment, collectors for k8s agent services, and robust [service discovery](https://github.com/netdata/agent-service-discovery/#service-discovery) to monitor the services running inside of pods in your k8s cluster. Read more about [Kubernetes monitoring](#collect-kubernetes-metrics) below. A handful of additional collectors gather metrics from container-related services, such as [dockerd](https://github.com/netdata/go.d.plugin/blob/master/modules/docker/README.md) or [Docker Engine](https://github.com/netdata/go.d.plugin/blob/master/modules/docker_engine/README.md). You can find all container collectors in our supported collectors list under the [containers/VMs](https://github.com/netdata/netdata/blob/master/collectors/COLLECTORS.md#containers-and-vms) and [Kubernetes](https://github.com/netdata/netdata/blob/master/collectors/COLLECTORS.md#containers-and-vms) headings. ## Collect Docker metrics Netdata has robust Docker monitoring thanks to the aforementioned [cgroups.plugin](https://github.com/netdata/netdata/blob/master/collectors/cgroups.plugin/README.md). By polling cgroups every second, Netdata can produce meaningful visualizations about the CPU, memory, disk, and network utilization of all running containers on the host system with zero configuration. Netdata also collects metrics from applications running inside of Docker containers. For example, if you create a MySQL database container using `docker run --name some-mysql -e MYSQL_ROOT_PASSWORD=my-secret-pw -d mysql:tag`, it exposes metrics on port 3306. You can configure the [MySQL collector](https://github.com/netdata/go.d.plugin/blob/master/modules/mysql/README.md) to look at `127.0.0.0:3306` for MySQL metrics: ```yml jobs: - name: local dsn: root:my-secret-pw@tcp(127.0.0.1:3306)/ ``` Netdata then collects metrics from the container itself, but also dozens [MySQL-specific metrics](https://github.com/netdata/go.d.plugin/blob/master/modules/mysql/README.md#charts) as well. ### Collect metrics from applications running in Docker containers You could use this technique to monitor an entire infrastructure of Docker containers. The same [enable and configure](https://github.com/netdata/netdata/blob/master/docs/collect/enable-configure.md) procedures apply whether an application runs on the host system or inside a container. You may need to configure the target endpoint if it's not the application's default. Netdata can even [run in a Docker container](https://github.com/netdata/netdata/blob/master/packaging/docker/README.md) itself, and then collect metrics about the host system, its own container with cgroups, and any applications you want to monitor. See our [application metrics doc](https://github.com/netdata/netdata/blob/master/docs/collect/application-metrics.md) for details about Netdata's application metrics collection capabilities. ## Collect Kubernetes metrics We already have a few complementary tools and collectors for monitoring the many layers of a Kubernetes cluster, _entirely for free_. These methods work together to help you troubleshoot performance or availability issues across your k8s infrastructure. - A [Helm chart](https://github.com/netdata/helmchart), which bootstraps a Netdata Agent pod on every node in your cluster, plus an additional parent pod for storing metrics and managing alarm notifications. - A [service discovery plugin](https://github.com/netdata/agent-service-discovery), which discovers and creates configuration files for [compatible applications](https://github.com/netdata/helmchart#service-discovery-and-supported-services) and any endpoints covered by our [generic Prometheus collector](https://github.com/netdata/go.d.plugin/blob/master/modules/prometheus/README.md). With these configuration files, Netdata collects metrics from any compatible applications as they run _inside_ of a pod. Service discovery happens without manual intervention as pods are created, destroyed, or moved between nodes. - A [Kubelet collector](https://github.com/netdata/go.d.plugin/blob/master/modules/k8s_kubelet/README.md), which runs on each node in a k8s cluster to monitor the number of pods/containers, the volume of operations on each container, and more. - A [kube-proxy collector](https://github.com/netdata/go.d.plugin/blob/master/modules/k8s_kubeproxy/README.md), which also runs on each node and monitors latency and the volume of HTTP requests to the proxy. - A [cgroups collector](https://github.com/netdata/netdata/blob/master/collectors/cgroups.plugin/README.md), which collects CPU, memory, and bandwidth metrics for each container running on your k8s cluster. For a holistic view of Netdata's Kubernetes monitoring capabilities, see our guide: [_Monitor a Kubernetes (k8s) cluster with Netdata_](https://github.com/netdata/netdata/blob/master/docs/guides/monitor/kubernetes-k8s-netdata.md). ## What's next? Netdata is capable of collecting metrics from hundreds of applications, such as web servers, databases, messaging brokers, and more. See more in the [application metrics doc](https://github.com/netdata/netdata/blob/master/docs/collect/application-metrics.md). If you already have all the information you need about collecting metrics, move into Netdata's meaningful visualizations with [seeing an overview of your infrastructure](https://github.com/netdata/netdata/blob/master/docs/visualize/overview-infrastructure.md) using Netdata Cloud.