The example topology has a single primary server and multiple replicas, using asynchronous row-based replication. Let’s start by looking at the difference between a stateful and stateless application. By evaluating pod. 1. The rules are of the form “this pod should (or, in the case. It's because this particular Ingress controller enabled by an addon, binds to your host ( MicroK8S node) to ports 80, 443. DaemonSet. Utilisez un DaemonSet au lieu d’un ReplicaSet pour les pods qui fournissent une fonction au niveau du noeud, comme. If I call a kubectl describe on the ReplicaSet, just the first three pod creation events are showed, all successful. 1. DaemonSet controller will create Pods on nodes that match the node selector’s key and value. This is. ReplicaSets . A DaemonSet container has to service all targeted containers in a cluster node, whereas a Sidecar container can only service focus on containers in. annotations block. The command can create any resource like ReplicaSet, Deployment, Namespace, and more. Does not matter in which worker node they are running. Deployments #kubernetes #controllers #replicaset #statefulset #daemonset #deployments… Beliebt bei Asel Şeşen The blue book, by Eric Evans, is a must. As per Kubernetes docs :-. Possible Solution 2: set minAvailable to quorum-size (e. m The deployed Pods usually contain background processes that need to be disseminated throughout the entire cluster. Kubernetes Deployment vs. To get the yaml file try kubectl get deploy deploymentname -o yaml To update the pod with the new yaml file first either find and edit the yaml file or copy the contents and make the changes you want to make, then run: kubectl apply -f newDeployment. io docs - daemonset Although they had ReplicaSet, DaemonSet is the K8 object they added. Gestiona el despliegue y escalado de un conjunto de Pods, y garantiza el orden y unicidad de dichos Pods. As nodes are incorporated into the cluster, Pods are implemented to them. Migrate to the apps/v1 API, available since v1. Deployment 是 kubernetes 中最常用的资源对象，为 ReplicaSet 和 Pod 的创建提供了一种声明. As in the case of Deployment, a controller is created, but unlike Deployment, it does not create a ReplicaSet , but instead it itself creates replicas from pods and assigns them names. Use a Job instead of a ReplicaSet for Pods that are expected to terminate on their own (that is, batch jobs). Deployment. As nodes are added to the cluster, Pods are added to them. Dec 2, 2022. ReplicaSet ReplicaSet 的目的是维护指定数量的 Pod，常用做保障指定数量 Pod 的可用性 Deployment Deployment 是一个用来管理 ReplicaSet 的更高级概念，某种程度上我们不应该操作 ReplicaSet，而是直接使用 Deployment。Deployment 拥有 Rollout & Rollback 功能，方便我们管理。 StatefulSet StatefulSet 用来管理有状态的应用，其会. The total number of pods are managed by maxSurge and maxUnavailable. As nodes are added to the cluster, pods are added to them. A DaemonSet ensures that a copy of the Ingress Controller is running on every node in the cluster. DaemonSets ensures that all (or some) Nodes run a copy of a Pod. DaemonSet. We have used ReplicaSet and Deployment in the previous sessions but we will dive deeper here and you will understand their differences and when to use them. A Deployment provides declarative updates for Pods and ReplicaSets. ReplicaSets allow you to run multiple instances of your pod while ensuring that unhealthy pods are replaced. 4 of Kubernetes In Action by Marko Luksa, he says the kube-proxy is a DaemonSet but doesn't explicitly state that kubelets are. Both Application Load Balancer and Network Load Balancer are designed from the ground…The Azure Monitor metrics agent's architecture utilizes a ReplicaSet and a DaemonSet. 1 /5. A ReplicaSet is probably one of the first concepts that you’ll learn, cause it’s such an important part of what you can achieve with Kubernetes, but shouldn’t be confused with a DaemonSet; also a critical feature. Deployment options. StatefulSet is the workload API object used to manage stateful applications. Kubectl Command Cheatsheet. Deleting the other pods, the ReplicaSet and the Deployment, does not make any difference. DaemonSet vs. It is generally recommended to deploy the Nginx Ingress Controller as a DaemonSet. It will show three Pods. This included ReplicationController, ReplicaSet, StatefulSet, DaemonSet, and Deployment. StatefulSet vs. $ kubectl apply -f deployment. Trivy Github Security Scan. You would have those many replicas running. Then take note of the Controlled By field. To see the actual status and to stay updated on the status of how the restart is going on. A side note!Understanding ReplicaSet vs. The ReplicaSet data includes the number of desired replicas, the selector to identify which pods are being controlled, and the template for the pod. This page contains a list of commonly used kubectl commands and flags. Kubernetes: Network Policies. Inside the pods are system or user applications packaged in containers. Deployments #kubernetes #replicaset #statefulset #daemonset #deployments #comparsion Deployment uses spec. Deployments. Use daemonsets to create shared storage, run a logging pod on every node in your cluster, or deploy a monitoring agent on every node. Deployments #kubernetes #replicaset #statefulset #daemonset #deployments #comparsion DaemonSet controller // uses this field as a collision avoidance mechanism when it needs to // create the name for the newest ControllerRevision. com 3Add a comment. At most one pod of the. Each rollback updates the revision of the Deployment. As opposed to the legacy check, with the Kubernetes State Metrics Core check, you no longer need to deploy kube-state-metrics in your cluster. Guy is a developer & trainer with more than 25 years of experience. Unlike other replication controllers, DaemonSets cannot be scheduled for failure. # deployment name and namespace deployment_name=mydeployment deployment_ns=mynamespace # get replica set identifier for deployment dep_rs=$. kubectl create secret <secret type> <secret-name> --from-literal=<key>=<value>. What is ReplicasSets? A ReplicaSet is a process that runs multiple instances of a Pod and keeps the specified number of Pods constant. Use a Job instead of a ReplicaSet for Pods that are expected to terminate on their own (that is, batch jobs). StatefulSet vs. If you specify --cascade=orphan with kubectl, then the Pods will be left on the nodes. As you said, DaemonSet guarantees one pod per node for a subset of the nodes in the cluster. Pods by themselves don't do much, even if they're hosted on nodes. If it succeeds, the command returns: daemonset "<daemonset-name>" rolled back. ReplicaSet is available in Kubernetes Client using client. A daemonset can be used to run replicas of a pod on specific or all nodes in an OpenShift Container Platform cluster. g. kubectl basics. Learn how DaemonSets work, how to perform common operations like creating and scheduling a DaemonSet, and the difference between StatefulSets and DaemonSets. This means that if any pod dies, it is immediately noticeable. In Kubernetes, a HorizontalPodAutoscaler automatically updates a workload resource (such as a Deployment or StatefulSet), with the aim of automatically scaling the workload to match demand. What you want to do is drain the node before restarting it. StatefulSet vs. For a particular service. In order to do so, I've added the following configuration to the container spec on the application. A ReplicaSet delegates local container restarts to some agent on the node such as Kubelet. Warning: In a cluster where not all users are trusted, a malicious user could. A DaemonSet creates a replica on each worker node by default. From a configuration perspective, DaemonSet is similar to a ReplicaSet or a Deployment. Understanding ReplicaSet vs. Whenever a node is added to the cluster, the DaemonSet controller checks if it is. Follow. When you begin learning about Kubernetes, you hear about the different types of sets it supports and start wondering about their differences. A regular ReplicaSet or Deployment would not be appropriate because you couldn't reliably identify the Pod running the primary replica. Create a deployment. A DaemonSet ensures that all (or some) Nodes run a copy of a Pod. In applications of robotics and automation, a control loop is a non-terminating loop that regulates the state of the system. When you updated the Deployment, it created a new ReplicaSet (nginx-deployment-1564180365) and scaled it up to 1 and then scaled down the old ReplicaSet. Like a Deployment, a StatefulSet manages Pods that are based on an identical container spec. DaemonSet defines Pods that provide facilities that are local to nodes. The controller is in charge of providing as many Pods as desired/stated in the spec by creating or deleting them by monitoring the cluster’s Pod resources. ReplicaSet; DaemonSet; StatefulSet; Images. spec. Each new ReplicaSet updates the revision of the Deployment. We can also use kubectl set image to update container image in a yaml file without applying it: kubectl set image -f definition. of pods in the Kubernetes cluster on any node. Understanding ReplicaSet vs. yaml - defines an Nginx app where logs are written to a HostPath volume, directly using the node's diskkubectl restart. First, you need to add a label to the node. Manages the deployment and scaling of a set of Pods, and provides. A ReplicaSet’s purpose is to maintain a stable set of replica Pods running at any given time. You would have those many replicas running at any point of time in the kubernetes cluster. Package daemonset provides Registry interface and its RESTStorage implementation for storing DaemonSet api objects. Every change is a new version. 3. DaemonSetは更新の際にはDeployment同様にローリングアップデートが可能だ。 DaemonSetのフィールドについて. Plus I think it’s more common to use “kubectl run” when imperatively creating a Pod. Job, ReplicaSet,Deployment & DaemonSet supports Set-based selectors. Utilisez un DaemonSet au lieu d’un ReplicaSet pour les pods qui fournissent une fonction au niveau du noeud, comme le monitoring ou la gestion des logs de ce noeud. Let’s talk about our final set type: a DaemonSet. Their IP addresses are drawn from an internal. How do they differ while persisting data. What Is DaemonSet vs Replica? DaemonSet is going to make sure that each and every node is going to have atleast one replica and replica is the copys of the applications. apiVersion: apps/v1 kind: DaemonSet metadata: # Unique key of the DaemonSet instance name: daemonset-example spec: selector: matchLabels: app: daemonset-example template: metadata: labels: app: daemonset-example spec: containers: # This container is run once on each Node in the cluster - name: daemonset-example image: ubuntu:trusty. A DaemonSet is a controller that ensures that the pod runs on all the nodes of the cluster. The ReplicaSet pod scrapes cluster-wide targets such as kube-state-metrics and custom application targets that are specified. Deployments #kubernetes #replicaset #daemonset #orchestration #dockercontainer #traininganddevelopment #cloudnative A typical resource request provides exclusive access to GPUs. Saving this config into hpa-rs. kubectl apply -f postgresql. Rollback to an earlier Deployment revision if the current state of the Deployment is not stable. #linux #linuxsystemadministration #fedora #opensource #redhatlinux This file shows the contents of pid’s memory mapped the same way as in the process, i. Kubernetes API is growing day by day and they are adding new features every day. 23. Technically the update strategy defined in the deployment manifest is applied every time the PodSpec changes, no matter whether it changes through helm or kubectl or something else. Nowadays, we use. ReplicaSets are generally considered a “bridge” to deployments – the use of which is generally considered a best practice when using Kubernetes. Follow. Gunakan DaemonSet alih-alih ReplicaSet untuk Pod yang menyediakan fungsi pada level mesin, seperti monitoring mesin atau logging mesin. Copy. Rollback to an earlier Deployment revision if the current state of the Deployment is not stable. As nodes are removed from the cluster, those pods are garbage collected. field that defines the number of Pods to run. 11. DaemonSets are most often used to run background software, such as a monitoring agent, on each node in a cluster. 1. a kernel panic. The DaemonSet can be looked down upon by a lot of people for its subjectively resource-intensive approach to Pod replication but used. 6 Kubernetes Deployment Strategies: Roll. In-depth attack surface risk knowledge enables you to apply the right security controls to manage your cyber risk. When a DaemonSet is deleted, Kubernetes removes all the pods. Stateful vs Stateless. DaemonSet. This is important for a few reasons: It ensures that the Ingress Controller is always available to serve traffic, even if a node fails. # kubectl delete rs soaktestrs replicaset "soaktestrs" deleted # kubectl get pods Again, the pods that were created are deleted when we delete the Replica Set. Usa un DaemonSet en vez de un ReplicaSet para aquellos Pods que proporcionan funcionalidad a nivel de servidor, como monitorización de servidor o logging de servidor. Each new ReplicaSet updates the revision of the Deployment. You can see Trivy scanned our helm chart and uploaded the scan to Github Security Tab. ReplicaSets are a higher-level API that gives the ability to easily run multiple instances of a given pod. Labels can be used to organize and to select subsets of objects. Currently, it is being maintained by the cloud native computing foundation (CNCF). 5. As nodes are removed. On the other hand, deployment is detailed as "Package deployment contains all the logic for handling Kubernetes Deployments". DoK #49 Deployments vs. replicas: 2 a new ReplicaSet is created, and it observes the. DaemonSet. That is also what kubectl rollout restart. Un StatefulSet es el objeto de la API workload que se usa para gestionar aplicaciones con estado. The latest feature they added was DaemonSet. You can also configure it to scrape any custom targets at the node level with static configs. To improve fault tolerance, instead, they should always be part of a Deployment, DaemonSet, ReplicaSet or StatefulSet. The Pod(s) maintained by a ReplicaSet has metadata. A DaemonSet ensures a copy of a Pod is running across a set of nodes in a Kubernetes cluster. Also, the DaemonSet controller will use the original template the next time a node (even with the same name) is created. Each new ReplicaSet updates the revision of the Deployment. Ingress. The table below shows the primary differences between a StatefulSet and a Deployment: Aspect Deployment. use the node affinity/anti-affinity and/or node selector to control the set of nodes to run on (similar to how DaemonSet does it). 10 min read. As nodes are added to the cluster, Pods are added to them. chuyenphatnhanhdhlvn. Create a deployment. Estos Pods tienen un. A DaemonSet ensures that all (or some) Nodes run a copy of a Pod. Production-Grade Container Scheduling and Management. A DaemonSet allows you to overcome Kubernetes’ scheduling limitations and makes sure that a specific app gets deployed on all the nodes within the cluster. For example, a log collector daemon gathering log data from all the other programs. StatefulSet: how to choose. For deploying the sample counter app using a DaemonSet, we will be using the following manifest. Replica Set is the next generation of Replication Controller. Share. kubectl Dry Run Option. Implement distributed tracing with Jaeger & Opentelemetry on Kubernetes #kubernetes #distributedtracing #opentelemetry #jaeger #microservices…Saket Jain. kc delete namespace my-namespace. DaemonSets guarantee a single instance of a pod runs on each eligible node. scale it down to zero and then to the number of pods you required (guess it equals to 3) kubectl scale deployment <deployment-name> --replicas=0 -n <namespace> kubectl scale deployment <deployment-name> --replicas=3 -n <namespace>. You have to use node selector to control replicas. DaemonSet vs. RollingUpdate: This is the default update strategy. Tolerations allow scheduling but don't. 1. Command used to. @jevgenij-alterman @posquit0 the reason is simple: you don't need a high number of NGINX instances to handle high volumes of traffic and most importantly, you need to keep in mind that each instance of the ingress controller needs to reach the kubernetes API server. Replication controller is kinda imperative, but replica sets try to be as declarative as possible. When a ReplicaSet needs to create new Pod(s), it uses its Pod template. Create a deployment. This wouldn’t be possible if a Deployment or ReplicaSet was used, as scheduling or replication changes would. A ReplicaSet, as the name implies, is a set of replicas (Pods) maintained with their Revision history. C. Deployments #kubernetes #replicaset #statefulset #daemonset #deployments #comparsion can list all of the nodes in your cluster with. Example: environment not in( dev,test) ,kubectl get pods -l 'environment notin (dev)' Key, Operator and Value with matchExpressions are used in Set-based selectors . There is no way to force x pods per node the way a Daemonset does. The ReplicaSet creates 1000 Pods and maintains a Status field with the number of healthy Pods. Usa un DaemonSet en vez de un ReplicaSet para aquellos Pods que proporcionan funcionalidad a nivel de servidor, como monitorización de servidor o logging de servidor. Further, both pods and ReplicaSets are used by deployments. 5 or before. If a user-facing Pod fails or becomes overworked, the Deployment allocates work to a Pod from the ReplicaSet to maintain responsiveness. DaemonSet. Conforme se elimina nodos del clúster, dichos Pods se destruyen. Now get the Pods list using the following command. DaemonSets are used to deploy system daemons such as log collectors and monitoring agents, which typically must run on every node. A DaemonSet is a Kubernetes resource that ensures a specified Pod runs on all nodes or a specific subset of nodes in a cluster. Package deployment contains all the logic for handling Kubernetes Deployments. The ReplicaSet is responsible to manage the Pods. It allows us to automate deployments, scale, and manage containerized. In a deployment or replicaSet you can use podAffinity and podAntiaffinity. For kinds in the extensions/v1beta1, apps/v1beta1, and apps/v1beta2 group versions, unless you specify otherwise, dependent objects are orphaned by default. As you can see the ADDRESS contains 127. Note the client provided takes precedence over the configured transport values. Rollback to an earlier Deployment revision if the current state of the Deployment is not stable. Report this post INSPIRAS 1,078,188 followers 1yDaemonSet. They ensure that a pod is replicated on some or all of the nodes. DaemonSet vs. We run the following command in k8s. This helps to ensure that the DaemonSet is present on each node without triggering node recreation. Besides being able to update it on a deployment we can also do it for pod, replicationcontroller , daemonset and replicaset. Kubernetes Replication Controller Vs DeploymentThis is the same behavior of DaemonSet in Kubernetes version 1. Current Behavior. ReplicaSet helps bring up a new instance of. Then, list all the deployments in your cluster with the command: kubectl get deployments. If you subsequently create a new DaemonSet with the same selector, the new DaemonSet adopts the existing Pods. StatefulSet is the workload API object used to manage stateful applications. A DaemonSet ensures a copy of a Pod is running across a set of nodes in a Kubernetes cluster. Verification: To verify the Datadog Agent is running in your environment as a DaemonSet, execute: kubectl get daemonset. Un ReplicationController garantiza que un número determinado de réplicas se estén ejecutando en todo momento. A DaemonSet in Kubernetes is like a chef in a restaurant. namespaces. Deployments and Deployment Configurations. With deployment you should be able to do rolling upgrade or rollback. To manually delete a ReplicaSet, run the following command: kubectl delete rs <ReplicaSet_NAME> --cascade=false Next steps. kubectl get replicaset. But it actually takes a while before it can replace all the running pods with a new one. Pod と ReplicaSet の関係は疎結合になっている。. – Pixel Elephant. For example, If you create a deployment with 1 replica, it will check that the desired state of ReplicaSet is 1 and current state is 0, so it will create a ReplicaSet,. In this example: A Deployment named nginx-deployment is created, indicated by the . DaemonSets guarantee a single instance of a pod runs on each eligible node. The TTL-after-finished controller assumes that a Job is eligible to be cleaned up TTL seconds after the Job has finished. The pod-template-hash value has automatically been added to both the Labels and Selector of the ReplicaSet. You can not control its replica using scale option. Our integration collects Kubernetes data by instrumenting the container orchestration layer. Assignment – 1 1. kubernetes_state. A Daemonset is not going to run a couple of reproduction per node. A new replicaset is created and the deployment moves the pods from old replicaset to the new one, at the controlled rate. If you need to run a program / software in every node of the Kubernetes cluster, then this article might be of interest to you. Submit and view feedback for. DaemonSet. Unlike a. But what is the best for this case ? This Pod is stateful (I am using volume hostPath to keep the data) and is deployed using nodeSelector to keep it always on the same Node. The ReplicaSet can then establish the Pods it controls, so it knows whether the minimum availability target has been met. A new ReplicaSet is created and the Deployment manages moving the Pods from the old ReplicaSet to the new one at a controlled rate. ReplicaSet $ kubectl scale --replicas=3 rs/demo-replicaset. Kuberneters – Difference Between Replicaset and Replication Controller. A pipe is a form of redirection (transfer of standard output to some other destination) that is used in Linux to send the output of one command to another for further processing. daemons_available (gauge) The number of nodes that should be running the daemon pod and have one or more of the daemon pod running and available. yaml and submitting it to a Kubernetes cluster should create the defined HPA that autoscales the target ReplicaSet depending on the CPU usage of the replicated pods. Tolerations allow the scheduler to schedule pods with matching taints. For a simpler and more visual experience, use the. DaemonSets are a key component of the Kubernetes cluster and allow administrators to configure services (pods) across all or a subset of Kubernetes nodes with ease. Deployment is recommended for application services. As nodes are removed from the cluster, those. As nodes are removed from the. Lets say our current deployment has. Maxsurge tells us how many pods we can go up then the required number of pods. If a Node is added, the DaemonSet will automatically add a Pod to that Node. Looks up a deployment, replica set, stateful set, or replication controller by name and creates an autoscaler that uses the given resource as a reference. Kubernetes Replication Controller vs Deployment Deployments are intended to replace Replication Controllers. Bạn đang muốn tìm hiểu thông tin về chủ đề “How to connect to local instance of a Kubernetes DaemonSet from another DaemonSet”. 2. You describe a desired state in a Deployment, and the Deployment Controller changes the actual state to the desired state at a controlled rate. A ReplicaSet delegates local container restarts to some agent on the node such as Kubelet. This should trigger the creation of a new replicaset and automatically handle the restart based on the strategy specified in the deployment spec. . Create a deployment. Another point, Pods can’t be updated with apply. kubectl get daemonset List one or more daemonsets; kubectl edit daemonset. Tolerations are applied to pods. A Kubernetes pod is a cluster deployment unit. V tutorialu popisujeme 3 různé způsoby (Deployment, StatefulSet a DaemonSet), jak provádíme deploy aplikací v K8s – včetně praktické ukázky. Deployments - Semaphore Like Comment Share Copy; LinkedIn; Facebook; Twitter; To view or add a comment. As in the case of Deployment, a controller is created, but unlike Deployment, it does not create a ReplicaSet , but instead it itself creates replicas from pods and assigns them names. DaemonSet. The difference between StatefulSets and Deployments reflects the divide between stateful and stateless systems. It is the right controller for the job of deploying one Pod per node. Priority indicates the importance of a Pod relative to other Pods. In Kubernetes, containers are assigned to pods, which are abstractions of the containers' required hosting resources. Por ejemplo, si creamos un StatefulSet con el nombre counter, se creará un pod con el nombre counter-0, y para múltiples réplicas de un StatefulSet, sus nombres se incrementarán. En otras palabras, un ReplicationController se asegura que un pod o un conjunto homogéneo de pods. template. Each Pod in a DaemonSet performs a role similar to a system daemon on a classic Unix / POSIX server. StatefulSet vs. Its purpose is to maintain the specified number of Pod instances running in a cluster at any given time to prevent users from losing access to their application when a Pod fails or is inaccessible. template. A DaemonSet is an efficient way to deploy containers on multiple servers inside a Kubernetes cluster. This is known as Quality of Service (QoS) class. What is Kubernetes Daemonset? DaemonSet is a Kubernetes feature that lets you run a Kubernetes pod on all cluster nodes that meet certain criteria. What you want to do is drain the node before restarting it. To create and set up the Kubernetes replica set, we have to follow the below steps: 1. Check. 9. kubectl get pods Scaling Application: We can scale the application after created in various ways. Overview Kubernetes (K8s) is an open-source container orchestration system. A Daemonset assures that some or all Nodes run a copy of a Pod. DaemonSetは更新の際にはDeployment同様にローリングアップデートが可能だ。 DaemonSetのフィールドについて. 1. Restartable Batch Job: Concern: Job needs to complete in case of voluntary disruption. Delete the ReplicaSet Let's clean up before we move on. StatefulSet vs. Use a DaemonSet instead of a ReplicationController for pods that provide a machine-level function, such as machine monitoring or machine logging. 式的定义方法，在 Deployment 对象中描述一个期望的状态，Deployment 控制器就会按照一定的控制 速率把实际状态改成期望状态，通过定义一个 Deployment 控制器会创建一个新的. This means if you have lots of replicas, you are putting. This is where PDB s provide the added advantage over the Replicaset. Some typical uses of a DaemonSet are: running a cluster storage daemon, such as glusterd. ReplicaSet được tạo khi Deployment được tạo hoặc được chỉnh sửa và thật sự là ReplicaSet được dùng như định nghĩa để tạo Pod. 1. The child field matchLabels of the selector field is used to identify the pod and a replica field is used to indicate how many pods should be maintained. Get information about secret. This ensures that every node in the cluster receives a copy of the pod, making DaemonSets particularly. DaemonSet vs. There is one other type ReplicationController but Kubernetes now favors Deployments as Deployments configure ReplicaSets to support replication. Use a Job instead of a ReplicaSet for Pods that are expected to terminate on their own (that is, batch jobs). Managing workload objects. A ReplicaSet delegates local container restarts to some agent on the node such as Kubelet. Although they had ReplicaSet, DaemonSet is the K8 object they added. 16. DaemonSet. Static analysis of kubernetes resources can help us to identify security threats and fix them before the deployment. Delete a DaemonSet. StatefulSet (stable-GA in k8s v1. In the simplest case, a deployment just creates a new replication controller and lets it start up pods. A new ReplicaSet is created and the Deployment manages moving the Pods from the old ReplicaSet to the new one at a controlled rate. newrelic. Logging agents. Close navigation. the node disappears from the cluster due to cluster network partition. For example, we can trigger the RollingUpdate by changing the container image. Le champ template contient les sous-champs suivants:. I like to call it as “run everywhere thing” when I introduce it to newbies.