This series walks you through: Building a Kubernetes cluster on cloud providers. Q6. Perhaps the StatefulSets run some distributed ledger network and each StatefulSet has a different role (e. We can use the kubectl describe secret command to display additional information about the resource. You should not run a database (or other stateful workload) as Deployment, use StatefulSet for those. This tool is tailored to provide developers with an experience of iteration…The containers in a pod talk to each other via local host, whereas pod-to-pod communication is done via services. The pod template specifies the container image and port to be used for the application. Amazon DocumentDB (with MongoDB compatibility) is a scalable, highly durable, and fully managed database service for operating mission-critical MongoDB-compatible JSON based workloads. In Kubernetes, a Deployment is a workload resource object that lets you configure the lifecycle of pods in the cluster. 4. kubectl describe svc nginx-app1. Deployment controllers are suitable for managing stateless applications. As with any. 3343 Perimeter Hill Drive. StatefulSet. One of the more powerful features of a StatefulSet is the use of persistent. 9. They provide stable pod identity, persistent per pod storage and ordered graceful deployment, scaling and rolling updates. If you need Pods to have their own persistent volume, then use StatefulSets. In this video I explained about StatefulSet in Kubernetes, the differences between Deployment Vs StatefulSet in Kubernetes, Why do you need statefulset in Kubernetes, so you will understand Statefulset in Kubernetes completely. kind: Service metadata: name: redis labels: app: redis spec: type: ClusterIP ports: - name: redis port: 6379 targetPort. service "nginx" created. It’s easy to use and has a wide range of features, making it an ideal choice for managing applications in a production environment. StatefulSets are intended to be used with stateful applications and distributed systems. Deployments vs Daemonsets vs Statefulsets. StatefulSets:Initially deployment should come up with 1 replicas when 1st node is created and grow as we add more worker/master nodes to it and once max is achieved, it should stop growing. Statefulsets are used for databases where the state of the application is the crucial part of the deployment. 而因為有關聯，所以在Deployment下的Label Name，會同樣印在pod上。. Overview. one replica pod will go down and the updated pod will come up. When pods run as part of a StatefulSet, Kubernetes keeps state data in the persistent storage volumes of the StatefulSet, even if the. In addition to managing the deployment and scaling of a set of Pods, StatefulSets provide guarantees about the ordering and uniqueness of those Pods. This blog post will discuss how this feature can be used. A StatefulSet is better suited to stateful workloads that require persistent storage on each cluster node, such as databases and other identity-sensitive workloads. If you need to use deployment instead of statefulset, just add kind: Deployment to the nodeSpecs. yaml kubectl apply -f mongo-statefulset. What then is the advantage of using StatefulSets?而因為有關聯，所以在Deployment下的Label Name，會同樣印在pod上。. Given this difference, Deployment is more suited to work with stateless applications. In this example, a custom Cassandra seed provider lets the database discover new Cassandra instances as they join the Cassandra cluster. First of all Headless services are vaguely used to access all the pod replicas directly instead of using the Services. For stateless applications, using Deployment objects is most suitable. Deploy it using the command below: $ kubectl apply -n test-namespace -f deployment. StatefulSets. Parallel pod management tells the StatefulSet controller to launch or terminate all Pods in parallel, and not to wait for Pods to become Running and Ready or completely terminated prior to launching or terminating another Pod. A template describes a set of objects that can be parameterized and processed to…This task shows how to scale a StatefulSet. headless service is necessary to create a stable DNS name for each pod. Example. StatefulSets are a Kubernetes resource specifically designed to manage stateful applications. Ordered, graceful deployment and scaling. Just like StatefulSets, Kubernetes Deployments let you define the state of the application, and the Deployment’s controller is responsible for maintaining this state. To check your version of Kubernetes, run kubectl version. The example in this blog deploys on Centos7 using kubeadm. Deployment. The below example demonstrates the components of a StatefulSet. Kubernetes is an open-source orchestration system for automating deployment, scaling, and management of containerized applications. It can manage the scaling and deployment of a collection of. Pods (and, by extension, containers) are, nevertheless, short-lived entities. Otherwise, using StatefulSets will help ensure a number of requirements can be met for your stateful app. StatefulSets ensure that instances are deployed and scaled in a controlled and predictable order. Similarly, the deployment script. I want to deploy a single Pod on a Node to host my service (like GitLab for the example). On the other hand, Jenkins is a stateful application. This is useful in cases where the deployment process is stalled or requires adjustments. Statefulsets. StatefulSet is the workload API object used to manage stateful applications. For an even more than basic primer on StatefulSets, visit the Kubernetes documentation here. These are applications that can easily scale. Note: This is not a production configuration. If the deployment changes the Deployment controller creates a new ReplicaSet to replace the old one and takes care of a rolling. Specifying minReadySeconds slows down a rollout of a StatefulSet, when using a. Deployment vs. Stable Network Identities: StatefulSets provide stable network identities for each pod, making it easy to communicate with specific pods in the set. StatefulSets are created in a similar way to Deployment objects. 3 Creating a StatefulSet; 8. When using Kubernetes, most of the time you don’t care how your pods are scheduled, but sometimes you care that pods are. The “selector“ defines which Pods belong to the services. Let’s summarize the key differences between Deployments, StatefulSets, and DaemonSets: Deployments: Designed for stateless applications. For hostnames, stable network identifiers please refer to the statefulset basics: For a StatefulSet with N replicas, each Pod in the StatefulSet will be assigned an integer ordinal, from 0 up through N-1, that is unique over the Set A StatefulSet can use a Headless Service to control the domain of its Pods. . Kubernetes Statefulsets are used to deploy Stateful Applications. MySQL, PostgreSQL, Redis, Elasticsearch) onto Kubernetes. id-0, id-1, id-2 and so on) for each of their Pods. StatefulSet. The simplest method to expose your services is to use a NodePort , in which case your service will take on the IP of the node externally with a high port number (30000+). 26 introduced a new, alpha-level feature for StatefulSets that controls the ordinal numbering of Pod replicas. but there is a hick. 8 Deploying Stateful Microservices: StatefulSets. StatefulSets maintain the state of applications beyond an individual pod lifecycle. StatefulSets Example Step 1 - Create Kube Environment. StatefulSets. Each new pod in statefulset then have a new PV attached to. As far as a Deployment is concerned, Pods are interchangeable. Define a Stateful Set with PVC. StatefulSets: Use StatefulSets to deploy stateful applications. StatefulSets manage the creation, scaling, and deletion of pods. 💡Check out Kubernetes Deployments: The Ultimate Guide to understand more about how Deployments and ReplicaSets are used in a production setting. Published on Sep. First Note : The pod-template-hash label is added by the Deployment controller to every ReplicaSet that a Deployment creates or adopts. com. This is great for stateless apps that we want online, ASAP. Create Some Data. Key takeaways: What is controller concept in Kuberenetes. apps "web" created. g. Free Forever plan: 10,000 series metrics;. 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. also during upgrades and deployments. This will be a standalone tutorial. 那使用Deployments更重要的是，可以方便Rollback到之前版本，而使用StatefulSets、DaemonSets. Examples include databases like MySQL, PostgreSQL, and Redis, HTTP servers like NGINX and Apache, and persistent brokers like Kafka and Zookeeper. You can also learn how to Deploy a stateful application. Note: While ReplicaSets can be used, Kubernetes recommends using Deployments. First, let's verify that StatefulSet has created the leader ( mehdb-0) and. The list of stateful charts using a. yaml. A pod in a StatefulSet can fail, but the persistent pod identifier will enable. : Using StatefulSets. A number of features intrinsic with the use of StatefulSets are the guarantees around deployment and scaling. Ordered Deployment and Scaling. If you set CPU requests = 1 for every workload there will be no more capacity soon to schedule new pods. Stable unique network identifiers. Using it, each of your pods is guaranteed the same network identity and disk across restarts, even if it's rescheduled to a different physical machine. Deployment manages creating Pods by means of ReplicaSets. There seems to be a recurring bad practice among the charts in this repository: using a Deployment to manage pods using Persistent Volume Claims, rather than the proper StatefulSet. In the above YAML file, we have defined a simple StatefulSet to deploy a PostgreSQL database. Let's be friends: Explore managing stateful applications with Kubernetes StatefulSets —. and data from the image is copied to only one PVC where are rest two pods. Sorted by: 21. DaemonSets StatefulSets are Kubernetes resources that allow us to deploy and manage the stateful application. It manages the deployment and scaling of a set of Pods, and provides guarantee about. This deployment mode is the easiest way to deploy Loki at scale. Use the right-hand menu to navigate. The domain managed by this Service. You can also create Pods (containers) using the Deployment object in the Kubernetes cluster. Represents the latest available observations of a statefulset’s current state. You might set the Deployment to have replicas: 3 so that if one of them fails the other two can pick up the load. Not all together. All three of these are defined via YAML configuration, are created as an object in the cluster, and are then managed on an ongoing basis by a Kubernetes controller. StatefulSet vs. The list of stateful charts. Currently there are several API groups in use:A StatefulSets provides a persistent identity to the pods that they create and manage. Stable, persistent storage. StatefulSet vs. This isn't possible using a Deployment. It allows us to automate deployments, scale, and manage containerized applications. DaemonSets are designed to run background services that are required by the other containers in the cluster, such as logging and monitoring agents, while StatefulSets are used to run stateful applications. Pods in StatefulSets have reliable network identities. Modelling Stability with StatefulSets. 1. updateStrategy. But it's important to carefully evaluate whether your database is a good fit for Kubernetes and how best to make it work in a Kubernetes environment. Let's be friends: Explore managing stateful applications with Kubernetes StatefulSets — when to use them, how to deploy MongoDB. Pods (and, by extension, containers) are, nevertheless, short-lived entities. 6. What are StatefulSets and why are they needed? Deployments vs StatefulSets TL;DR. With the clean service created, proceed to deploy it as shown below. Like a Deployment, a StatefulSet manages Pods. There is confusion amongst Kubernetes users as to when one should make a Deployment with a PVC and when they should use a StatefulSet with a PVC. Coordinators, brokers, and routers are stateless in nature, thus deployments make more sense and avoid complexities to manage statefulsets. It allows you to define the Kubernetes Deployment or StatefulSet that you want KEDA to scale based on a scale trigger. Some of the key features of StatefulSets are as follows: 1. . Eg. This allows Pods to maintain individual state that's separate from their neighbors in the set. Open this file in a code-editor and write the following code into it: apiVersion: apps/v1. To understand about Statefulset you need to know how generally database deployments. A StatefulSet’s YAML manifest defines a template for its Pods. However, these StatefulSets configurations involve some complexity—so you must carefully plan your deployments before them carrying out. Ordered, graceful deployment and scaling. 9, so your version doesn't has support for it. In Kubernetes, StatefulSets are trying to solve the problem of your data going away when a Kubernetes Pod is destroyed. They give Pods a stable identity and consistent ordering during scaling operations. Un StatefulSet es el objeto de la API workload que se usa para gestionar aplicaciones con estado. With Deployment, a failed pod will be migrated to other worker. You may notice two things here: (1) there is only one pod created while we asked for three, and (2) the pod name contains the StatefulSet name. 3343 Perimeter Hill Drive. It works fine, but since resources like databases are stateful I thought of using Statefulset for the mongodb, but now the problem is, when I go through the documentation, statefulset has volumeClaimTemplates instead of volumes (in. As their name suggests,. I have a kubernetes cluster and I have a simple deployment for mongodb with NFS persistent volume set. CPU requests are mostly more important for the kube-scheduler to identify the best node suitable to place a pod. Ordered, automated rolling updates. HPA is a Kubernetes component that automatically updates workload resources such as Deployments and StatefulSets, scaling them to match demand for applications in the cluster. It makes sense also as each Redis instance relies on a configuration file that keeps track of other cluster instances and their roles. Download and install a kubectl greater than v1. Kubernetes deployments manage stateless services running on your cluster (as opposed to for example StatefulSets which manage stateful services). What is the difference between them. Stateful and Stateless Applications. Before you begin StatefulSets are only available in Kubernetes version 1. Our current updateStrategy is. In summary, StatefulSets are great building blocks for running stateful workloads on Kubernetes. Statefulsets is used for Stateful applications, each replica of the pod will have its own state, and will be using its own Volume. Statefulsets is used for Stateful applications, each replica of the pod will have its own state, and will be using its own Volume. Note: While ReplicaSets can be used, Kubernetes recommends using Deployments. Deployments vs Statefulsets. Download and install a kubectl greater than v1. Within each pod, is there any way (through environment variable injection or similar) for us to get a unique identifier that. So in total we wait 55 Minutes just to fill up the capacity. Hint: It starts at FREE. While a StatefulSet keeps a unique identity for each Pod it manages. Share. As a result, sometimes other Kubernetes services compete with the stateful service over available resources. Represents the latest available observations of a statefulset’s current state. StatefulSets provide the ability to use persistent volumes for each. Pods created as part of a StatefulSet are given persistent identifiers that they retain even when they’re rescheduled. It strikes a balance between deploying in monolithic mode or deploying each component. StatefulSets. A StatefulSet is a workload API object for managing stateful applications. Deployments allow you to define the lifecycle of applications, including the container images they use, the number of pods and the manner of updating them. Al igual que un Deployment, un StatefulSet gestiona Pods que se basan en una especificación idéntica de contenedor. authorization. In the previous blog we created a stateless application, deployed with K8s resource Deployment, which allows one to replicate the application, but where data is lost when Pods are restarted, meaning there were no data consistency. For example, look at web_stateful. After successfully starting kube-apiserver and kube-controller-manager, you will see AvailableReplicas in the status and. The volumeClaimTemplates automatically creates a new PersistentVolumeClaim each time a pod is replicated. Deployment is used to deploy stateless applications. 0 version. StatefulSets. In this tutorial, we will discuss two different ways to deploy our containerized application on Kubernetes using Deployment and StatefulSets resources. full vs. Today, we’ll take a look at some of the same YAML markup, but zero in on StatefulSets instead. “Hay otro, el ReplicationController pero Kubernetes ahora apunta a Deployment que automáticamente crea ReplicaSets”. Remember that the default. The same thing can be done by using StatefulSets. To summarize, we changed db Deployment into a StatefulSet, we added a command that creates MongoDB. Kubernetes Deployment vs. Overview. In this article we examined how StatefulSets work, and how they differ from a Deployment. A Kubernetes pod is a cluster deployment unit that typically contains one or more containers. Each pod has a persistent identifier, that it maintains across any. Roll back a deployment. Understanding ReplicaSet vs. Other examples of stateful applications include MySQL clusters, Redis, Kafka, MongoDB, and others. The StatefulSet controller uses this field as a collision avoidance mechanism when it needs to create the name for the newest ControllerRevision. 3343 Perimeter Hill Drive. Workload Resources StatefulSets StatefulSets StatefulSet is the workload API object used to manage stateful applications. 🚀 KubeSphere v3. Why use StatefulSets. In my understanding JGroups Cluster is designed to work with stable node identities like they are provided by statefulset. . StatefulSet:. Gestiona el despliegue y escalado de un conjunto de Pods, y garantiza el orden y unicidad de dichos Pods. Kubernetes StatefulSets provide two main advantages (for stateful applications) over Deployments: a stable identity of the pods and the ability to follow specific Deployment orders. Due to this issue¹ automatic rollback in case of failed upgrade is not possible. StatefulSet Kubernetes | Understand what StatefulSet in Kubernetes is and how it works Using StatefulSet in practice 🙅🏼♀️ youtu. Contrairement à un Deployment, un. Deployments are usually used for stateless applications while StatefulSets are used for stateful applications. As a workload API object, a StatefulSet is used to manage stateful applications. A ReplicaSet (RS) is a Kubernetes object used to maintain a stable set of replicated pods running within a cluster at any given time. 5, we’ve moved the feature formerly known as PetSet into beta as StatefulSet. A Kubernetes pod is a cluster deployment unit that typically contains one or more containers. This page shows how to run a replicated stateful application using a StatefulSet. We'll use Jenkins as the first application we'll deploy. Get Started. StatefulSets are created in a similar way to Deployment objects. com. Unlike deployments, statefulset maintains an identity for each of the pods. Using a statefulset also ensures that pods. A DaemonSet ensures that a copy of a particular Pod is running on each node in a cluster or a subset of nodes, and it automatically adds or removes Pods from nodes as. statefulset "mariadb" deleted. But it's important to carefully evaluate whether your database is a good fit for Kubernetes and how best to make it work in a Kubernetes environment. kubectl create namespace database. Stable, persistent storage. But still for the alertmanager statefulset, only 1 pod is getting restarted. Kubernetes provides a variety of controllers that you can use to define how pods are set up and deployed within the Kubernetes cluster. You can use StatefulSets to deploy stateful applications and clustered applications that save data to persistent storage, such as Compute Engine persistent disks. You can also learn how to Deploy a stateful application. Step 2. Here you can see how the Deployment itself runs a ReplicaSet that then runs 3 pods. In a production environment it is better to use a declarative operation, e. Find a wide-ranging variety of Deployment Vs Statefulset In Kubernetes Statefulset In Kubernetes Explained Stateless Stateful classified ads on our high-quality marketplace. Identity and Stable Network hostnames: StatefulSets are used for those applications that require stable network identity and hostnames. In statefulsets each replica pod created has an index number starting from 0 and it will only setup the next replica if the previous one is running. It makes sense also as each Redis instance relies on a configuration file that keeps track of other cluster instances and their roles. Let’s understand both. com. Switch on the feature gate with the command line flag --feature-gates=StatefulSetMinReadySeconds=true on kube-apiserver and kube-controller-manager. kubernetes. These rules allow you to configure that a set of workloads should be co-located in the same defined topology; for example, preferring to place two related Pods onto the same node. With StatefulSets, you can deploy and manage your stateful applications on Kubernetes with confidence, knowing that they’re being managed in a way that’s familiar and intuitive. @billimek it feels like a similar conversation happened on the original helm repo, so I'm not able to find it there. This application is a replicated MySQL database. yml secret/mysecret created. This comes at a cost of slow scale ups and. KEDA will monitor that service and based on the events that occur it will automatically scale your resource out/in accordingly. g. Deployment. Deployments are a great choice for applications that don’t require any state to be maintained. Helm is a deployment orchestrator and includes pre and post hooks that can be used during an install or upgrade. 申请转载. At this point we have a running MySQL server, let's use this guide to simulate failover of a node. 22. It is rather unlikely that you will ever need to create Pods directly for a production use-case. A Deployment provides the following functions: It allows you to define the. persistent deployment manifest: As you can see its straight forward. 0. Here is a step by step tutorial on how to use StatefulSets and some basic operations on StatefulSets. yaml We need to create a pvc. StatefulSet is the workload API object used to manage stateful applications. A Kubernetes pod is a cluster deployment unit that typically contains one or more containers. If you want to delete just the StatefulSet and not the pods, use --cascade=false. Using StatefulSets to run Stateful applications at scale. be/JGtJj_nAA2s Kubernetes Operator explained (manager for your stateful application 🚀) youtu. They each have their own sticky identity, which they keep between. FYI: You had the right approach in the beginning with Deployment + PVC. A StatefulSet can deploy applications that need to reliably identify specific replicas, rollout updates in a pre-defined order, or. podManagementPolicy: "Parallel". It provides guarantees about the ordering and uniqueness of these Pods. StatefulSets Example. 2 StatefulSet vs Deployment; 8. Deployment vs. Open this file in a code-editor and write the following code into it: apiVersion: apps/v1. This allows you to easily replicate Pods and attach a storage volume to the Pods. If you are using Deployment, StatefulSet, DaemonSet, ReplicaSet or ReplicationController, to trigger a new deployment you will need to make a manual change to the pod template component of the configuration defined by the resource. Pods hold the containers for an application. StatefulSet use at-most-X semantics and Deployments use at-least-X semantics, where X is number of replicas. It maintains order when starting and stopping the pods. Deployment Spec vs StatefulSet Spec Deployment specs and StatefulSet specs are quite similar. Elaborate more on this if we should never use Deployment. StatefulSets. This sub-command will stop the current rollout and start a new one, using the current configuration settings. Suppose you see the pods using the kubectl get pods command. Both are related to the limited control that deployments provide over how an application runs: Lack of granular control. StatefulSets are Kubernetes resources that allow us to deploy and manage the stateful application. Both Deployment and StatefulSet try to maximize the availability - but StatefulSet cannot sacrifice data consistency (e. Stable, persistent storage. 4. イメージ的にはPodTemplateを持つDeploymentにPVCも追加した感じ。. Learn basic concepts of StatefulSets and how to create StatefulSets on KubeSphere. 3. This is essential. StatefulSets are a pain in the neck when you need to do rolling updates or to upgrade your Kubernetes version, because they are not too easy to scale. Why not to use the Statefulsets for stateless applications in Kubernetes ? As Stateful sets have the same capabilities as Deployment PVC, HPA, and others. 1 Like. For example, you define how many replicas ( pods) of your app you want to run in the deployment. Today, we’ll take a look at some of the same YAML markup, but zero in on StatefulSets instead. In order to understand how StatefulSet works, you first need to understand how database clusters work, as well concepts of Kubernets StatefulSet vs Deployment. Inter-pod affinity and anti-affinity can be even more useful when they are used with higher level collections such as ReplicaSets, StatefulSets, Deployments, etc. Deployments and StatefulSets are the most common way to scale workloads with KEDA. Uses ReplicaSets for scaling and updates. Pods (and, by extension, containers) are, nevertheless, short-lived entities. ReplicaSet vs. Kubernetes StatefulSet simply explained | Deployment vs StatefulSet. StatefulSets vs Deployments for stateless applications on Kubernetes. A number of features intrinsic with the use of StatefulSets are the guarantees around deployment and scaling. There are many benefits. Restarting a Rollout. 3. There is also a general lack of understanding when it comes to disk access policies, what RWO/RWX means, and what they allow you to do. A Deployment, on the other hand, is suitable for stateless workloads that use multiple replicas of one pod, such as web servers like Nginx and Apache. The primary idea behind StatefulSets is to allow developers to deploy applications that require data to be stored in a filesystem with the ability to re-attach to them if they restart by failure. For a typical Kubernetes Pod, it will be managed by a higher-level controller like a Deployment. When comparing a Deployment vs Replica Set, the former provides the same replication functions (through Replica Sets) and also the ability to rollout changes and roll them back if necessary. StatefulSets - A StatefulSet is similar to a deployment in that one or more identical pods are created and managed. Through StatefulSets, each Pod receives a stable, unique identifier, maintaining predictable and orderly deployment, which is indispensable for the. Stateful means having some volume. The database and Kubernetes itself run on the same machines. You are responsible for creating this Service. StatefulSets are valuable for applications that require one or more of the following. deployments should be should be used. This is true for both deployments and statefulsets (and pods, rcs, rss jobs, etc. Compare Kubernetes StatefulSet vs. StatefulSets 1. October 4, 2021 Topics: Cloud Volumes ONTAP, Elementary, Kubernetes What Is Kubernetes Deployment? A Deployment is a Kubernetes resource object used for declarative application updates. Pods created as part of a StatefulSet are given persistent identifiers that they retain even when they're rescheduled. Discover smart, unique perspectives on Statefulsets and the topics that matter most to you like Kubernetes, Deployment, DevOps, K8s, Mongodb, Persistent. Deployments and StatefulSets are the most common way to scale workloads with KEDA. updateStrategy is left unspecified. By default, Kubernetes deployment rollout history remains in the system so that you can roll back at any time. Create a stateful set. . is to have a global option setting for CF4K8s at installation time where is possible to specify if statefulsets vs. Figure-3 captures the state of the Kubernetes cluster. 1 Answer. See StatefulSet vs. But some apps need a stable environment, where objects are created in a known order with fixed names. Unlike in a standard Deployment, StatefulSets are aware that your application is stateful and will therefore treat it accordingly. g. js application to five replicas. A big advantage of Kubernetes and StatefulSets is that you can scale the number of MongoDB Replicas up and down with a single command! To scale up the number of replica set members from 3 to 5, run this command: kubectl scale --replicas=5 statefulset mongo. StatefulSets DaemonSets There is one other type ReplicationController but Kubernetes now favors Deployments as Deployments configure ReplicaSets to support. Very useful for HA workloads. Watch the presentation below given by Ali Kahoot, DevOps Engineer & Trainer at Tarabut Gateway. So yes, StatefulSet helps preserve the order and name of the pod, but what is it that it does extra (or different) that is advantageous over a regular Deployment with respect to volumes. spec. 7 StatefulSet vs Deployment: associated serviceIt watches changes in ConfigMap and Secrets and then updates Deployment, StatefulSet and DaemonSet, so that the new changes are loaded. KEDA will monitor that service and based on the events that occur it will automatically scale your resource out/in accordingly. 0 API compatibility in Amazon DocumentDB.