Platform Overview. February 4, 2021. Now run the kubectl apply command to create the secret in Kubernetes. This ensures the highest data quality and completeness, and also allows the Collector to leverage the Prometheus ecosystem of exporters to scrape targets. Initially it was designed as Facebook as an infrastructure for their messaging platform. First, we should create some data on our MySQL server: 5. It creates. In this example: A Deployment named nginx-deployment is created, indicated by the . 1. However, unlike a Deployment, a StatefulSet maintains a sticky identity (i. Unlike a Deployment, a StatefulSet maintains a. In this article, we will deploy a clustered Prometheus setup that integrates Thanos. statefulsets do ordinal scheduling; first pod 0, then pod 1, etc. See Writing a Deployment Spec for more details. Kubernetes controllers are the powerful means by which the platform regulates itself to ensure it maintains the desired conditions. Kubernetes persistent volumes (PVs) are a unit of storage provided by an administrator as part of a Kubernetes cluster. elasticsearch 검색을 위한 statefulset 생성을 시작하기 전에 statefulset 에는 필요할 때마다 볼륨을 생성할 수 있는 사전 정의된. default. You can also learn how to Deploy a stateful application. yaml. While Kubernetes StatefulSet offers a host of options to manage stateful applications. I am trying to convert one Deployment to StatefulSet in Kubernetes. io/hostname operator: In values: - docker-desktop SC kind: StorageClass apiVersion: storage. Un controlador de Deployment proporciona actualizaciones declarativas para los Pods y los ReplicaSets. Deployment creates ReplicaSet with the number of replicas=3. These. kubectl get service. kubectl rollout restart deploy -n namespace1 will restart all deployments in specified namespace with zero downtime. 14. 26 introduced a new, alpha-level feature for StatefulSets that controls the ordinal numbering of Pod replicas. The Operator extends the Kubernetes API with the RabbitmqCluster object. Regular ReplicaSets and Deployments aren’t suitable for this situation. Unlike a Deployment, a StatefulSet. We can use the kubectl describe secret command to display additional information about the resource. You can use a Deployment resource with a node selector to schedule pods on specific nodes. Pods deployed by Deployment are identical and interchangeable, created in random order with random hashes in their Pod. If you have a specific, answerable question about how to use Kubernetes, ask it on Stack Overflow. Some of the most common functions include creating and scaling database instances and facilitating database backups. 22 introduced a new ReadWriteOncePod access mode for PersistentVolumes and PersistentVolumeClaims. We can expose our application to the internet with the following command: $ kubectl expose deployment ghost-blog --type="LoadBalancer" --name=ghost-blog-service --port=80 --target-port=2368. Unlike stateless applications, stateful applications require stable and persistent storage, as well as. Clients can connect using that virtual IP address, and Kubernetes then load-balances traffic to that Service across the. They differ in terms of. Following the same logic, if something happens to any of the pods, it will be recreated with the same name. This name will become the basis for the ReplicaSets and Pods which are created later. Deployment with Node Selector. The deployment uses a selector to match labels defined in the pod template. In GKE, a default StorageClass allows you to dynamically provision Compute Engine persistent disks. For example, if you create a StatefulSet named “my-statefulset” with three replicas, the pod names would be “my-statefulset-0”, “my-statefulset-1”, and “my-statefulset-2”. Introduction Managing storage is a distinct problem from managing compute instances. StatefulSet vs. Instead, it returns the IP addresses of the pods associated with it directly to the DNS system, allowing clients to connect to individual pods directly. Once the yaml for statefulset is created, we need to apply the deployment using the following command: kubectl apply -f statefulset. A StatefulSet is a Kubernetes API object for managing stateful application workloads. Now, I have a task to introduce persistence for RabbitMq. cluster. Check. I am using the "Kubernetes Continuous Deploy Version1. StatefulSet is recommended because Atlantis stores its data on disk and so if. Unlike deployments, statefulset maintains an identity for each of the pods. MySQL settings remain on insecure defaults to. The Airflow Operator creates and manages the necessary Kubernetes resources for an Airflow deployment and supports the creation of Airflow schedulers with different Executors. This may seem a little odd, but it’s a very useful and. I'm using Logstash on Kubernetes and use the official Helm chart at this link. Aug 25, 2023 10 min read Statefulset Deployment Kubernetes As Kubernetes continues its ascent as a leading container orchestration platform, it's common for users to. Question 1: What is the difference between a StatefulSet and a Deployment in Kubernetes? When would you use one over the other? A Deployment in Kubernetes is used to manage a set of identical Pods. These can be used to make sure that a pod. Deployment vs. yamlI get many questions about Kubernetes and persistence. Each cluster contains one or more nodes. You can also create Pods. Repeat steps 1-3 two more times. They are not interchangeable. e. Get Full-Length High-Quality DevOps Tutorials for Free - Subscribe Now. In Kubernetes, one method of managing these actions is by using StatefulSets. Below is my Deployment description . Why use StatefulSets. Unlike a Deployment, a StatefulSet maintains a sticky identity for each of their Pods. In this example: A Deployment named nginx-deployment is created, indicated by the . But what is the best for this case ? E. Adding a volume to a Kubernetes StatefulSet using kubectl patch. It is an ordered. Get the pods using the following command and see the Pods have numbers as Suffix in the Pod name. Kubernetes Tutorial for Beginners. How to run stateful applications in Kubernetes. Let’s take a look at Deployments, DaemonSets, and StatefulSets. Difference in attaching volumes for storage in a Deployment and StatefulSet. A StatefulSet is a set of pods with a unique, persistent hostname and ID. StatefulSets. Rather, a deployment is a file that defines a pod's desired behavior or characteristics. But it differs from a Deployment in that it is more suited for stateful apps. Kubernetes Deployments are. Feedback. Kubernetes StatefulSet is the workload API object used to manage stateful applications. You can find controllers that run outside. To deploy MongoDB as a Replica Set with multiple pods, a Kubernetes StatefulSet deployment will be required. A diferencia. Deploying a. 2. This is referred to as at most. A StatefulSet is a workload API object for managing stateful applications. Using volumeClaimTemplates, each replica will get a unique PersistentVolumeClaim with statefulset whereas all replicas would share the PersistentVolumeClaim with a deployment. A HorizontalPodAutoscaler (HPA for short) automatically updates a workload resource (such as a Deployment or StatefulSet), with the aim of automatically scaling the workload to match demand. While a StatefulSet keeps a unique identity for each Pod it manages. Summary. The state information and other resilient data for any given StatefulSet pod are stored in the persistent disks of the StatefulSet. Deployments use ReplicaSets as a mechanism to orchestrate Pod creation, deletion, and updates. Can I do it with Deployment?I don't see any problem with this. As their name suggests,. yaml. Add 1 new node to the cluster, increase replicas in my StatefulSet to 4 and wait for the new Cockroachdb pod to fully sync. This binded volume is claiming ressources through the persistent volume claim. In most cases, users ignore how their pods are scheduled. StatefulSet is a Kubernetes controller that provides a way to run stateful applications in a cluster. Author: Matthew Cary (Google) Kubernetes v1. You can use Kubernetes annotations to attach arbitrary non-identifying metadata to objects. 5, we’ve moved the feature formerly known as PetSet into beta as StatefulSet. This application is a replicated MySQL database. After learning that we should have used a StatefulSet instead of a Deployment in order to be able to attach the same persistent volume to multiple pods and especially pods on different nodes, I tried changing our config accordingly. Storage classes can define properties of storage systems. To create a service, use the kubectl expose command. StatefulSetは状態を保持する (ステートフルな)アプリケーションを管理するためのKubernetesオブジェクトだ。. イメージ的にはPodTemplateを持つDeploymentにPVCも追加した感じ。. When using Kubernetes, most of the time you don’t care how your pods are scheduled, but sometimes you care that pods are deployed in order, that they have a persistent storage volume, or that they have a unique, stable network identifier across. I don't have specific material, I'd have to google it. Seperti halnya Deployment,. Deployment provides higher-level abstractions and additional features such as rolling updates, rollbacks, and versioning of the application. kubectl describe svc nginx-app1. Hi keycloak community, the keycloak operator currently creates the workloads as deployment which means that the pods are replaced by a new ones when they are restarted. This application is a replicated MySQL database. From what I can tell in the documentation, a ReplicaSet is created when running a Deployment. There seems to be general confusion as to when you should use a Deployment with a PVC and when you should use a StatefulSet with a PVC. As the name suggest the statefulsets are specifically used to make sure the app state is saved by each running pod. The volume (PVC) is shared across the pods. This means that a Deployment can scale up or down easily, as it is able to replace a pod if it fails. Operators follow Kubernetes principles, notably the control loop. StatefulSets are Kubernetes objects used to consistently deploy stateful application components. These priorities does not only happens when a Node becomes unreachable, but at all times, e. Deployment — เหมาะสำหรับงานที่แต่ละ Pod ทำงานเป็นอิสระจากกัน (Stateless) StatefulSet — เหมาะกับงานที่แต่ละ Pod มีลำดับ (1 2 3) หรือบทบาทต่างกันEditor’s note: this post is part of a series of in-depth articles on what's new in Kubernetes 1. Editor’s note: this post is part of a series of in-depth articles on what's new in Kubernetes 1. 9. When a deployment is created, Kubernetes builds pods to host application. One of the more powerful features of a StatefulSet is the use of persistent. I will have only one pod replica of RabbitMq. Run the below command to see external-IP of KeycloakA StatefulSet is a Kubernetes API object for managing stateful application workloads. yml 4. By interpreting the documentation, it seems that it depends on the event. It can be used to manage three Kubernetes objects: Deployment, DaemonSet, and. Deployment with name backend is created indicated by metadata. A single pod should never be run individually. Then, the second pod (2) does likewise. spec. svc. Stateless & Stateful come into the picture a lot while using Kubernetes. StatefulSets will represent the set of pods with different (unique), persistent identities, and elastic hostnames (stable). Kubernetes will automatically pick Docker as the default container runtime. It will create three Pods named web-0,web-1,web-2. Catatan: StatefulSet merupakan fitur stabil (GA) sejak versi 1. It has already been packaged into a docker. Here you can see how the Deployment itself runs a ReplicaSet that then runs 3 pods. 7) uses an update strategy to configure and disable automated rolling updates for containers, labels, resource request/limits, and annotations for its pods. kubectl create secret generic ceph-admin. The local persistent volumes feature reached general availability in Kubernetes 1. For a typical Kubernetes Pod, it will be managed by a higher-level controller like a Deployment. Administrators use deployments to specify what they want to happen with their applications. 9, so your version doesn't has support for it. io/pod-name: app-0. Example:Moreover, if at any point one of the replicas fails to start, the whole process will stop. They. Pods hold the containers for an application. A Deployment is a Kubernetes resource object used for declarative application updates. The example topology has a single primary server and multiple replicas, using asynchronous row-based replication. Like a Deployment, a StatefulSet. I have a cluster on gke with apache, mysql and keyrock and i would like to scale it up with horizontal pod autoscaler. Deployments. Diferencia entre Statefulset y Deployment en Kubernetes. kubectl get pods. This page shows how to run a replicated stateful application using a StatefulSet. For example, Kubernetes groups containers into units called pods,. Network identities: Kubernetes StatefulSet provides stable network identities for each pod, while Deployment doesn’t. sudo ceph auth get-key client. Use label selectors for get and delete operations instead of specific object names. The data persistence setup can be done with a VolumeClaimTemplate in the StatefulSet deployment. g. Get Full-Length High-Quality DevOps Tutorials for Free - Subscribe Now. Kubernetes Deployment vs StatefulSet. While Kubernetes StatefulSet offers a host of. The backing storage obviously must have ReadWriteMany or ReadOnlyMany accessMode if you have more than one replica pod. Atlantis should be up and running in minutes! See Next Steps for what to do next. If you’re writing your own operator to manage a Kubernetes application, here are some best. The Deployment creates a ReplicaSet that creates three replicated Pods, indicated by the. Overview of StatefulSets. The output of the describe command in this example is the following: Name: nginx-app1. StatefulSet and Deployment both aim to maximise availability, however StatefulSet is constrained by its inability to forgo data consistency (such as your state. I read a bit about Deployment vs StatefulSet in Kubernetes. In Kubernetes 1. Now that we have a basic understanding of a StatefulSet, let’s look at a sample StatefulSet deployment. Đây là bài thứ 9 trong series của mình, ở những bài trước chúng ta đã dùng Pod, ReplicaSet, Deployment để deploy một ứng dụng hoặc nhiều ứng dụng mà chạy chung một template để tăng performance. 23 introduced a new, alpha-level policy for StatefulSets that controls the lifetime of PersistentVolumeClaims (PVCs) generated from the StatefulSet spec template for cases when they should be deleted automatically when the StatefulSet is deleted or pods in the StatefulSet are scaled. For example, if you have named a StatefulSet as web, the pods will be named in the order of web-0, web-1, and so on till n minus one. StatefulSets are useful for managing stateful applications that require stable network identities and persistent. Once new pods are up (running and ready) it will terminate old pods. admin. Stateful app pods require unique identities because they communicate with other pods. Identities are defined as: - Network: A single stable DNS and hostname. A Kubernetes pod is a cluster deployment unit that typically contains one or more containers. Warning: In a cluster where not all users are trusted, a malicious user could. I want to deploy a single Pod on a Node to host my service (like GitLab for the example). Deployment vs StatefulSet component. Migrating stateful applications from deployment to statefulset is one of the best way to start getting feedback from users. PersistentVolumes and StatefulSets are the main approaches for running stateful applications in Kubernetes. 9, you can autoscale your statefulsets using: apiVersion: autoscaling/v1 kind: HorizontalPodAutoscaler metadata: name: YOUR_HPA_NAME spec: maxReplicas: 3. This is the first problem with the Kubernetes Deployment object for the stateful application. Thanks for the feedback. This feature can be used to upgrade the container images, resource requests and/or limits, labels, and annotations of the Pods in a StatefulSet. Both Deployment and StatefulSet try to maximize the availability - but StatefulSet cannot sacrifice data consistency (e. 2 Answers. 6 min read | by Jordi Prats. By default, Kubernetes uses the. The Reclaim Policy is used to determine the actions that need to be taken by the storage backend on deletion of the PV. ReplicaSet is a lower-level abstraction that provides basic scaling mechanisms. Deployments: It is used for “stateless applications”. Open this file in a code-editor and write the following code into it: apiVersion: apps/v1. It can appear that StatefulSet is a way to solve at most one instance in a situation with a network partition, but that is mostly in case of a stateful replicated application like e. Kubernetes Services: Pods exposed1 Answer. It provides declarative updates for pods and their. It is a Kubernetes resource, to manage stateful applications. The Deployment controller and Job controller are examples of controllers that come as part of Kubernetes itself ("built-in" controllers). Like a Deployment, a StatefulSet manages Pods that are based on an identical container spec. 7 and later, the StatefulSet controller supports automated updates. You can use StatefulSets to deploy stateful applications and clustered applications that save data to persistent storage, such as Compute Engine persistent. You can think of StatefulSet as the. Later it is open sourced, and today it’s one of the most active Apache projects. This creates a physical and logical grouping of your applications in Cluster. StatefulSetは状態を保持する (ステートフルな)アプリケーションを管理するためのKubernetesオブジェクトだ。. 5, we’ve moved the feature formerly known as PetSet into beta as StatefulSet. We’ll skip over this and go straight to the StatefulSet. This task shows how to scale a StatefulSet. One reason is that your coredns or kube-dns use dnsPolicy: Default and not the default dnsPolicy: ClusterFirst so changing it cluster-wide might affect your coredns/kube-dns pods. kubernetes. Feedback. Deployments vs Daemonsets vs Statefulsets. The Add Service settings appear. Then, the second pod (2) does likewise. Its main job is to manage containers. It is the default strategy when . Statefulset is a Kubernetes resource that handles pods that you need to hold a state. 其實是分別由以下三種資訊所組成：. A great deal of the work involved with creating a clustered environment of any type is the ability to deploy and scale with consistency. pod-1 can only read a subset of the data and write to a. It is mainly designed to use for stateful apps. Unlike a Deployment, a StatefulSet. StatefulSetには以下のような特徴がある。. When a StatefulSet's . As a pod can have one or more containers. To check your version of Kubernetes, run kubectl version. On-disk files in a Container are ephemeralStatefulSet is a Kubernetes controller used to deploy stateful apps. Melakukan proses manajemen deployment dan scaling dari sebuah set Pods, serta menjamin mekanisme ordering dan keunikan dari Pod ini. The StatefulSet controller provides each Pod with a unique hostname based on its ordinal index. svc. Deployment Spec vs StatefulSet SpecLet’s see how this works in practice with a MariaDB deployment in Kubernetes. It manages the deployment and scaling of a set of Pods, and provides guarantee about. StatefulSet. 0. When you use a StatefulSet, Kubernetes terminates Pods in the opposite order to their creation. After kubernetes 1. The Kubernetes manifest above is also deploying an Nginx application except for this time, you’ll see a few new pieces including: The kind is now StatefulSet; There are volumes; Mount paths exist to store the data; Let’s talk about the Deployment spec and StatefulSet differences. Author: Wei Huang (IBM), Aldo Culquicondor (Google) Managing Pods distribution across a cluster is hard. g. For example, to create and check a service configuration for an Nginx application, use the following: kubectl expose deployment/nginx-app1. Restart command will work as follows: After restart it will create new pods for a each deployments. If you want to delete just the StatefulSet and not the pods, use --cascade=false. ports: - protocol: TCP. Labels can be used to select objects and to find collections of. type: LoadBalancer. But many times, due to some requirements, users make sure that the pods are deployed in order with persistent storage volume and. In Elasticsearch, deployment is in clusters. StatefulSet (stable-GA in k8s v1. Deployment with Node Selector. Deployment is designed to create and manage a set of identical, independent, and replaceable copies of a pod. your state), so it cannot act as fast as Deployment (stateless) apps can. 9 sig-apps is expecting more feedback from the community with regards to statefulset. The solution(s) : Use a StatefulSet, ReplicaSet or DaemonSet to ensure the Pod creation after a Node failure. With a StatefulSet, your data can be stored on persistent volumes, decoupling the database application from the persistent storage, so when a pod (such as the database application) is recreated, all the. kubectl apply -f keycloak-sec. ; A Persistent Volume. It uses the same identity whenever it needs to reschedule those Pods. Let us see how StatefulSet differs from Deployment-1. StatefulSets are ideal for database deployments. StatefulSet is the workload API object used to manage stateful applications. The manifest files do not have the namespace added to them. If a Pod cannot be scheduled, the scheduler tries to preempt (evict) lower priority Pods to make scheduling of the pending Pod possible. system (system) Closed March 11, 2022, 6:44am 3. exe create deployment my-nginx --image nginx. How to use to kubectl to patch statefulset envFrom. yml └── keycloak-statefulset. StatefulSet is a controller in Kubernetes that allows users to manage pods the same as the deployments. zk-hs. A StatefulSet manages Pods that are based on an identical container spec. The stable hostname is generated from the name of the StatefulSet and the ordinal number of the pod in the set. The Prometheus Operator for Kubernetes provides easy monitoring definitions for Kubernetes services and deployment and management of Prometheus instances. yml service/redis-ss created. io/hostname" to deploy the redis cluster so that no two instances are located on the same host You can simply define three replicas of specific pod and define particular pod configuration file, egg. As we’ve seen, each pod in a StatefulSet gets assigned its. When you start a Deployment and specify a PVC, it will be shared by all pod replicas (if the volume is read-only). 💡Check out Kubernetes Deployments: The Ultimate Guide to understand more about how Deployments and ReplicaSets are used in a production setting. Like a Deployment, a StatefulSet manages Pods that are based on an identical container spec. Pods in StatefulSets are not interchangeable: each. Kubernetes is an open-source platform that automates the deployment, scaling, and management of containerized applications. There were no major changes to the API Object, other than the community selected name, but we added the semantics of “at most one. Manages the deployment and scaling of a set of Pods, and provides guarantees about the ordering and uniqueness of these Pods. 4. By default, the Kubernetes Scheduler could deploy more than one Pod in the zk StatefulSet to the same node. In the above YAML file, we have defined a simple StatefulSet to deploy a PostgreSQL database. Kubernetes Deployment and Helm are both tools used to manage applications in a Kubernetes environment. StatefulSet vs Deployment. The possible QoS classes are Guaranteed, Burstable, and. Its main purpose. Deployments. Key Concepts: Pods: The smallest deployable units in Kubernetes, consisting of one or more containers. StatefulSet. When deploying a Kubernetes application using the regular deployment and a ReplicaSet or a StatefulSet, you define the application as a Kubernetes Service, so other applications can interact with it. $ kubectl apply -f secret. Planning a Collector Deployment in Kubernetes. 1 Like. Use Cases of Kubernetes Stateful Application. When deploying a Kubernetes application using the regular deployment and a ReplicaSet or a StatefulSet, you define the application as a Kubernetes Service, so other applications can interact with it. StatefulSet is the controller that manages the deployment and scaling of a set of Stateful pods. StatefulSets are used when state has to be persisted. Metric name Metric type Description Labels/tags Status : kube_statefulset_annotations : Gauge : Kubernetes annotations converted to Prometheus labels controlled via --metric-annotations-allowlist Apache Cassandra is a distributed key-value store intended to run in a data center and also across multiple data centers. StatefulSet Kubernetes | Understand what StatefulSet in Kubernetes is and how it worksUsing StatefulSet in practice 🙅🏼♀️ This page describes the use of StatefulSet objects in Google Kubernetes Engine (GKE). We will then deploy a Kafka StatefulSet which uses our ZooKeeper cluster and also has Portworx volumes with 3 replicas. 9) is a Kubernetes resource used to manage stateful applications. g. 其實是分別由以下三種資訊所組成：. Totally agree with you i have been thinking about this recently as well, yes as a part of Kubernetes 1. For example, once a pod is running in your cluster. StatefulSets assign a sticky identity-an ordinal number starting from zero-to each Pod instead of assigning random IDs for each replica Pod. StatefulSet is the workload API object used to manage stateful applications. Deployments and ReplicationControllers are meant for stateless usage and are rather lightweight. A Kubernetes Deployment YAML specifies the configuration for a Deployment object—this is a Kubernetes object that can create and update a set of identical pods. Scaling a StatefulSet refers to increasing or decreasing the number of replicas. StatefulSet Kubernetes | Understand what StatefulSet in Kubernetes is and how it worksUsing StatefulSet in practice 🙅🏼♀️ page describes the use of StatefulSet objects in Google Kubernetes Engine (GKE). kubectl get pods NAME READY. In this exhaustive blog post, we will unravel these strategies layer by layer, backed by real-world scenarios and meticulously explained code examples. A StatefulSet is a controller that helps you deploy and scale groups of Kubernetes pods. cluster. It allows for controlled updates and seamless scaling, while maintaining the integrity of data and. StatefulSet merupakan salah satu objek API workload yang digunakan untuk aplikasi stateful. It provides features such as rolling updates, rollbacks, and scaling of the number of. Effective Kubernetes cluster management requires operations teams to balance pod and node deployments with performance and availability needs. We will also see how to set up the MongoDB administrator for a container that runs under a cluster. Was this page helpful? Yes No. A StatefulSet is a workload API object for managing stateful applications. Author: Deepak Kinni (VMware) PersistentVolume (or PVs for short) are associated with Reclaim Policy. We’ll add the key as a secret in Kubernetes. What you generally should do is not to write the manifests for a MySQL deployment yourself. StatefulSet is a Kubernetes controller that manages multiple pods that have unique identities, and are not interchangeable (unlike a regular Kubernetes Deployment, in which pods are stateless and. This topic was automatically closed 28 days after the. yaml. For any other case, it’s recommended that you use a Deployment. As opposed to the Deployment, the StatefulSet creates pods directly. ReplicaSet vs. yaml kubectl apply -f statefulset. This is different from vertical scaling, which for Kubernetes would. The concept of a pod in Kubernetes makes it easy to tag multiple containers that are treated as a single unit of deployment. If your application is stateless, you should use Deployment and not StatefulSet. As of Kubernetes v1. Deploy the workloads on kubernetes. There are a few differences between StatefulSet and Deployment in Kubernetes, including: Ordering: Kubernetes StatefulSet ensures that each pod is. Using these replicas, we can have fast failover of the Kafka nodes and eliminate the I/O load during. A DeploymentConfig (DC) in OpenShift is more or less equivalent to a Kubernetes Deployment, nowadays. Al igual que un Deployment, un StatefulSet gestiona Pods que se basan en una especificación idéntica de contenedor. A Kubernetes secret for storing the database password. After reading thru Kubernetes documents like this, deployment, service and this I still do not have a clear idea what the purpose of service is. The difference between StatefulSets and Deployments reflects the divide between stateful and stateless systems. metadata. Unlike a Deployment, a StatefulSet. Main difference (besides that one is using ReplicationController and the other using ReplicaSet as you rightly pointed out) is that. Each pod has a persistent identifier, that it maintains across any. As the world becomes increasingly digital, companies are turning to cloud-based solutions like Kubernetes to help manage their applications. So by passing this flag to kubectl delete the Pods that are managed by. Share. Each Pod has init and main container. Despite both controllers being instrumental in managing high-availability. Before understanding StatefulSets, you must understand Kubernetes Deployment. You must create volumes within Kubernetes in order for your PVCs to use them. apiVersion: apps/v1 kind: StatefulSet # < kind of installation (statefulset vs Deployment) metadata: name: nextcloud-db # < name of the deployment namespace: nextcloud # < namespace where to place the statefulset and pods labels: app: nextcloud # < label for tagging and reference spec: serviceName: nextcloud-db-service # < name of. Unlike the average Kubernetes pods, pods within a StatefulSet have a unique index and a stable network identity that is published through a Headless Service. Regarding HA configuration of Eureka in Kubernetes: You can (meanwhile) use a StatefulSet for this instead of creating a service for each instance. In a stateful containerized application, data must be persistent, retained and easy to access outside the application. Ordered, graceful deployment and scaling. We will make use of Kubernetes persistence and claims. replicas is not equal to status.