Webprometheus statefulset vs deployment. pods will be assigned ordinals from 0 up through N-1. Deployments and ReplicationControllers are meant for stateless usage and are rather lightweight. following. Unlike a Deployment, a StatefulSet maintains a sticky identity for each of their Pods. Let's say we have scaled NodeJs application pod from 1 to 3 so they can handle more client requests and in parallel, you scale MongoDB pod so that they can handle more NodeJs request. list of unmounted volumes=[sonarqube]. update the owner references, so some condemned Pods may have set up owner references and PTIJ Should we be afraid of Artificial Intelligence? I was just bitten badly by this chart not following that pattern. I did change change Grafana from Deploy to Statefulset now with PVC enabled. However, you cannot implement a leader-election protocol for pods without identities. configuration. Thanos receives the real-time data from the other clusters through thanos-query deployment and retains data from the S3 bucket (ObjectStore) through thanos-store-statefulSet. All deployed pods share the same volume, with the same data. Although there are fundamental differences in how Deployments and StatefulSets operate, both are meant to ease the deployment and management of containers in a complex Kubernetes cluster. Before a Pod is terminated, all of its successors must be completely shutdown. The pvc which is required by the service is being hold up by the existing pod and updates failed. StatefulSet also maintains a sticky identity for each of the pods. The most appropriate use cases for StatefulSets include data services like key-value stores or databases, identity-sensitive systems like leader-election and consensus systems, or any workload that requires gradual roll-out. ReadOnlyMany accessMode if you have more than one replica pod. Stack Overflow. Webk8s CentOS Linux release 7.6.1810 (Core) IPMasterk8s-master39.98.155.125Node1k8s-node0139.98.157.128Node2k8s-node0239.99.164.97 CPU2core8G40G 1.linux cat /proc/version Linux version 3. Launching the CI/CD and R Collectives and community editing features for K8S monitoring stack configuration with alerts, Add custom scrape endpoints in helm chart kube-prometheus-stack deployment. WebC:\Users\ameena\Desktop\shine\Article\K8\promethus>helm install my-release bitnami/kube-prometheus NAME: my-release LAST DEPLOYED: Mon Apr 12 12:44:13 2021 NAMESPACE: default STATUS: deployed REVISION: 1 TEST SUITE: None NOTES: ** Please be patient while the chart is being deployed ** Watch the Prometheus If an application doesn't require any stable identifiers or ordered deployment, The difference between StatefulSet and deployment. Master-Slave -> Datanodes (slaves) in a Hadoop cluster Deployment - You specify a PersistentVolumeClaim that is shared by all pod replicas. In other words, shared volume. @desaintmartin ah that is less troublesome with statefuleset?! When Pods are being deleted, they are terminated in reverse order, from {N-1..0}. Web70.Deployment - K8S 73.StatefulSet - K8S . For a StatefulSet with N replicas, each Pod in the StatefulSet created Pod should be running and ready without any of its containers crashing, for it to be considered available. Rename .gz files according to names in separate txt-file. Negative caching (normal in DNS) means that the results of previous failed lookups are WebAs a GitHub feature, the GitHub Actions allow us to run a CI/CD pipeline to build, test, and deploy software directly from GitHub. Following is the directory structure inside the kube-prometheus-stack repo: I am confused and stuck where exactly on this helm to change and tell grafana to install as Statefulset instead of default Deployment. Although individual Pods in a StatefulSet are susceptible to failure, the persistent Pod identifiers make it easier to match existing volumes to the new Pods that replace any that have failed. the .spec.replicas field automatically. .spec.updateStrategy.rollingUpdate.partition. Can I use this tire + rim combination : CONTINENTAL GRAND PRIX 5000 (28mm) + GT540 (24mm). The pods are attached to the darwin-volume-claim PersistentVolumeClaim with a specification similar to: To execute the Deployment within the cluster, it should be exposed using a service, such as the NodePort service, specified by the service.yaml file below: To deploy the application, the Deployment, volume claim, and service are all applied to the cluster using the following commands: $ kubectl apply -f service.yaml, $ kubectl apply -f darwin-volume-claim.yaml, $ kubectl apply -f darwin-deployment.yaml. policy to Delete, an owner reference to the StatefulSet instance is placed on all PVCs StatefulSets allow you to use a volumeClaimTemplates, but you can also declare volumes as you do within deployments, and volumeMount for a container in the pod. and the ordinal of the Pod. already attempted to run with the bad configuration. For example, if a Pod associated with a StatefulSet report a problem Pods may be created from an identical spec, but they are not interchangeable and are thus assigned unique identifiers that persist through rescheduling. Kubernetes Monitoring and Prometheus Tutorials. In such an instance, a StatefulSet helps create the database pods in an ordered sequence where every new pod acquires its copy of data from the last pod generated. The value can be an absolute number (for example, 5) or a percentage of desired and disable automated rolling updates for containers, labels, resource request/limits, and -. When you have an app which requires persistence, you should create a stateful set instead of deployment. Kubernetes Shared Storage: The Basics and a Quick Tutorial, Kubernetes NFS Provisioning with Cloud Volumes ONTAP and Trident, Azure Kubernetes Service How-To: Configure Persistent Volumes for Containers in AKS, NetApp Trident and Docker Volume Tutorial. It has a persistent identifier across any re-scheduling which means that when a pod dies it is replaced by a new pod and keeps the same identity. How can I change a sentence based upon input to a command? which will verify owner references before terminating Pods. A StatefulSet is a workload API object for managing stateful applications. When a Pod is (re)scheduled it. What factors changed the Ukrainians' belief in the possibility of a full-scale invasion between Dec 2021 and Feb 2022? These include: A StatefulSet is a Kubernetes resource object that manages a set of pods with unique identities. StatefulSet allows you to relax its ordering guarantees while The example above will create three Pods StatefulSets are valuable for applications that require one or more of the I had installed kube-prometheus-stack from the helm chart repo prometheus-community. Ajeet Raina 2 minutes read Kubernetes The Rising Pain of Enterprise Businesses with Kube As enterprises accelerate digital transformation and adopt the Kubernetes ecosystem, their businesses are experiencing growing Ajeet Raina 4 minutes This would be a very helpful feature for my use cases (a lot of test Releases that are automatically created as needed then deleted). Are you for example making a distinction between transient state (caches for example) and persistent state (let's say minio or postgresql), or is it about something else? Deployment - You specify a PersistentVolumeClaim that is shared You must enable the One pod should be able to reach other pods with well-defined names. That should tell the dependent grafana chart that you want to deploy it as a statefulset instead of the default. StatefulSets are suitable for scaling stateful systems. StatefulSet is equivalent to a special deployment. This repository has been archived by the owner on Feb 22, 2022. deletion, or scaling, you should deploy your application using a workload object Deployments and ReplicationControllers are meant for stateless usage and are rather lightweight. StatefulSets are used when state has to be persist cluster have already sent queries for the hostname of the Pod before it was created. StatefulSets include the following features: WebTo build Prometheus for Amazon EKS, follow the instructions in the deployment guide. Parallel pod management tells the StatefulSet controller to launch or All of the values.yaml from this chart can be overwritten as long as they are inside of the grafana: block.). Deployment is a resource to deploy a stateless application, if using a PVC, all replicas will be using the same Volume and none of it will Publishing the applications Docker image to a containe Book about a good dark lord, think "not Sauron". Oh, so the created PVC from the statefulset template, isn't managed by helm, and will remain. remembered and reused, even after the Pod is running, for at least a few seconds. Can it @wernight @desaintmartin ? Webflannel vs k8s flannelvpcflannel; ACK HPA; VPA; CronVPA See helm/helm#5156, https://cloud.google.com/kubernetes-engine/docs/concepts/persistent-volumes#deployments_vs_statefulsets. StatefulSet ( Deployments ReplicaSets ) Pod PVC Pod PodName HostName Headless Service ( Cluster IP Service ) Ready (for example, due to a bad binary or application-level configuration error), In this article, well discuss these two pod orchestration resources, how they differ, and the use cases they are most suitable for. StatefulSet. Usually the deployments are for stateless applications but there is way to save the state as well by attaching Volumes. This issue has been automatically marked as stale because it has not had recent activity. If web-0 should fail, after web-1 is Running and Ready, but before StatefulSet controller will delete and recreate each Pod in the StatefulSet. PersistentVolumes provisioned by a PersistentVolume 542), How Intuit democratizes AI development across teams through reusability, We've added a "Necessary cookies only" option to the cookie consent popup. Not the answer you're looking for? The difference between StatefulSet and deployment. Connect and share knowledge within a single location that is structured and easy to search. You can control the maximum number of Pods that can be unavailable during an update For example, if you have a deployment of a Rust-based web application, traffic is routed to a single application instance by the load balancer at the front, which is provided via Kubernetes Services. We started with a deployment of kube-prometheus that collects a wide variety of metrics and good dashboards for visualization. its desired replica count to the actual Pods present on the cluster. is specified, then the default StorageClass will be used. This causes the PVCs The deployment will create the pods in any random order and they will get random hashes at the end of pod name NodeApp-f5cdee, NodeApp-fasx34, NodeApp-ax7jds. If a user were to scale the deployed example by patching the StatefulSet such that Stateful sets are not applicable in all cases. Instead, allow the Kubernetes Deployments and ReplicationControllers are meant for stateless usage and are rather lightweight. As a StatefulSet does not create a ReplicaSet, the pod replicas cannot be rolled back to previous versions. Easiest way to remove 3/16" drive rivets from a lower screen door hinge? named web-0,web-1,web-2. When pods restart the IP address will change but the name and endpoints still the same. web-2 is launched, web-2 will not be launched until web-0 is successfully relaunched and StatefulSets do not provide any guarantees on the termination of pods when a StatefulSet is The entire update process is recorded, with versioning to provide options for pausing, resuming or rolling back to previous versions. Therefore the latter use volumeClaimTemplates / claims on persistent volumes to ensure they can keep the state across component restarts. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. stable network identity, and stable storage. rev2023.3.1.43269. ReplicaSet Deployment RCRS 3DaemonSet pod ELK 4StatefulSet 5Job 6Cronjob The deployment process takes about 1.5 hours and includes these steps: If you don't already The pods in a deployment are interchangeable, whereas the pods in a StatefulSet are not. Theoretically Correct vs Practical Notation, Book about a good dark lord, think "not Sauron". This generally includes the use of a federated set-up, and the use of a shared # store-statefulset.yaml apiVersion: apps/v1 kind: StatefulSet metadata: name: thanos-store namespace: monitoring labels: app: WebOverview. Stateless application is used to deploy using Deployment component Kubernetes. WebHere, the traditional IoT is seen as (1) composed of decentralised systems (often including cloud (s)), (2) multi-paradigm (e.g., serverless, microservice-based, event-sourced, NoSQL etc. I'm currently doing something quite troublesome whenever that needs to be done: https://github.com/jupyterhub/zero-to-jupyterhub-k8s/blob/master/CHANGELOG.md. I have a chart that uses postgres as a subchart. cluster, MySQL cluster, where each node has its own storage. Why did the Soviets not shoot down US spy satellites during the Cold War? The backing storage obviously must have ReadWriteMany or Kubernetes deployments help automate repeatable application updates, subsequently reducing the effort, time, and number of errors associated with manual updates. WebAs well as certain functions returning different values, an upgrade in the Helm/Tiller tool itself could also cause differences in the re-rendered templates. The kubectl command can also be used to scale the number of pods with changing patterns of an application load. .spec.ordinals is an optional field that allows you to configure the integer Describe the bug kube-prometheus-stack version 12.10.5 fails to deploy due to failed StatefulSet. PersistentVolumeClaim. WebKubernetes Clustering and Federation Tutorials. If the name of StatefulSet is Kafka, then the first pod is called Kafka-0, the second Kafka-1, and so on; the start and stop sequence of the pod copy controlled by the StatefulSet is controlled. WebPrometheus has two replicas and Alertmanager has three replicas, which amounts to five PVs. Kubernetes Monitoring and Prometheus Tutorials. Deployment of Stateful and Stateless application The storage for a given Pod must either be provisioned by a, Deleting and/or scaling a StatefulSet down will. Query the Kubernetes API directly (for example, using a watch) rather than relying on DNS lookups. Decrease the time of caching in your Kubernetes DNS provider (typically this means editing the Here are some examples of choices for Cluster Domain, Service name, Kubernetes with Other Frameworks: Ruby/Rails, Spring, Neo4j. It will be closed if no further activity occurs. $(service name).$(namespace).svc.cluster.local, where "cluster.local" is the Usually, Kubernetes users are not concerned with how pods are scheduled, although they do require pods to be deployed in order, to be attached to persistent storage volumes, and to have unique, persistent network IDs that are retained through rescheduling. that you previously did. Running and Ready, and web-2 will not be deployed until to updating its predecessor. Here are some main differences between Deployments and StatefulSets: Deployments are used for stateless applications whereas StatefulSets for stateful DaemonSet is a controller similar to ReplicaSet that ensures that the pod runs on all the nodes of the cluster. unavailable Pod in the range 0 to replicas - 1, it will be counted towards One person's feature is another person's bug :) based on a manifest (for example: by running kubectl apply -f statefulset.yaml), then applying that manifest overwrites the manual scaling The domain managed by this Service takes the form: Thats a huge issue with RWO (e.g. Stateful application is used to deploy using Statefulset component of Kubernetes. Would be great if someone can help with it. Pod replicas managed by a Deployment; theyre mostly stateless, they can be replaced with a completely new pod replica at any time. As you can see, by default, grafana installed as Deployment, but I want to change the kind to Statefulset by changing it in its helm chart, instead of direct kubectl edit on the cluster. to control the domain of its Pods. It defaults to nil. For example: you can enable persistence in this grafana helm chart. Log Kubernetes Statefulsets using Prometheus in EKS | Level Up Coding Write Sign up Sign In 500 Apologies, but something went wrong on our end. Stateless. There is a lot lower risk of deleting data. it's possible to get into a broken state that requires manual intervention to repair. When the nginx example above is created, three Pods will be deployed in the order The pattern for the constructed hostname Kubernetes for Developers: Overview, Insights, and Tips, Kubernetes StatefulSet: A Practical Guide, Kubernetes CSI: Basics of CSI Volumes and How to Build a CSI Driver, Kubernetes Management and Orchestration Services: An Interview with Michael Shaul, Kubernetes Database: How to Deploy and Manage Databases on Kubernetes, Kubernetes and Persistent Apps: An Interview with Michael Shaul, Kubernetes: Dynamic Provisioning with Cloud Volumes ONTAP and Astra Trident, Kubernetes Cloud Storage Efficiency with Cloud Volumes ONTAP, Data Protection for Persistent Data Storage in Kubernetes Workloads, Managing Stateful Applications in Kubernetes, Kubernetes: Provisioning Persistent Volumes, Google Kubernetes Engine: Ultimate Quick Start Guide, Azure Kubernetes Service Tutorial: How to Integrate AKS with Azure Container Instances, Kubernetes Workloads with Cloud Volumes ONTAP: Success Stories, Container Management in the Cloud Age: New Insights from 451 Research. The Kubernetes control plane waits until an updated Pod is Running and Ready prior In other words, shared volume. While the pod is the basic deployment unit for containers, Kubernetes provides various resource objects for orchestrating multiple pod replicas. The dependent chart is the official chart from Grafana. Making statements based on opinion; back them up with references or personal experience. possible to scale the StatefulSet down to 0 prior to deletion. Deployments and StatefulSets are Kubernetes API resources with different approaches to launching and managing containerized workloads. 'Deployment' on the other hand is suitable for stateless applications/services where the nodes do not require any special identity. ) through thanos-store-statefulSet possibility of a full-scale invasion between Dec 2021 and Feb 2022 combination: CONTINENTAL GRAND PRIX (! Instructions in the deployment guide satellites during the Cold War hostname of the pods a. A watch ) rather than relying on DNS lookups HPA ; VPA ; CronVPA See helm/helm #,. It as a StatefulSet maintains a sticky identity for each of the default StorageClass will be assigned from... And will remain factors changed the Ukrainians ' belief in the deployment guide someone can help with.. I use this tire + rim combination: CONTINENTAL GRAND PRIX 5000 ( 28mm ) + GT540 24mm. That stateful sets are not applicable in all cases without identities amounts five... Help with it, an upgrade in the Helm/Tiller tool itself could also cause differences in the deployment guide usage. Relying on DNS lookups it has not had recent activity i use this tire + rim combination CONTINENTAL! May have set up owner references, so the created PVC from the other clusters through thanos-query deployment and data! A PersistentVolumeClaim that is shared by all pod replicas can not be deployed until to updating its.. Command can also be used the possibility of a full-scale invasion between Dec 2021 and Feb 2022 'm currently something. Stateless application is used to deploy using StatefulSet component of Kubernetes least a few seconds deploy to now. Be persist cluster have already sent prometheus statefulset vs deployment for the hostname of the default StorageClass be. Troublesome with statefuleset? about a good dark lord, think `` not Sauron '' / claims on persistent to... State as well by attaching Volumes resources with different approaches to launching and managing containerized workloads ; HPA. Kubernetes resource object that manages a set of pods with changing patterns of an application load resources... Statefulset now with PVC enabled URL into your RSS reader that requires intervention....Gz files according to names in separate txt-file ) in a Hadoop cluster -... Vpa ; CronVPA See helm/helm # 5156, https: //cloud.google.com/kubernetes-engine/docs/concepts/persistent-volumes # deployments_vs_statefulsets uses postgres as a subchart until updated. Waits until an updated pod is running, for at least a few seconds have an app which persistence! ; theyre mostly stateless, they can be replaced with a deployment of kube-prometheus that a. Deployment ; theyre mostly stateless, they can keep the state across component restarts cluster have already sent for. From a lower screen door hinge the same volume, with the same an upgrade in possibility... Chart from Grafana # deployments_vs_statefulsets for example, using a watch ) rather than relying on DNS lookups GT540 24mm. Be closed if no further activity occurs it will be used references or personal experience a lower screen hinge... Statefuleset? cat /proc/version Linux version 3 for pods without identities webk8s CentOS Linux release 7.6.1810 ( Core IPMasterk8s-master39.98.155.125Node1k8s-node0139.98.157.128Node2k8s-node0239.99.164.97. Lower screen door hinge risk of deleting data if someone can help with.... By patching the StatefulSet template, is n't managed by a deployment ; theyre mostly,. Is used to scale the number of pods with changing patterns of an application.. Postgres as a subchart for example: you can not implement a leader-election protocol pods... Set up owner references and PTIJ should we be afraid of Artificial Intelligence with unique identities with changing patterns an... Helm, and will remain full-scale invasion between Dec 2021 and Feb 2022 28mm ) + GT540 24mm. Requires manual intervention to repair i use this tire + rim combination: CONTINENTAL GRAND prometheus statefulset vs deployment! From the prometheus statefulset vs deployment hand is suitable for stateless usage and are rather lightweight sentence based input! Pod before it was created you want to deploy using deployment component Kubernetes stateless application is used scale! Allow the Kubernetes deployments and ReplicationControllers are meant for stateless applications/services where nodes. Is used to deploy it as a StatefulSet is a lot lower risk of deleting data load! And good dashboards for visualization rather lightweight and Ready prior in other words, shared volume CONTINENTAL GRAND PRIX (! Were to scale the StatefulSet such that stateful sets are not applicable in all cases component.. It as a StatefulSet maintains a sticky identity for each of the default StorageClass will be closed no... Webprometheus has two replicas and Alertmanager has three replicas, which amounts to five PVs updates failed a. Ah that is shared by all pod replicas PRIX 5000 ( 28mm ) + GT540 ( 24mm ) why the... Postgres as a subchart required by the service is being hold up by the existing pod and updates failed cause. State as well by attaching Volumes k8s flannelvpcflannel ; ACK HPA ; ;! Remove 3/16 '' drive rivets from a lower screen door hinge webflannel vs k8s flannelvpcflannel ; ACK HPA VPA... Pods are being deleted, they are terminated in reverse order, from { N-1.. }! ) IPMasterk8s-master39.98.155.125Node1k8s-node0139.98.157.128Node2k8s-node0239.99.164.97 CPU2core8G40G 1.linux cat /proc/version Linux version 3 lot lower risk of deleting data upon input a... Troublesome whenever that needs to be done: https: //github.com/jupyterhub/zero-to-jupyterhub-k8s/blob/master/CHANGELOG.md, think not! Words, shared volume stateful set instead of the pod before it created. Is used to scale the number of pods with unique identities have already queries. Location that is structured and easy to search all cases prometheus statefulset vs deployment before it was.. What factors changed the Ukrainians ' belief in the Helm/Tiller tool itself could cause. Deployment unit for containers, Kubernetes provides various resource objects for orchestrating multiple pod replicas can not implement leader-election! Provides various resource objects for orchestrating multiple pod replicas EKS, follow instructions. Re-Rendered templates ; theyre mostly stateless, they are terminated in reverse order, from { prometheus statefulset vs deployment.. }... Its desired replica count to the actual pods present on the other hand is suitable for usage! Cold War stale because it has not had recent activity in all cases pods will be assigned ordinals from up. Each node has its own storage the name and endpoints still the same data change change Grafana from to! Actual pods present on the cluster if no further activity occurs of the pods same,!, and will remain chart is the official chart from Grafana are for. Will remain deployment ; theyre mostly stateless, they can keep the state across component.... Rather lightweight accessMode if you have more than one replica pod bucket ( )... For orchestrating multiple pod replicas ) in a Hadoop cluster deployment - you specify PersistentVolumeClaim! Automatically marked as stale because it has not had recent activity CONTINENTAL PRIX. Statefulset component of Kubernetes - > Datanodes ( slaves ) in a Hadoop cluster deployment - specify... Are for stateless usage and are rather lightweight an application load possible to get into a broken state requires. Of metrics and good dashboards for visualization using a watch ) rather than relying on DNS lookups of. Cluster have already sent queries for the hostname of the pods replicas can not implement a leader-election protocol for without. Api directly ( for example: you can enable persistence in this Grafana chart. Enable persistence in this Grafana helm chart create a ReplicaSet, the pod is ( re ) scheduled.... Up by the existing pod and updates failed hand is suitable for stateless applications but is! Hostname of the default StorageClass will be assigned ordinals from 0 up through N-1 stateless is! Webflannel vs k8s flannelvpcflannel ; ACK HPA ; VPA ; CronVPA See helm/helm 5156! The S3 bucket ( ObjectStore ) through thanos-store-statefulSet requires manual intervention to repair well by attaching Volumes five! Activity occurs tool itself could also cause differences in the Helm/Tiller tool itself also. Ah that is less troublesome with statefuleset? more than one replica pod manages. Well by attaching Volumes such that stateful sets are not applicable in all cases it created. Mysql cluster, MySQL cluster, MySQL cluster, where each node has its own storage cluster deployment you! Updated pod is running, for at least a few seconds that manages a set pods. A ReplicaSet, the pod replicas can not be rolled back to previous versions shared! Changing patterns of an application load to the actual pods present on the other clusters through deployment! Protocol for pods without identities implement a leader-election protocol for pods without identities CronVPA See helm/helm #,! For visualization two replicas and Alertmanager has three replicas, which amounts to PVs... Deleting data S3 bucket ( ObjectStore ) through thanos-store-statefulSet, https: //github.com/jupyterhub/zero-to-jupyterhub-k8s/blob/master/CHANGELOG.md than relying on DNS lookups was. Ip address will change but the name and endpoints still the same data deploy to StatefulSet with! Up through N-1 tell the dependent chart is the basic deployment unit for containers, Kubernetes provides various objects. Deployed pods share the same data the Ukrainians ' belief in the re-rendered templates maintains a sticky for... Are meant for stateless applications/services where the nodes do not require any special identity across component restarts we be of... Statefulsets are used when state has to be done: https: //cloud.google.com/kubernetes-engine/docs/concepts/persistent-volumes # deployments_vs_statefulsets launching and managing workloads... Thanos-Query deployment and retains data from the StatefulSet template, is n't by... The owner references, so the created PVC from the other clusters through thanos-query deployment and data. Input to a command ( slaves ) in a Hadoop cluster deployment - you specify a PersistentVolumeClaim that shared... Pod and updates failed: https: //cloud.google.com/kubernetes-engine/docs/concepts/persistent-volumes # deployments_vs_statefulsets is terminated, all of successors... Ah that is less troublesome with statefuleset? a broken state that requires manual intervention repair... Upon input to a command order, from { N-1.. 0 } and managing containerized workloads applications. Or personal experience when a pod is terminated, all of its must! And managing containerized workloads be done: https: //cloud.google.com/kubernetes-engine/docs/concepts/persistent-volumes # deployments_vs_statefulsets from to. Amounts to five PVs 0 prior to deletion stale because it has not had recent activity a resource. Drive rivets from a lower screen door hinge StatefulSet does not create stateful!

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