Containarized Gluster Storage in Kubernetes

Containarized Gluster Storage in Kubernetes

• 1.
  Gluster Storage inKubernetes Saravanakumar Arumugam 25 August 2018 Joint meetup by: Docker and Kubernetes community, Bangalore
• 2.
  2 Agenda ● GlusterFS Storage ●Kubernetes Storage Concepts ● GlusterFS in Kubernetes ● Demo
• 3.
  ● Scale-out distributedstorage system. ● Aggregates storage exports over network interconnects to provide an unified namespace. ● Layered on disk file systems that support extended attributes. ● Provides file, object and block interfaces for data access. GlusterFS
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  GlusterFS Demo
• 5.
  5 Openshift (Kubernetes) OpenShift -Enterprise Kubernetes for Developers Openshift Container Platform(OCP) is Red Hat’s PaaS offering that offers customers a full stack platform for creating/maintaining micro-services. Upstream: https://github.com/openshift/origin
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  PODPOD containers are wrappedin pods which are units of deployment and management 6 CONTAINER CONTAINERCONTAINER IP: 10.1.0.11 IP: 10.1.0.55
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  pods configuration isdefined in a deployment 7 image name replicas labels cpu memory storage POD CONTAINER POD CONTAINER POD CONTAINER DEPLOYMENT
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  POD services provide internalload-balancing and service discovery across pods 8 CONTAINER POD CONTAINER POD CONTAINER BACKEND SERVICE POD CONTAINER role: backend role: backendrole: backendrole: backendrole: frontend
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  POD apps can talkto each other via services 9 CONTAINER POD CONTAINER POD CONTAINER BACKEND SERVICE POD CONTAINER role: backend role: backendrole: backendrole: backendrole: frontend Invoke Backend API
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  POD routes add servicesto the external load-balancer and provide readable urls for the app 10 CONTAINER POD CONTAINER POD CONTAINER BACKEND SERVICE ROUTE app-prod.mycompany.com > curl http://app-prod.mycompany.com
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  projects isolate appsacross environments, teams, groups and departments 11 POD C POD C POD C PAYMENT DEV POD C POD C POD C PAYMENT PROD POD C POD C POD C CATALOG POD C POD C POD C INVENTORY ❌ ❌❌
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  ● What areContainers and images, and how are they different ○ Image = Binary Artifact ○ Container = Running Instantiation of an image ● What are Pods, Services, Route ○ Pods are the baseline unit, used in defining an application or process ○ Services are discovery/routing objects used to interact with pods/containers ○ Routes are for external world to access the pods. ● What is a Project/Namespace ○ A logical grouping / workspace for resources ○ Aso acts as an isolation boundary for networking and permissions Recap..
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  Containers are ephemeralby nature, but many applications require storage that is persistent beyond the life cycles of the application containers. Use cases: ● persistent storage for application containers ● Registry Storage in containers
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  ● StorageClass ● PVC- PersistentVolumeClaim ● PV - PersistentVolume Some more at background: ● Provisioner ● Mount plugin Storage concepts in Kubernetes
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  ● created byadmin ● describes the storage ● references a (dynamic) provisioner Example: https://github.com/gluster/gluster-kubernetes/blob/master/deploy/kube-templates/gluster-s3-s torageclass.yaml#L2 StorageClass
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  - created byuser - references Storageclass - says which provisioner to use ( answer: glusterfs) Example: https://github.com/gluster/gluster-kubernetes/blob/423b0c4d50e299e8f 429a5a820ba0389e365d005/deploy/ocp-templates/gluster-s3-pvcs.ya ml#L5 PersistentVolumeClaim - PVC
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  ReadWriteOnce RWO The volumecan be mounted as read-write by a single node. ReadOnlyMany ROX The volume can be mounted read-only by many nodes. ReadWriteMany RWX The volume can be mounted as read-write by many nodes. Access modes in PVC
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  ● when usercreates a PVC(with storageclass referenced) PV is created. ● PV is the actual volume to be mounted in the application. ● PV is bound to PVC. ❖ Creating PVC automatically creates PV. ❖ The PVC controls the lifecycle of the storage, not the PV. PersistentVolume - PV
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  Workflow PVC (Size) PV User Admin StorageClass
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  The workflow fordynamically provisioning storage is as follows: 1. An administrator sets up some storage, then defines a storage class (SC) that describes the storage. 2. A user creates a persistent volume claim (PVC) to request some storage of a given size, access type, and SC 3. A persistent volume (PV) is dynamically created of the requested size on some storage that matches the SC. 4. The matched PV is then bound to the PVC and can be used by the user in pods. The data in the PV persists beyond the lifecycle of the pod. When the PVC is deleted, the PV is released. Lifecycle of Volume creation
• 21.
  Demo
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  Gluster-Kubernetes https://github.com/gluster/gluster-kubernetes Gluster containers https://github.com/gluster/gluster-containers GlusterFS https://github.com/gluster/glusterfs Credits to: GlusterFS and OpenShift Community References:
• 23.
  Thank you! https://github.com/SaravanaStorageNetwork