Installing Che using storage classes

To configure Che to use a configured infrastructure storage, install Che using storage classes. This is especially useful when a user wants to bind a persistent volume provided by a non-default provisioner. To do so, a user binds this storage for the Che data saving and sets the parameters for that storage. These parameters can determine the following:

A special host path
A storage capacity
A volume mod
Mount options
A file system
An access mode
A storage type
And many others

Che has two components that require persistent volumes to store data:

A PostgreSQL database.
A Che workspaces. Che workspaces store source code using volumes, for example /projects volume.

Che workspaces source code is stored in the persistent volume only if a workspace is not ephemeral.

Persistent volume claims facts:

Che does not create persistent volumes in the infrastructure.
Che uses persistent volume claims (PVC) to mount persistent volumes.
The Che server creates persistent volume claims.

A user defines a storage class name in the Che configuration to use the storage classes feature in the Che PVC. With storage classes, a user configures infrastructure storage in a flexible way with additional storage parameters. It is also possible to bind a static provisioned persistent volumes to the Che PVC using the class name.

Procedure

Use CheCluster Custom Resource definition to define storage classes:

Define storage class names

To do so, use one of the following methods:
- Use arguments for the server:start command
  1. Provide the storage class name for the PostgreSQL PVC
    
    Use the chectl server:start command with the --postgres-pvc-storage-class-name flag:
    
    $ chectl server:start -m -p minikube -a operator --postgres-pvc-storage-class-name=postgress-storage
  2. Provide the storage class name for the Che workspaces
    
    Use the server:start command with the --workspace-pvc-storage-class-name flag:
    
    $ chectl server:start -m -p minikube -a operator --workspace-pvc-storage-class-name=workspace-storage
    
    For Che workspaces, the storage class name has different behavior depending on the workspace PVC strategy.
    
    postgres-pvc-storage-class-name=postgress-storage and workspace-pvc-storage-class-name work for the Operator installer and the Helm installer.
- Define storage class names using a Custom Resources YAML file:
  1. Create a YAML file with Custom Resources defined for the Che installation.
  2. Define fields: spec#storage#postgresPVCStorageClassName and spec#storage#workspacePVCStorageClassName.
    
    apiVersion: org.eclipse.che/v1 kind: CheCluster metadata: name: eclipse-che spec: # ... storage: # ... # keep blank unless you need to use a non default storage class for PostgreSQL PVC postgresPVCStorageClassName: 'postgres-storage' # ... # keep blank unless you need to use a non default storage class for workspace PVC(s) workspacePVCStorageClassName: 'workspace-storage' # ...
  3. Start the che server with your Custom Resources:
    
    $ chectl server:start -m -p minikube -a operator --che-operator-cr-yaml=/path/to/custom/che/resource/org_v1_che_cr.yaml

Configure Che to store workspaces in one persistent volume and a PostreSQL database in the second one:

Modify your Custom Resources YAML file:

Set pvcStrategy as common.
Configure Che to start workspaces in a single namespace.
Define storage class names for postgresPVCStorageClassName and workspacePVCStorageClassName.

Example of the YAML file:

apiVersion: org.eclipse.che/v1
kind: CheCluster
metadata:
  name: eclipse-che
spec:
  server:
    # ...
    workspaceNamespaceDefault: 'che'
    # ...
  storage:
    # ...
    # Defaults to common
    pvcStrategy: 'common'
    # ...
    # keep blank unless you need to use a non default storage class for PostgreSQL PVC
    postgresPVCStorageClassName: 'postgres-storage'
    # ...
    # keep blank unless you need to use a non default storage class for workspace PVC(s)
    workspacePVCStorageClassName: 'workspace-storage'
    # ...

Start the che server with your Custom Resources:

$ chectl server:start -m -p minikube -a operator --che-operator-cr-yaml=/path/to/custom/che/resource/org_v1_che_cr.yaml

Bind static provisioned volumes using class names:

Define the persistent volume for a PostgreSQL database:

# che-postgres-pv.yaml
apiVersion: v1
kind: PersistentVolume
metadata:
  name: postgres-pv-volume
  labels:
    type: local
spec:
  storageClassName: postgres-storage
  capacity:
    storage: 1Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: "/data/che/postgres"

Define the persistent volume for a Che workspace:

# che-workspace-pv.yaml
apiVersion: v1
kind: PersistentVolume
metadata:
  name: workspace-pv-volume
  labels:
    type: local
spec:
  storageClassName: workspace-storage
  capacity:
    storage: 10Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: "/data/che/workspace"

Bind the two persistent volumes:

$ kubectl apply -f che-workspace-pv.yaml -f che-postgres-pv.yaml

You must provide valid file permissions for volumes. You can do it using storage class configuration or manually. To manually define permissions, define storageClass#mountOptions uid and gid. PostgreSQL volume requires uid=26 and gid=26.