slow-csi

This CSI (Container Storage Interface) plugin does nothing but time.Sleep(). It simulates pending operations with configurable delays, useful for debugging, triggering timeouts, etc.

Delayable RPCs:

• CreateVolume
• DeleteVolume
• NodeStageVolume
• NodeUnstageVolume
• NodePublishVolume
• NodeUnpublishVolume

Building

slow-csi plugin can be compiled in a form of a binary file or in a form of a Docker image. When compiled as a binary file, the result is stored in _output/ directory with the name slowplugin. When compiled as an image, it's stored in the local Docker image store.

Building binary:

$ make plugin

Building Docker image:

$ make image

Configuration

Available command line arguments:

Option	Default value	Description
--endpoint	unix://tmp/csi.sock	CSI endpoint, must be a UNIX socket
--drivername	csi-slowplugin	name of the driver (Kubernetes: provisioner field in StorageClass must correspond to this value)
--nodeid	empty	This node's ID
--defaultdelay	empty	Default delay for all delayable RPCs. Defaults to 0
--delay	empty	Per-RPC delay configuration in format RPC1=DELAY,RPC2=DELAY,...

Delay format

All delays are in seconds and may be in one of three formats:

• n: simple number
• a..b: random delay in an interval [a, b), b must be greater than a
• inf: infinite delay, such RPC will never finish

Example: --delay=CreateVolume=10..20,DeleteVolume=5,NodeUnstageVolume=inf

Deployment with Kubernetes

Requires Kubernetes 1.11

Your Kubernetes cluster must allow privileged pods (i.e. --allow-privileged flag must be set to true for both the API server and the kubelet). Moreover, as stated in the mount propagation docs, the Docker daemon of the cluster nodes must allow shared mounts.

YAML manifests are located in deploy/kubernetes.

Deploy RBACs for sidecar containers and node plugins:

$ kubectl create -f csi-attacher-rbac.yaml
$ kubectl create -f csi-provisioner-rbac.yaml
$ kubectl create -f csi-nodeplugin-rbac.yaml

Those manifests deploy service accounts, cluster roles and cluster role bindings.

Deploy CSI sidecar containers:

$ kubectl create -f csi-slowplugin-attacher.yaml
$ kubectl create -f csi-slowplugin-provisioner.yaml

Deploys stateful sets for external-attacher and external-provisioner sidecar containers for slow-csi.

Deploy slow-csi driver:

$ kubectl create -f csi-slowplugin.yaml

Deploys a daemon set with two containers: CSI driver-registrar and the slow-csi driver. Here you can configure the delays.

Once the driver is successfully deployed, you can deploy the storage class, PVC and a deployment, no changes required. YAML manifests for those are located in run/:

$ kubectl create -f storageclass.yaml
$ kubectl create -f pvc.yaml
$ kubectl create -f deployment.yaml