Project: Litmus (Observability and Analysis / Chaos Engineering)
File: ebs-loss-by-id.md

It causes chaos to disrupt state of ebs volume by detaching it from the node/ec2 instance for a certain chaos duration using volume id. In case of EBS persistent volumes, the volumes can get self-attached and experiment skips the re-attachment step. Tests deployment sanity (replica availability & uninterrupted service) and recovery workflows of the application pod. !!! tip "Scenario: Detach EBS Volume" ??? info "View the uses of the experiment" coming soon ??? info "Verify the prerequisites" Ensure that Kubernetes Version > 1.16 Ensure that the Litmus Chaos Operator is running by executing <code>kubectl get pods</code> in operator namespace (typically, <code>litmus</code>).If not, install from <a href="https://v1-docs.litmuschaos.io/docs/getstarted/#install-litmus">here</a> Ensure that the <code>ebs-loss-by-id</code> experiment resource is available in the cluster by executing <code>kubectl get chaosexperiments</code> in the desired namespace. If not, install from <a href="https://hub.litmuschaos.io/api/chaos/master?file=faults/aws/ebs-loss-by-id/fault.yaml">here</a> Ensure that you have sufficient AWS access to attach or detach an ebs volume for the instance. Ensure to create a Kubernetes secret having the AWS access configuration(key) in the `CHAOS_NAMESPACE`. A sample secret file looks like: ```yaml apiVersion: v1 kind: Secret metadata: name: cloud-secret type: Opaque stringData: cloud_config.yml: |- [default] awsaccesskey_id = XXXXXXXXXXXXXXXXXXX awssecretaccess_key = XXXXXXXXXXXXXXX ``` If you change the secret key name (from `cloudconfig.yml`) please also update the `AWSSHAREDCREDENTIALSFILE` ENV value on `experiment.yaml`with the same name. ??? info "View the default validations" EBS volume is attached to the instance. !!! tip "NOTE" If you are using this experiment as part of a litmus workflow scheduled constructed & executed from chaos-center, then you may be making use of the RBAC, which is pre installed in the cluster as part of the agent setup. ??? note "View the Minimal RBAC permissions" ```yaml apiVersion: v1 kind: ServiceAccount metadata: name: ebs-loss-by-id-sa namespace: default labels: name: ebs-loss-by-id-sa app.kubernetes.io/part-of: litmus apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRole metadata: name: ebs-loss-by-id-sa labels: name: ebs-loss-by-id-sa

litmus rules: apiGroups: [""] resources: ["pods"] verbs: ["create","delete","get","list","patch","update", "deletecollection"] apiGroups: [""] resources: ["events"] verbs: ["create","get","list","patch","update"] apiGroups: [""] resources: ["secrets","configmaps"] verbs: ["get","list",] apiGroups: [""] resources: ["pods/log"] verbs: ["get","list","watch"] apiGroups: [""] resources: ["pods/exec"] verbs: ["get","list","create"] apiGroups: ["batch"] resources: ["jobs"] verbs: ["create","list","get","delete","deletecollection"] apiGroups: ["litmuschaos.io"] resources: ["chaosengines","chaosexperiments","chaosresults"] verbs: ["create","list","get","patch","update","delete"] apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRoleBinding metadata: name: ebs-loss-by-id-sa labels: name: ebs-loss-by-id-sa app.kubernetes.io/part-of: litmus roleRef: apiGroup: rbac.authorization.k8s.io kind: ClusterRole name: ebs-loss-by-id-sa subjects: kind: ServiceAccount name: ebs-loss-by-id-sa namespace: default ``` Use this sample RBAC manifest to create a chaosServiceAccount in the desired (app) namespace. This example consists of the minimum necessary role permissions to execute the experiment. ??? info "check the experiment tunables" <h2>Mandatory Fields</h2> <table> <tr> <th> Variables </th> <th> Description </th> <th> Notes </th> </tr> <tr> <td> EBSVOLUMEID </td> <td> Comma separated list of volume IDs subjected to ebs detach chaos</td> <td> </td> </tr> <tr> <td> REGION </td> <td> The region name for the target volumes</td> <td> </td> </tr> </table> <h2>Optional Fields</h2> <table> <tr> <th> Variables </th> <th> Description </th> <th> Notes </th> </tr> <tr> <td> TOTALCHAOSDURATION </td> <td> The time duration for chaos insertion (sec) </td> <td> Defaults to 30s </td> </tr> <tr> <td> CHAOS_INTERVAL </td> <td> The time duration between the attachment and detachment of the volumes (sec) </td> <td> Defaults to 30s </td> </tr> <tr> <td> SEQUENCE </td> <td> It defines sequence of chaos execution for multiple volumes</td> <td> Default value: parallel. Supported: serial, parallel </td> </tr> <tr> <td> RAMP_TIME </td> <td> Period to wait before and after injection of chaos in sec </td> <td> </td> </tr> </table> Refer the and to tune the common tunables for all experiments and aws specific tunables. It contains comma separated list of volume IDs subjected to ebs detach chaos. It can be tuned via `EBSVOLUMEID` ENV. Use the following example to tune this: ```yaml apiVersion: litmuschaos.io/v1alpha1 kind: ChaosEngine metadata: name: engine-nginx spec: engineState: "active" annotationCheck: "false" chaosServiceAccount: ebs-loss-by-id-sa experiments: name: ebs-loss-by-id spec: components: env: name: EBSVOLUMEID value: 'ebs-vol-1' name: REGION value: '<region for EBSVOLUMEID>' name: TOTALCHAOSDURATION value: '60' ```