service-disruption-scenarios.md

Namespace/Service Disruption Scenarios

This scenario deletes main objects within a namespace in your Kubernetes/OpenShift cluster. More information can be found here.

Run

If enabling Cerberus to monitor the cluster and pass/fail the scenario post chaos, refer docs. Make sure to start it before injecting the chaos and set CERBERUS_ENABLED environment variable for the chaos injection container to autoconnect.

$ podman run --name=<container_name> --net=host --env-host=true -v <path-to-kube-config>:/home/krkn/.kube/config:Z -d quay.io/krkn-chaos/krkn-hub:service-disruption-scenarios
# podman logs -f <container_name or container_id> # Streams Kraken logs
$ podman inspect <container-name or container-id> --format "{{.State.ExitCode}}" # Outputs exit code which can considered as pass/fail for the scenario

$ docker run $(./get_docker_params.sh) --name=<container_name> --net=host -v <path-to-kube-config>:/home/krkn/.kube/config:Z -d quay.io/krkn-chaos/krkn-hub:service-disruption-scenarios
OR 
$ docker run -e <VARIABLE>=<value> --net=host -v <path-to-kube-config>:/home/krkn/.kube/config:Z -d quay.io/krkn-chaos/krkn-hub:service-disruption-scenarios

$ docker logs -f <container_name or container_id> # Streams Kraken logs
$ docker inspect <container-name or container-id> --format "{{.State.ExitCode}}" # Outputs exit code which can considered as pass/fail for the scenario

TIP: Because the container runs with a non-root user, ensure the kube config is globally readable before mounting it in the container. You can achieve this with the following commands: kubectl config view --flatten > ~/kubeconfig && chmod 444 ~/kubeconfig && docker run $(./get_docker_params.sh) --name=<container_name> --net=host -v ~kubeconfig:/home/krkn/.kube/config:Z -d quay.io/krkn-chaos/krkn-hub:<scenario>

Demo

See here for a demo of this scenario

Supported parameters

The following environment variables can be set on the host running the container to tweak the scenario/faults being injected:

ex.) export <parameter_name>=<value>

See list of variables that apply to all scenarios here that can be used/set in addition to these scenario specific variables

Parameter	Description	Default
LABEL_SELECTOR	Label of the namespace to target. Set this parameter only if NAMESPACE is not set	""
NAMESPACE	Name of the namespace you want to target. Set this parameter only if LABEL_SELECTOR is not set	"openshift-etcd"
SLEEP	Number of seconds to wait before polling to see if namespace exists again	15
DELETE_COUNT	Number of namespaces to kill in each run, based on matching namespace and label specified	1
RUNS	Number of runs to execute the action	1

NOTE In case of using custom metrics profile or alerts profile when CAPTURE_METRICS or ENABLE_ALERTS is enabled, mount the metrics profile from the host on which the container is run using podman/docker under /home/krkn/kraken/config/metrics-aggregated.yaml and /home/krkn/kraken/config/alerts. For example:

$ podman run --name=<container_name> --net=host --env-host=true -v <path-to-custom-metrics-profile>:/home/krkn/kraken/config/metrics-aggregated.yaml -v <path-to-custom-alerts-profile>:/home/krkn/kraken/config/alerts -v <path-to-kube-config>:/home/krkn/.kube/config:Z -d quay.io/krkn-chaos/krkn-hub:service-disruption-scenarios