Kubernetes locations installation
Run a Control Plane on Kubernetes, to set up your Private Locations and run load generators in your own Kubernetes network.
Introduction
A control plane, installed on a kubernetes cluster with the needed roles will be able to deploy kubernetes private locations.
To better understand what roles are needed, here’s a quick overview of the mechanisms involved when deploying a private location on Kubernetes.
First, the control plane regularly polls the Gatling Enterprise API, and it is notified to deploy a number of instances in a given Kubernetes location.
Then, it creates a config map for each namespace of each Kubernetes location requested for this run. The config map includes the load generator’s start script, so these scripts don’t need to be embedded in the Docker images used for the load generators.
Finally, the control plane initiates a batch job, with the number of instances configured for the simulation run, and mounts the appropriate config map on each pod.
Roles
For each namespace configured for a private location, the control plane needs the following roles:
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
name: control-plane-role
namespace: <namespace>
rules:
- apiGroups: [""]
resources: ["configmaps"]
verbs: ["create", "get", "patch", "update", "delete"]
- apiGroups: ["batch"]
resources: ["jobs"]
verbs: ["create", "get", "deletecollection"]
- apiGroups: [""]
resources: ["pods"]
verbs: ["list"]
- apiGroups: [""]
resources: ["pods/log"]
verbs: ["get"]
Example
The control plane requires a configuration under /app/conf/control-plane.conf, see control plane configuration.
To accomplish this, create a config map called control-plane-config that includes a file named control-plane.conf.
This file is be mounted into the container using the following command:
kubectl create configmap control-plane-config \
--from-file=control-plane.conf
If your configuration references additional files, you can include them as well:
kubectl create configmap control-plane-config \
--from-file=control-plane.conf \
--from-file=job.json
apiVersion: v1
kind: ServiceAccount
metadata:
name: control-plane-service-account
namespace: gatling
---
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
name: control-plane-role
namespace: gatling
rules:
- apiGroups: [""]
resources: ["configmaps"]
verbs: ["create", "get", "patch", "update", "delete"]
- apiGroups: ["batch"]
resources: ["jobs"]
verbs: ["create", "get", "deletecollection"]
- apiGroups: [""]
resources: ["pods"]
verbs: ["list"]
- apiGroups: [""]
resources: ["pods/log"]
verbs: ["get"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: control-plane-role-binding
namespace: gatling
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: control-plane-role
subjects:
- kind: ServiceAccount
name: control-plane-service-account
namespace: gatling
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: control-plane
namespace: gatling
spec:
replicas: 1
selector:
matchLabels:
name: control-plane-template
template:
metadata:
labels:
name: control-plane-template
spec:
serviceAccountName: control-plane-service-account
containers:
- name: control-plane
image: gatlingcorp/control-plane:latest
volumeMounts:
- mountPath: /app/conf/
name: control-plane-conf-volume
volumes:
- name: control-plane-conf-volume
configMap:
name: control-plane-config
Troubleshooting
Run timeout while control plane logged a successful deployment
The control plane initiated a request to the Kubernetes API to deploy load generators using Batch Job. Although the Kubernetes API responded with an OK status, the actual deployment of the underlying job may have failed.
First, inspect existing jobs and pods:
kubectl get jobs --namespace=gatling
kubectl get pods --namespace=gatling
If no resources are found, examine events related to jobs:
kubectl get events --namespace=gatling --field-selector involvedObject.kind=Job
Deploy resources using Helm
Gatling provides Helm chart to set up Kubernetes resources for Private Locations, visit our dedicated GitHub repository