mirror of
https://github.com/kubernetes-sigs/descheduler.git
synced 2026-01-26 05:14:13 +01:00
Merge pull request #208 from KohlsTechnology/install-docs
Streamline Deployment Docs For End Users
This commit is contained in:
Kubernetes Prow Robot
112
README.md
112
README.md
@@ -47,120 +47,40 @@ For more information about available options run:
|
||||
$ ./_output/bin/descheduler --help
|
||||
```
|
||||
|
||||
## Running Descheduler as a Job Inside of a Pod
|
||||
## Running Descheduler as a Job or CronJob
|
||||
|
||||
Descheduler can be run as a job inside of a pod. It has the advantage of
|
||||
The descheduler can be run as a job or cronjob inside of a pod. It has the advantage of
|
||||
being able to be run multiple times without needing user intervention.
|
||||
Descheduler pod is run as a critical pod to avoid being evicted by itself,
|
||||
or by kubelet due to an eviction event. Since critical pods are created in
|
||||
`kube-system` namespace, descheduler job and its pod will also be created
|
||||
The descheduler pod is run as a critical pod to avoid being evicted by itself,
|
||||
or by the kubelet due to an eviction event. Since critical pods are created in the
|
||||
`kube-system` namespace, the descheduler job and its pod will also be created
|
||||
in `kube-system` namespace.
|
||||
|
||||
### Create a container image
|
||||
### Setup RBAC
|
||||
|
||||
First we create a simple Docker image utilizing the Dockerfile found in the root directory:
|
||||
To give necessary permissions for the descheduler to work in a pod.
|
||||
|
||||
```
|
||||
$ make dev-image
|
||||
$ kubectl create -f kubernetes/rbac.yaml
|
||||
```
|
||||
|
||||
This creates an image based off the binary we've built before. To build both the
|
||||
binary and image in one step you can run the following command:
|
||||
|
||||
```
|
||||
$ make image
|
||||
```
|
||||
|
||||
This eliminates the need to have Go installed locally and builds the binary
|
||||
within it's own container.
|
||||
|
||||
### Create a cluster role
|
||||
|
||||
To give necessary permissions for the descheduler to work in a pod, create a cluster role:
|
||||
|
||||
```
|
||||
$ cat << EOF| kubectl create -f -
|
||||
kind: ClusterRole
|
||||
apiVersion: rbac.authorization.k8s.io/v1beta1
|
||||
metadata:
|
||||
name: descheduler-cluster-role
|
||||
rules:
|
||||
- apiGroups: [""]
|
||||
resources: ["nodes"]
|
||||
verbs: ["get", "watch", "list"]
|
||||
- apiGroups: [""]
|
||||
resources: ["pods"]
|
||||
verbs: ["get", "watch", "list", "delete"]
|
||||
- apiGroups: [""]
|
||||
resources: ["pods/eviction"]
|
||||
verbs: ["create"]
|
||||
EOF
|
||||
```
|
||||
|
||||
### Create the service account which will be used to run the job:
|
||||
|
||||
```
|
||||
$ kubectl create sa descheduler-sa -n kube-system
|
||||
```
|
||||
|
||||
### Bind the cluster role to the service account:
|
||||
|
||||
```
|
||||
$ kubectl create clusterrolebinding descheduler-cluster-role-binding \
|
||||
--clusterrole=descheduler-cluster-role \
|
||||
--serviceaccount=kube-system:descheduler-sa
|
||||
```
|
||||
### Create a configmap to store descheduler policy
|
||||
|
||||
Descheduler policy is created as a ConfigMap in `kube-system` namespace
|
||||
so that it can be mounted as a volume inside pod.
|
||||
|
||||
```
|
||||
$ kubectl create configmap descheduler-policy-configmap \
|
||||
-n kube-system --from-file=<path-to-policy-dir/policy.yaml>
|
||||
```
|
||||
### Create the job specification (descheduler-job.yaml)
|
||||
|
||||
```
|
||||
apiVersion: batch/v1
|
||||
kind: Job
|
||||
metadata:
|
||||
name: descheduler-job
|
||||
namespace: kube-system
|
||||
spec:
|
||||
parallelism: 1
|
||||
completions: 1
|
||||
template:
|
||||
metadata:
|
||||
name: descheduler-pod
|
||||
spec:
|
||||
priorityClassName: system-cluster-critical
|
||||
containers:
|
||||
- name: descheduler
|
||||
image: descheduler
|
||||
volumeMounts:
|
||||
- mountPath: /policy-dir
|
||||
name: policy-volume
|
||||
command: ["/bin/descheduler", "--policy-config-file", "/policy-dir/policy.yaml", "-v", "1"]
|
||||
restartPolicy: "Never"
|
||||
serviceAccountName: descheduler-sa
|
||||
volumes:
|
||||
- name: policy-volume
|
||||
configMap:
|
||||
name: descheduler-policy-configmap
|
||||
$ kubectl create -f kubernetes/configmap.yaml
|
||||
```
|
||||
|
||||
Please note that the pod template is configured with critical pod annotation, and
|
||||
the policy `policy-file` is mounted as a volume from the config map.
|
||||
### Create a Job or CronJob
|
||||
|
||||
### Run the descheduler as a job in a pod:
|
||||
As a Job.
|
||||
```
|
||||
$ kubectl create -f descheduler-job.yaml
|
||||
$ kubectl create -f kubernetes/job.yaml
|
||||
```
|
||||
|
||||
### Examples
|
||||
|
||||
See [descheduler.yaml](examples/descheduler.yaml) and [descheduler-job.yaml](examples/descheduler-job.yaml) for a combined yaml file of the above steps.
|
||||
Or as a CronJob.
|
||||
```
|
||||
$ kubectl create -f kubernetes/cronjob.yaml
|
||||
```
|
||||
|
||||
## Policy and Strategies
|
||||
|
||||
|
||||
@@ -1,27 +0,0 @@
|
||||
---
|
||||
apiVersion: batch/v1
|
||||
kind: Job
|
||||
metadata:
|
||||
name: descheduler-job
|
||||
namespace: kube-system
|
||||
spec:
|
||||
parallelism: 1
|
||||
completions: 1
|
||||
template:
|
||||
metadata:
|
||||
name: descheduler-pod
|
||||
spec:
|
||||
priorityClassName: system-cluster-critical
|
||||
containers:
|
||||
- name: descheduler
|
||||
image: docker.io/aveshagarwal/descheduler:0.9.0
|
||||
volumeMounts:
|
||||
- mountPath: /policy-dir
|
||||
name: policy-volume
|
||||
command: ["/bin/descheduler", "--policy-config-file", "/policy-dir/policy.yaml", "-v", "1"]
|
||||
restartPolicy: "Never"
|
||||
serviceAccountName: descheduler-sa
|
||||
volumes:
|
||||
- name: policy-volume
|
||||
configMap:
|
||||
name: descheduler-policy-configmap
|
||||
@@ -1,61 +0,0 @@
|
||||
---
|
||||
kind: ClusterRole
|
||||
apiVersion: rbac.authorization.k8s.io/v1beta1
|
||||
metadata:
|
||||
name: descheduler-cluster-role
|
||||
rules:
|
||||
- apiGroups: [""]
|
||||
resources: ["nodes"]
|
||||
verbs: ["get", "watch", "list"]
|
||||
- apiGroups: [""]
|
||||
resources: ["pods"]
|
||||
verbs: ["get", "watch", "list", "delete"]
|
||||
- apiGroups: [""]
|
||||
resources: ["pods/eviction"]
|
||||
verbs: ["create"]
|
||||
---
|
||||
apiVersion: v1
|
||||
kind: ServiceAccount
|
||||
metadata:
|
||||
name: descheduler-sa
|
||||
namespace: kube-system
|
||||
---
|
||||
apiVersion: rbac.authorization.k8s.io/v1beta1
|
||||
kind: ClusterRoleBinding
|
||||
metadata:
|
||||
name: descheduler-user
|
||||
roleRef:
|
||||
apiGroup: rbac.authorization.k8s.io
|
||||
kind: ClusterRole
|
||||
name: descheduler-cluster-role
|
||||
subjects:
|
||||
- kind: ServiceAccount
|
||||
name: descheduler-sa
|
||||
namespace: kube-system
|
||||
---
|
||||
kind: ConfigMap
|
||||
apiVersion: v1
|
||||
metadata:
|
||||
name: descheduler-policy-configmap
|
||||
namespace: kube-system
|
||||
data:
|
||||
policy.yaml: |
|
||||
apiVersion: "descheduler/v1alpha1"
|
||||
kind: "DeschedulerPolicy"
|
||||
strategies:
|
||||
"RemoveDuplicates":
|
||||
enabled: true
|
||||
"RemovePodsViolatingInterPodAntiAffinity":
|
||||
enabled: true
|
||||
"LowNodeUtilization":
|
||||
enabled: true
|
||||
params:
|
||||
nodeResourceUtilizationThresholds:
|
||||
thresholds:
|
||||
"cpu" : 20
|
||||
"memory": 20
|
||||
"pods": 20
|
||||
targetThresholds:
|
||||
"cpu" : 50
|
||||
"memory": 50
|
||||
"pods": 50
|
||||
@@ -1,3 +1,4 @@
|
||||
---
|
||||
apiVersion: v1
|
||||
kind: ConfigMap
|
||||
metadata:
|
||||
|
||||
35
kubernetes/cronjob.yaml
Normal file
35
kubernetes/cronjob.yaml
Normal file
@@ -0,0 +1,35 @@
|
||||
---
|
||||
apiVersion: batch/v1beta1
|
||||
kind: CronJob
|
||||
metadata:
|
||||
name: descheduler-cronjob
|
||||
namespace: kube-system
|
||||
spec:
|
||||
schedule: "*/2 * * * *"
|
||||
concurrencyPolicy: "Forbid"
|
||||
jobTemplate:
|
||||
spec:
|
||||
template:
|
||||
metadata:
|
||||
name: descheduler-pod
|
||||
spec:
|
||||
priorityClassName: system-cluster-critical
|
||||
containers:
|
||||
- name: descheduler
|
||||
image: us.gcr.io/k8s-artifacts-prod/descheduler:v0.10.0
|
||||
volumeMounts:
|
||||
- mountPath: /policy-dir
|
||||
name: policy-volume
|
||||
command:
|
||||
- "/bin/descheduler"
|
||||
args:
|
||||
- "--policy-config-file"
|
||||
- "/policy-dir/policy.yaml"
|
||||
- "--v"
|
||||
- "3"
|
||||
restartPolicy: "Never"
|
||||
serviceAccountName: descheduler-sa
|
||||
volumes:
|
||||
- name: policy-volume
|
||||
configMap:
|
||||
name: descheduler-policy-configmap
|
||||
@@ -1,3 +1,4 @@
|
||||
---
|
||||
apiVersion: batch/v1
|
||||
kind: Job
|
||||
metadata:
|
||||
@@ -9,12 +10,11 @@ spec:
|
||||
template:
|
||||
metadata:
|
||||
name: descheduler-pod
|
||||
annotations:
|
||||
scheduler.alpha.kubernetes.io/critical-pod: ""
|
||||
spec:
|
||||
priorityClassName: system-cluster-critical
|
||||
containers:
|
||||
- name: descheduler
|
||||
image: descheduler:latest
|
||||
image: us.gcr.io/k8s-artifacts-prod/descheduler:v0.10.0
|
||||
volumeMounts:
|
||||
- mountPath: /policy-dir
|
||||
name: policy-volume
|
||||
|
||||
Reference in New Issue
Block a user