Resource Quotas & Limits in Kubernetes

Делаю: 09.04.2019

По материалам из видео индуса:

https://www.youtube.com/watch?v=4C-0idGOi2A&list=PL34sAs7_26wNBRWM6BDhnonoA5FMERax0&index=17

Подготовили кластер и окружение как здесь.

Resource Quotas

$ kubectl create namespace quota-demo-ns

$ kubectl create -f https://bitbucket.org/sysadm-ru/kubernetes/raw/faf2f86a2c1bb82053c5aba9ea7c96463e4e61b0/yamls/7-quota-count.yaml

$ kubectl -n quota-demo-ns describe quota quota-demo1
Name:       quota-demo1
Namespace:  quota-demo-ns
Resource    Used  Hard
--------    ----  ----
configmaps  0     1
pods        0     2

$ kubectl -n quota-demo-ns create configmap cm1 --from-literal=name=venkatn

$ kubectl -n quota-demo-ns describe quota quota-demo1
Name:       quota-demo1
Namespace:  quota-demo-ns
Resource    Used  Hard
--------    ----  ----
configmaps  1     1
pods        0     2

// Ошибка!!!
$ kubectl -n quota-demo-ns create configmap cm2 --from-literal=name=venkatn

$ kubectl -n quota-demo-ns delete cm cm1

$ kubectl -n quota-demo-ns run nginx --image=nginx --replicas=1

$ kubectl -n quota-demo-ns describe quota quota-demo1
Name:       quota-demo1
Namespace:  quota-demo-ns
Resource    Used  Hard
--------    ----  ----
configmaps  0     1
pods        1     2


$ kubectl -n quota-demo-ns scale deploy nginx --replicas=3

$ kubectl -n quota-demo-ns get all
NAME                         READY   STATUS    RESTARTS   AGE
pod/nginx-7db9fccd9b-g7vgr   1/1     Running   0          2m50s
pod/nginx-7db9fccd9b-ttzfd   1/1     Running   0          60s

NAME                    READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/nginx   2/3     2            2           2m50s

NAME                               DESIRED   CURRENT   READY   AGE
replicaset.apps/nginx-7db9fccd9b   3         2         2       2m50s

$ kubectl -n quota-demo-ns delete deploy nginx

$ kubectl -n quota-demo-ns delete quota quota-demo1

Resource Limits (CPU, Memory etc.)

$ kubectl create -f https://bitbucket.org/sysadm-ru/kubernetes/raw/faf2f86a2c1bb82053c5aba9ea7c96463e4e61b0/yamls/7-quota-mem.yaml

$ kubectl -n quota-demo-ns describe quota quota-demo-mem
Name:          quota-demo-mem
Namespace:     quota-demo-ns
Resource       Used  Hard
--------       ----  ----
limits.memory  0     500Mi

// Ошибка должны быть определены лимиты памяти
$ kubectl create -f https://bitbucket.org/sysadm-ru/kubernetes/raw/faf2f86a2c1bb82053c5aba9ea7c96463e4e61b0/yamls/7-pod-quota-mem.yaml

$ cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Pod
metadata:
  name: nginx
  namespace: quota-demo-ns
spec:
  containers:
  - image: nginx
    name: nginx
    resources:
      limits:
        memory: "100Mi"
EOF

$ kubectl -n quota-demo-ns describe quota quota-demo-mem
Name:          quota-demo-mem
Namespace:     quota-demo-ns
Resource       Used   Hard
--------       ----   ----
limits.memory  100Mi  500Mi

$ kubectl delete -f https://bitbucket.org/sysadm-ru/kubernetes/raw/faf2f86a2c1bb82053c5aba9ea7c96463e4e61b0/yamls/7-pod-quota-mem.yaml

$ kubectl -n quota-demo-ns delete quota quota-demo-mem

Limit range

$ kubectl create -f https://bitbucket.org/sysadm-ru/kubernetes/raw/faf2f86a2c1bb82053c5aba9ea7c96463e4e61b0/yamls/7-quota-limitrange.yaml


$ kubectl -n quota-demo-ns describe limitrange mem-limitrange
Name:       mem-limitrange
Namespace:  quota-demo-ns
Type        Resource  Min  Max  Default Request  Default Limit  Max Limit/Request Ratio
----        --------  ---  ---  ---------------  -------------  -----------------------
Container   memory    -    -    50Mi             300Mi          -

$ kubectl create -f https://bitbucket.org/sysadm-ru/kubernetes/raw/faf2f86a2c1bb82053c5aba9ea7c96463e4e61b0/yamls/7-pod-quota-mem.yaml

$ kubectl delete -f https://bitbucket.org/sysadm-ru/kubernetes/raw/faf2f86a2c1bb82053c5aba9ea7c96463e4e61b0/yamls/7-pod-quota-mem.yaml

$ kubectl create -f https://bitbucket.org/sysadm-ru/kubernetes/raw/faf2f86a2c1bb82053c5aba9ea7c96463e4e61b0/yamls/7-quota-limitrange.yaml

$ cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: ResourceQuota
metadata:
  name: quota-demo-mem
  namespace: quota-demo-ns
spec:
  hard:
    limits.memory: "500Mi"
    requests.memory: "100Mi"
EOF

Добавили строку: requests.memory: “100Mi”

$ kubectl -n quota-demo-ns describe quota quota-demo-mem
Name:            quota-demo-mem
Namespace:       quota-demo-ns
Resource         Used  Hard
--------         ----  ----
limits.memory    0     500Mi
requests.memory  0     100Mi

$ cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Pod
metadata:
  name: nginx
  namespace: quota-demo-ns
spec:
  containers:
  - image: nginx
    name: nginx
    resources:
      limits:
        memory: "200Mi"
EOF

Ошибка, тк просит больше 100.

$ cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Pod
metadata:
  name: nginx
  namespace: quota-demo-ns
spec:
  containers:
  - image: nginx
    name: nginx
    resources:
      limits:
        memory: "200Mi"
      requests:
        memory: "50Mi"
EOF