参考文档地址：https://edu.51cto.com/course/30254.html
1、Metrics-Server是什么?
Metrics-Server是集群核心监控数据的聚合器。通俗地说，它存储了集群中各节点的监控数据，并且提供了API以供分析和使用。 Metrics-Server在Kubernetes集群中表现为一个Deployment对象。不过准确地说，它是Deployment，Service，ClusterRole，ClusterRoleBinding，APIService，RoleBinding资源对象的综合体。
2、作用：
Metrics-Server的主要作用为为kube-scheduler，HorizontalPodAutoscaler等k8s核心组件，以及kubectl top命令和Dashboard等UI组件提供数据来源。 除此之外，也可以自定义Metrics-Server，添加一些其他的监控指标，比如说比较流行的k8s-prometheus-adapter。
3、部署
cat metrics-server.yml
apiVersion: v1
kind: ServiceAccount
metadata:
labels:
k8s-app: metrics-server
name: metrics-server
namespace: kube-system
---
apiVersion: /v1
kind: ClusterRole
metadata:
labels:
k8s-app: metrics-server
/aggregate-to-admin: undefinedtrueundefined
/aggregate-to-edit: undefinedtrueundefined
/aggregate-to-view: undefinedtrueundefined
name: system:aggregated-metrics-reader
rules:
- apiGroups:
-
resources:
- pods
- nodes
verbs:
- get
- list
- watch
---
apiVersion: /v1
kind: ClusterRole
metadata:
labels:
k8s-app: metrics-server
name: system:metrics-server
rules:
- apiGroups:
- undefinedundefined
resources:
- pods
- nodes
- nodes/stats
- namespaces
- configmaps
verbs:
- get
- list
- watch
---
apiVersion: /v1
kind: RoleBinding
metadata:
labels:
k8s-app: metrics-server
name: metrics-server-auth-reader
namespace: kube-system
roleRef:
apiGroup:
kind: Role
name: extension-apiserver-authentication-reader
subjects:
- kind: ServiceAccount
name: metrics-server
namespace: kube-system
---
apiVersion: /v1
kind: ClusterRoleBinding
metadata:
labels:
k8s-app: metrics-server
name: metrics-server:system:auth-delegator
roleRef:
apiGroup:
kind: ClusterRole
name: system:auth-delegator
subjects:
- kind: ServiceAccount
name: metrics-server
namespace: kube-system
---
apiVersion: /v1
kind: ClusterRoleBinding
metadata:
labels:
k8s-app: metrics-server
name: system:metrics-server
roleRef:
apiGroup:
kind: ClusterRole
name: system:metrics-server
subjects:
- kind: ServiceAccount
name: metrics-server
namespace: kube-system
---
apiVersion: v1
kind: Service
metadata:
labels:
k8s-app: metrics-server
name: metrics-server
namespace: kube-system
spec:
ports:
- name: https
port: 443
protocol: TCP
targetPort: https
selector:
k8s-app: metrics-server
---
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
k8s-app: metrics-server
name: metrics-server
namespace: kube-system
spec:
selector:
matchLabels:
k8s-app: metrics-server
strategy:
rollingUpdate:
maxUnavailable: 0
template:
metadata:
labels:
k8s-app: metrics-server
spec:
containers:
- args:
- --cert-dir=/tmp
- --secure-port=4443
- --metric-resolution=30s
- --kubelet-insecure-tls
- --kubelet-preferred-address-types=InternalIP
- --kubelet-use-node-status-port
#image: /metrics-server/metrics-server:v0.4.1
image: bitnami/metrics-server:0.4.1
imagePullPolicy: IfNotPresent
livenessProbe:
failureThreshold: 3
httpGet:
path: /livez
port: https
scheme: HTTPS
periodSeconds: 10
name: metrics-server
ports:
- containerPort: 4443
name: https
protocol: TCP
readinessProbe:
failureThreshold: 3
httpGet:
path: /readyz
port: https
scheme: HTTPS
periodSeconds: 10
securityContext:
readOnlyRootFilesystem: true
runAsNonRoot: true
runAsUser: 1000
volumeMounts:
- mountPath: /tmp
name: tmp-dir
nodeSelector:
kubernetes.io/os: linux
priorityClassName: system-cluster-critical
serviceAccountName: metrics-server
volumes:
- emptyDir: {}
name: tmp-dir
---
apiVersion: /v1
kind: APIService
metadata:
labels:
k8s-app: metrics-server
name: v1beta1.
spec:
group:
groupPriorityMinimum: 100
insecureSkipTLSVerify: true
service:
name: metrics-server
namespace: kube-system
version: v1beta1
versionPriority: 100
镜像这块大家需要注意下，很多文章里边说用“/metrics-server/metrics-server”这个镜像，但是由于所众周知的原因，很多人的网络是拉取不到这个镜像的，所以得换成其他能拉取到的镜像地址，比如“ bitnami/metrics-server”，如下是我的镜像相关配置
#image: /metrics-server/metrics-server:v0.4.1
image: bitnami/metrics-server:0.4.1
可以用“docker search metrics-server:v0.4.1”查看哪些镜像能拉取
#docker search metrics-server:v0.4.1
NAME DESCRIPTION STARS OFFICIAL AUTOMATED
phperall/metrics-server /metrics-server/metrics-server:v0.… 0
wdhcn/metric-server From /metrics-server/metrics-serve… 0
#docker pull phperall/metrics-server:v0.4.1
v0.4.1: Pulling from phperall/metrics-server
e59bd8947ac7: Pull complete
cdbcff7dade2: Pull complete
Digest: sha256:2009bb9ca86e8bdfc035a37561cf062f3e051c35823a5481fbd13533ce402fac
Status: Downloaded newer image for phperall/metrics-server:v0.4.1
/phperall/metrics-server:v0.4.1
部署并查看
#kubectl apply -f metrics-server.yml
#kubectl get pods -A |grep metrics-server
kube-system metrics-server-7744c64748-r5lw4 1/1 Running 0 61m
4、使用
举一个简单的使用例子：查看node、pod资源使用情况
#kubectl top nodes
NAME CPU(cores) CPU% MEMORY(bytes) MEMORY%
k8s-master01 230m 5% 1496Mi 40%
k8s-node01 101m 2% 2416Mi 65%
#kubectl top pods
NAME CPU(cores) MEMORY(bytes)
my-nginx-8d545c96d-mwwr2 0m 3Mi
my-nginx-8d545c96d-srsdq 0m 3Mi
my-nginx-8d545c96d-v2p7h 0m 3Mi
