Prometheus
Prometheus介绍
Prometheus是一套由SoundCloud公司开发的开源的监控、报警、时间序列数据库项目,它采用定期拉取接口的方式来采集需要统计的指标
Prometheus基本原理是通过HTTP协议周期性抓取被监控组件的状态,这样做的好处是任意组件只要提供HTTP接口就可以接入监控系统,不需要任何SDK或者其他的集成过程。这样做非常适合虚拟化环境比如VM或者Docker。
Prometheus特点
- 多维数据模型(时序列数据由metric名和一组key/value组成)
- 在多维度上灵活的查询语言(PromQl)
- 不依赖分布式存储,单主节点工作
- 通过基于HTTP的pull方式采集时序数据
- 可以通过中间网关进行时序列数据推送(pushing)
- 目标服务器可以通过发现服务或者静态配置实现
- 多种可视化和仪表盘支持
部署
前提:已部署好K8S集群(kube-dns或者coredns)
原理
在k8s集群中使用node-exporter、prometheus、grafana对集群进行监控
- node-exporter组件负责收集节点上的metrics监控数据,并将数据推送给prometheus
- prometheus负责存储这些数据
- grafana将这些数据通过网页以图形的形式展现给用户
环境介绍
主机名 | ip | 主机配置 | 备注 |
---|---|---|---|
master01 | 192.168.213.181 | 4U4G | control plane |
node01 | 192.168.213.192 | 2U2G | node |
node02 | 192.168.213.192 | 2U2G | node |
部署node-exporter组件
采用daemonset方式部署node-exporter组件
[root@master01 ~]# cat node-exporter.yaml
apiVersion: extensions/v1beta1
kind: DaemonSet
metadata:
name: node-exporter
namespace: kube-system
labels:
k8s-app: node-exporter
spec:
template:
metadata:
labels:
k8s-app: node-exporter
spec:
containers:
- image: prom/node-exporter
name: node-exporter
ports:
- containerPort: 9100
protocol: TCP
name: http
---
apiVersion: v1
kind: Service
metadata:
labels:
k8s-app: node-exporter
name: node-exporter
namespace: kube-system
spec:
ports:
- name: http
port: 9100
nodePort: 31672
protocol: TCP
type: NodePort
selector:
k8s-app: node-exporter
部署prometheus组件
rbac文件
[root@master01 ~]# cat rbac-setup.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: prometheus
rules:
- apiGroups: [""]
resources:
- nodes
- nodes/proxy
- services
- endpoints
- pods
verbs: ["get", "list", "watch"]
- apiGroups:
- extensions
resources:
- ingresses
verbs: ["get", "list", "watch"]
- nonResourceURLs: ["/metrics"]
verbs: ["get"]
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: prometheus
namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: prometheus
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: prometheus
subjects:
- kind: ServiceAccount
name: prometheus
namespace: kube-system
以configmap的形式管理prometheus组件的配置文件
[root@master01 ~]# cat configmap.yaml
apiVersion: v1
kind: ConfigMap
metadata:
name: prometheus-config
namespace: kube-system
data:
prometheus.yml: |
global:
scrape_interval: 15s
evaluation_interval: 15s
scrape_configs:
- job_name: ‘kubernetes-apiservers‘
kubernetes_sd_configs:
- role: endpoints
scheme: https
tls_config:
ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
relabel_configs:
- source_labels: [__meta_kubernetes_namespace, __meta_kubernetes_service_name, __meta_kubernetes_endpoint_port_name]
action: keep
regex: default;kubernetes;https
- job_name: ‘kubernetes-nodes‘
kubernetes_sd_configs:
- role: node
scheme: https
tls_config:
ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
relabel_configs:
- action: labelmap
regex: __meta_kubernetes_node_label_(.+)
- target_label: __address__
replacement: kubernetes.default.svc:443
- source_labels: [__meta_kubernetes_node_name]
regex: (.+)
target_label: __metrics_path__
replacement: /api/v1/nodes/${1}/proxy/metrics
- job_name: ‘kubernetes-cadvisor‘
kubernetes_sd_configs:
- role: node
scheme: https
tls_config:
ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
relabel_configs:
- action: labelmap
regex: __meta_kubernetes_node_label_(.+)
- target_label: __address__
replacement: kubernetes.default.svc:443
- source_labels: [__meta_kubernetes_node_name]
regex: (.+)
target_label: __metrics_path__
replacement: /api/v1/nodes/${1}/proxy/metrics/cadvisor
- job_name: ‘kubernetes-service-endpoints‘
kubernetes_sd_configs:
- role: endpoints
relabel_configs:
- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scrape]
action: keep
regex: true
- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scheme]
action: replace
target_label: __scheme__
regex: (https?)
- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_path]
action: replace
target_label: __metrics_path__
regex: (.+)
- source_labels: [__address__, __meta_kubernetes_service_annotation_prometheus_io_port]
action: replace
target_label: __address__
regex: ([^:]+)(?::\d+)?;(\d+)
replacement: $1:$2
- action: labelmap
regex: __meta_kubernetes_service_label_(.+)
- source_labels: [__meta_kubernetes_namespace]
action: replace
target_label: kubernetes_namespace
- source_labels: [__meta_kubernetes_service_name]
action: replace
target_label: kubernetes_name
- job_name: ‘kubernetes-services‘
kubernetes_sd_configs:
- role: service
metrics_path: /probe
params:
module: [http_2xx]
relabel_configs:
- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_probe]
action: keep
regex: true
- source_labels: [__address__]
target_label: __param_target
- target_label: __address__
replacement: blackbox-exporter.example.com:9115
- source_labels: [__param_target]
target_label: instance
- action: labelmap
regex: __meta_kubernetes_service_label_(.+)
- source_labels: [__meta_kubernetes_namespace]
target_label: kubernetes_namespace
- source_labels: [__meta_kubernetes_service_name]
target_label: kubernetes_name
- job_name: ‘kubernetes-ingresses‘
kubernetes_sd_configs:
- role: ingress
relabel_configs:
- source_labels: [__meta_kubernetes_ingress_annotation_prometheus_io_probe]
action: keep
regex: true
- source_labels: [__meta_kubernetes_ingress_scheme,__address__,__meta_kubernetes_ingress_path]
regex: (.+);(.+);(.+)
replacement: ${1}://${2}${3}
target_label: __param_target
- target_label: __address__
replacement: blackbox-exporter.example.com:9115
- source_labels: [__param_target]
target_label: instance
- action: labelmap
regex: __meta_kubernetes_ingress_label_(.+)
- source_labels: [__meta_kubernetes_namespace]
target_label: kubernetes_namespace
- source_labels: [__meta_kubernetes_ingress_name]
target_label: kubernetes_name
- job_name: ‘kubernetes-pods‘
kubernetes_sd_configs:
- role: pod
relabel_configs:
- source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_scrape]
action: keep
regex: true
- source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_path]
action: replace
target_label: __metrics_path__
regex: (.+)
- source_labels: [__address__, __meta_kubernetes_pod_annotation_prometheus_io_port]
action: replace
regex: ([^:]+)(?::\d+)?;(\d+)
replacement: $1:$2
target_label: __address__
- action: labelmap
regex: __meta_kubernetes_pod_label_(.+)
- source_labels: [__meta_kubernetes_namespace]
action: replace
target_label: kubernetes_namespace
- source_labels: [__meta_kubernetes_pod_name]
action: replace
target_label: kubernetes_pod_name
Prometheus deployment 文件
[root@master01 ~]# cat prometheus.yaml
apiVersion: apps/v1beta2
kind: Deployment
metadata:
labels:
name: prometheus-deployment
name: prometheus
namespace: kube-system
spec:
replicas: 1
selector:
matchLabels:
app: prometheus
template:
metadata:
labels:
app: prometheus
spec:
containers:
- image: prom/prometheus:v2.0.0
name: prometheus
command:
- "/bin/prometheus"
args:
- "--config.file=/etc/prometheus/prometheus.yml"
- "--storage.tsdb.path=/prometheus"
- "--storage.tsdb.retention=24h"
ports:
- containerPort: 9090
protocol: TCP
volumeMounts:
- mountPath: "/prometheus"
name: data
- mountPath: "/etc/prometheus"
name: config-volume
resources:
requests:
cpu: 100m
memory: 100Mi
limits:
cpu: 500m
memory: 2500Mi
serviceAccountName: prometheus
volumes:
- name: data
emptyDir: {}
- name: config-volume
configMap:
name: prometheus-config
---
kind: Service
apiVersion: v1
metadata:
labels:
app: prometheus
name: prometheus
namespace: kube-system
spec:
type: NodePort
ports:
- port: 9090
targetPort: 9090
nodePort: 30003
selector:
app: prometheus
通过yaml文件创建相应的对象
kubectl create -f node-exporter.yaml
kubectl create -f rbac-setup.yaml
kubectl create -f configmap.yaml
kubectl create -f promethues.yaml
查看相关pod和service
结果验证
Node-exporter对应的nodeport端口为31672,通过访问http://192.168.213.181:31672/metrics可以看到对应的metrics
prometheus对应的nodeport端口为30003,通过访问http://192.168.213.181:30003/targets可以看到prometheus已经成功连接上了k8s的apiserver
在prometheus的WEB界面上提供了基本的查询,可以使用如下查询条件查询K8S集群中每个POD的CPU使用情况sum by (pod_name)( rate(container_cpu_usage_seconds_total{image!="", pod_name!=""}[1m] ) )
上述的查询有出现数据,说明node-exporter往prometheus中写入数据正常
部署grafana组件
部署grafana组件,实现更友好的WEBUI展示数据
#grafana deployment配置文件
[root@master01 ~]# cat grafana.yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: grafana-core
namespace: kube-system
labels:
app: grafana
component: core
spec:
replicas: 1
template:
metadata:
labels:
app: grafana
component: core
spec:
containers:
- image: grafana/grafana:5.0.0
name: grafana-core
imagePullPolicy: IfNotPresent
resources:
limits:
cpu: 100m
memory: 100Mi
requests:
cpu: 100m
memory: 100Mi
env:
- name: GF_AUTH_BASIC_ENABLED
value: "true"
- name: GF_AUTH_ANONYMOUS_ENABLED
value: "false"
readinessProbe:
httpGet:
path: /login
port: 3000
volumeMounts:
- name: grafana-persistent-storage
mountPath: /var
volumes:
- name: grafana-persistent-storage
emptyDir: {}
---
apiVersion: v1
kind: Service
metadata:
name: grafana
namespace: kube-system
labels:
app: grafana
component: core
spec:
type: NodePort
ports:
- port: 3000
nodePort: 31000
selector:
app: grafana
[root@master01 ~]# kubectl create -f grafana.yaml
查看grafana pod和service
[root@master01 ~]# kubectl get pod -n kube-system
[root@master01 ~]# kubectl get svc -n kube-system
可以看到grafana nodeport端口为31000,可使用nodeip+nodeport的方式访问grafana http://192.168.213.181:31000
配置数据库源为prometheus,导入面板(可以直接输入模板编号315在线导入,或者下载好对应的json模板文件本地导入)
加载模板后,选择prometheus数据库实例
查看监控页面