Kubernetes K8S之kube-prometheus概述与部署

Kubernetes K8S之kube-prometheus概述与部署

主机配置规划

服务器名称(hostname)	系统版本	配置	内网IP	外网IP(模拟)
k8s-master	CentOS7.7	2C/4G/20G	172.16.1.110	10.0.0.110
k8s-node01	CentOS7.7	2C/4G/20G	172.16.1.111	10.0.0.111
k8s-node02	CentOS7.7	2C/4G/20G	172.16.1.112	10.0.0.112

prometheus概述

Prometheus是一个开源的系统监控和警报工具包，自2012成立以来，许多公司和组织采用了Prometheus。它现在是一个独立的开源项目，并独立于任何公司维护。在2016年，Prometheus加入云计算基金会作为Kubernetes之后的第二托管项目。

Prometheus性能也足够支撑上万台规模的集群。

Prometheus的关键特性

• 多维度数据模型
• 灵活的查询语言
• 不依赖于分布式存储；单服务器节点是自治的
• 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
• 通过服务发现或者静态配置来发现目标服务对象
• 支持多种多样的图表和界面展示，比如Grafana等

架构图

基本原理

Prometheus的基本原理是通过HTTP协议周期性抓取被监控组件的状态，任意组件只要提供对应的HTTP接口就可以接入监控。不需要任何SDK或者其他的集成过程。

这样做非常适合做虚拟化环境监控系统，比如VM、Docker、Kubernetes等。输出被监控组件信息的HTTP接口被叫做exporter 。目前互联网公司常用的组件大部分都有exporter可以直接使用，比如Varnish、Haproxy、Nginx、MySQL、Linux系统信息(包括磁盘、内存、CPU、网络等等)。

Prometheus三大套件

• Server 主要负责数据采集和存储，提供PromQL查询语言的支持。
• Alertmanager 警告管理器，用来进行报警。
• Push Gateway 支持临时性Job主动推送指标的中间网关。

服务过程

• Prometheus Daemon负责定时去目标上抓取metrics(指标)数据，每个抓取目标需要暴露一个http服务的接口给它定时抓取。Prometheus支持通过配置文件、文本文件、Zookeeper、Consul、DNS SRV Lookup等方式指定抓取目标。Prometheus采用PULL的方式进行监控，即服务器可以直接通过目标PULL数据或者间接地通过中间网关来Push数据。
• Prometheus在本地存储抓取的所有数据，并通过一定规则进行清理和整理数据，并把得到的结果存储到新的时间序列中。
• Prometheus通过PromQL和其他API可视化地展示收集的数据。Prometheus支持很多方式的图表可视化，例如Grafana、自带的Promdash以及自身提供的模版引擎等等。Prometheus还提供HTTP API的查询方式，自定义所需要的输出。
• PushGateway支持Client主动推送metrics到PushGateway，而Prometheus只是定时去Gateway上抓取数据。
• Alertmanager是独立于Prometheus的一个组件，可以支持Prometheus的查询语句，提供十分灵活的报警方式。

kube-prometheus部署

kube-prometheus的GitHub地址：

https://github.com/coreos/kube-prometheus/

本次我们选择release-0.2版本，而不是其他版本。

kube-prometheus下载与配置修改

下载

1 [root@k8s-master prometheus]# pwd
2 /root/k8s_practice/prometheus
3 [root@k8s-master prometheus]#
4 [root@k8s-master prometheus]# wget https://github.com/coreos/kube-prometheus/archive/v0.2.0.tar.gz
5 [root@k8s-master prometheus]# tar xf v0.2.0.tar.gz
6 [root@k8s-master prometheus]# ll
7 total 432
8 drwxrwxr-x 10 root root   4096 Sep 13  2019 kube-prometheus-0.2.0
9 -rw-r--r--  1 root root 200048 Jul 19 11:41 v0.2.0.tar.gz

配置修改

 1 # 当前所在目录
 2 [root@k8s-master manifests]# pwd
 3 /root/k8s_practice/prometheus/kube-prometheus-0.2.0/manifests
 4 [root@k8s-master manifests]#
 5 # 配置修改1
 6 [root@k8s-master manifests]# vim grafana-service.yaml
 7 apiVersion: v1
 8 kind: Service
 9 metadata:
10   labels:
11     app: grafana
12   name: grafana
13   namespace: monitoring
14 spec:
15   type: NodePort   # 添加内容
16   ports:
17   - name: http
18     port: 3000
19     targetPort: http
20     nodePort: 30100   # 添加内容
21   selector:
22     app: grafana
23 [root@k8s-master manifests]#
24 # 配置修改2
25 [root@k8s-master manifests]# vim prometheus-service.yaml
26 apiVersion: v1
27 kind: Service
28 metadata:
29   labels:
30     prometheus: k8s
31   name: prometheus-k8s
32   namespace: monitoring
33 spec:
34   type: NodePort   # 添加内容
35   ports:
36   - name: web
37     port: 9090
38     targetPort: web
39     nodePort: 30200   # 添加内容
40   selector:
41     app: prometheus
42     prometheus: k8s
43   sessionAffinity: ClientIP
44 [root@k8s-master manifests]#
45 # 配置修改3
46 [root@k8s-master manifests]# vim alertmanager-service.yaml
47 apiVersion: v1
48 kind: Service
49 metadata:
50   labels:
51     alertmanager: main
52   name: alertmanager-main
53   namespace: monitoring
54 spec:
55   type: NodePort   # 添加内容
56   ports:
57   - name: web
58     port: 9093
59     targetPort: web
60     nodePort: 30300   # 添加内容
61   selector:
62     alertmanager: main
63     app: alertmanager
64   sessionAffinity: ClientIP
65 [root@k8s-master manifests]#
66 # 配置修改4
67 [root@k8s-master manifests]# vim grafana-deployment.yaml
68 # 将apps/v1beta2 改为 apps/v1
69 apiVersion: apps/v1
70 kind: Deployment
71 metadata:
72   labels:
73     app: grafana
74   name: grafana
75   namespace: monitoring
76 spec:
77   replicas: 1
78   selector:
79 ………………

kube-prometheus镜像版本查看与下载

由于镜像都在国外，因此经常会下载失败。为了快速下载镜像，这里我们下载国内的镜像，然后tag为配置文件中的国外镜像名即可。

查看kube-prometheus的镜像信息

 1 # 当前工作目录
 2 [root@k8s-master manifests]# pwd
 3 /root/k8s_practice/prometheus/kube-prometheus-0.2.0/manifests
 4 [root@k8s-master manifests]#
 5 # 所有镜像信息如下
 6 [root@k8s-master manifests]# grep -riE 'quay.io|k8s.gcr|grafana/' *
 7 0prometheus-operator-deployment.yaml:        - --config-reloader-image=quay.io/coreos/configmap-reload:v0.0.1
 8 0prometheus-operator-deployment.yaml:        - --prometheus-config-reloader=quay.io/coreos/prometheus-config-reloader:v0.33.0
 9 0prometheus-operator-deployment.yaml:        image: quay.io/coreos/prometheus-operator:v0.33.0
10 alertmanager-alertmanager.yaml:  baseImage: quay.io/prometheus/alertmanager
11 grafana-deployment.yaml:      - image: grafana/grafana:6.2.2
12 kube-state-metrics-deployment.yaml:        image: quay.io/coreos/kube-rbac-proxy:v0.4.1
13 kube-state-metrics-deployment.yaml:        image: quay.io/coreos/kube-rbac-proxy:v0.4.1
14 kube-state-metrics-deployment.yaml:        image: quay.io/coreos/kube-state-metrics:v1.7.2
15 kube-state-metrics-deployment.yaml:        image: k8s.gcr.io/addon-resizer:1.8.4
16 node-exporter-daemonset.yaml:        image: quay.io/prometheus/node-exporter:v0.18.1
17 node-exporter-daemonset.yaml:        image: quay.io/coreos/kube-rbac-proxy:v0.4.1
18 prometheus-adapter-deployment.yaml:        image: quay.io/coreos/k8s-prometheus-adapter-amd64:v0.4.1
19 prometheus-prometheus.yaml:  baseImage: quay.io/prometheus/prometheus
20 ##### 由上可知alertmanager和prometheus的镜像版本未显示
21 ### 获取alertmanager镜像版本信息
22 [root@k8s-master manifests]# cat alertmanager-alertmanager.yaml
23 apiVersion: monitoring.coreos.com/v1
24 kind: Alertmanager
25 metadata:
26   labels:
27     alertmanager: main
28   name: main
29   namespace: monitoring
30 spec:
31   baseImage: quay.io/prometheus/alertmanager
32   nodeSelector:
33     kubernetes.io/os: linux
34   replicas: 3
35   securityContext:
36     fsGroup: 2000
37     runAsNonRoot: true
38     runAsUser: 1000
39   serviceAccountName: alertmanager-main
40   version: v0.18.0
41 ##### 由上可见alertmanager的镜像版本为v0.18.0
42 ### 获取prometheus镜像版本信息
43 [root@k8s-master manifests]# cat prometheus-prometheus.yaml
44 apiVersion: monitoring.coreos.com/v1
45 kind: Prometheus
46 metadata:
47   labels:
48     prometheus: k8s
49   name: k8s
50   namespace: monitoring
51 spec:
52   alerting:
53     alertmanagers:
54     - name: alertmanager-main
55       namespace: monitoring
56       port: web
57   baseImage: quay.io/prometheus/prometheus
58   nodeSelector:
59     kubernetes.io/os: linux
60   podMonitorSelector: {}
61   replicas: 2
62   resources:
63     requests:
64       memory: 400Mi
65   ruleSelector:
66     matchLabels:
67       prometheus: k8s
68       role: alert-rules
69   securityContext:
70     fsGroup: 2000
71     runAsNonRoot: true
72     runAsUser: 1000
73   serviceAccountName: prometheus-k8s
74   serviceMonitorNamespaceSelector: {}
75   serviceMonitorSelector: {}
76   version: v2.11.0
77 ##### 由上可见prometheus的镜像版本为v2.11.0

执行脚本：镜像下载并重命名【集群所有机器执行】

 1 [root@k8s-master software]# vim download_prometheus_image.sh
 2 #!/bin/sh
 3
 4 ##### 在 master 节点和 worker 节点都要执行 【所有机器执行】
 5
 6 # 加载环境变量
 7 . /etc/profile
 8 . /etc/bashrc
 9
10 ###############################################
11 # 从国内下载 prometheus 所需镜像，并对镜像重命名
12 src_registry="registry.cn-beijing.aliyuncs.com/cloud_registry"
13 # 定义镜像集合数组
14 images=(
15     kube-rbac-proxy:v0.4.1
16     kube-state-metrics:v1.7.2
17     k8s-prometheus-adapter-amd64:v0.4.1
18     configmap-reload:v0.0.1
19     prometheus-config-reloader:v0.33.0
20     prometheus-operator:v0.33.0
21 )
22 # 循环从国内获取的Docker镜像
23 for img in ${images[@]};
24 do
25     # 从国内源下载镜像
26     docker pull ${src_registry}/$img
27     # 改变镜像名称
28     docker tag  ${src_registry}/$img quay.io/coreos/$img
29     # 删除源始镜像
30     docker rmi  ${src_registry}/$img
31     # 打印分割线
32     echo "======== $img download OK  ========"
33 done
34
35 ##### 其他镜像下载
36 image_name="alertmanager:v0.18.0"
37 docker pull ${src_registry}/${image_name}  && docker tag ${src_registry}/${image_name}  quay.io/prometheus/${image_name}  && docker rmi ${src_registry}/${image_name}
38 echo "======== ${image_name} download OK  ========"
39
40 image_name="node-exporter:v0.18.1"
41 docker pull ${src_registry}/${image_name}  && docker tag ${src_registry}/${image_name}  quay.io/prometheus/${image_name}  && docker rmi ${src_registry}/${image_name}
42 echo "======== ${image_name} download OK  ========"
43
44 image_name="prometheus:v2.11.0"
45 docker pull ${src_registry}/${image_name}  && docker tag ${src_registry}/${image_name}  quay.io/prometheus/${image_name}  && docker rmi ${src_registry}/${image_name}
46 echo "======== ${image_name} download OK  ========"
47
48 image_name="grafana:6.2.2"
49 docker pull ${src_registry}/${image_name}  && docker tag ${src_registry}/${image_name}  grafana/${image_name}             && docker rmi ${src_registry}/${image_name}
50 echo "======== ${image_name} download OK  ========"
51
52 image_name="addon-resizer:1.8.4"
53 docker pull ${src_registry}/${image_name}  && docker tag ${src_registry}/${image_name}  k8s.gcr.io/${image_name}          && docker rmi ${src_registry}/${image_name}
54 echo "======== ${image_name} download OK  ========"
55
56
57 echo "********** prometheus docker images OK! **********"

执行脚本后得到如下镜像

 1 [root@k8s-master software]# docker images | grep 'quay.io/coreos'
 2 quay.io/coreos/kube-rbac-proxy                             v0.4.1                           a9d1a87e4379        6 days ago          41.3MB
 3 quay.io/coreos/flannel                                     v0.12.0-amd64                    4e9f801d2217        4 months ago        52.8MB ## 之前已存在
 4 quay.io/coreos/kube-state-metrics                          v1.7.2                           3fd71b84d250        6 months ago        33.1MB
 5 quay.io/coreos/prometheus-config-reloader                  v0.33.0                          64751efb2200        8 months ago        17.6MB
 6 quay.io/coreos/prometheus-operator                         v0.33.0                          8f2f814d33e1        8 months ago        42.1MB
 7 quay.io/coreos/k8s-prometheus-adapter-amd64                v0.4.1                           5f0fc84e586c        15 months ago       60.7MB
 8 quay.io/coreos/configmap-reload                            v0.0.1                           3129a2ca29d7        3 years ago         4.79MB
 9 [root@k8s-master software]#
10 [root@k8s-master software]# docker images | grep 'quay.io/prometheus'
11 quay.io/prometheus/node-exporter                           v0.18.1                          d7707e6f5e95        11 days ago         22.9MB
12 quay.io/prometheus/prometheus                              v2.11.0                          de242295e225        2 months ago        126MB
13 quay.io/prometheus/alertmanager                            v0.18.0                          30594e96cbe8        10 months ago       51.9MB
14 [root@k8s-master software]#
15 [root@k8s-master software]# docker images | grep 'grafana'
16 grafana/grafana                                            6.2.2                            a532fe3b344a        9 months ago        248MB
17 [root@k8s-node01 software]#
18 [root@k8s-node01 software]# docker images | grep 'addon-resizer'
19 k8s.gcr.io/addon-resizer                                   1.8.4                            5ec630648120        20 months ago       38.3MB

kube-prometheus启动

启动prometheus

1 [root@k8s-master kube-prometheus-0.2.0]# pwd
2 /root/k8s_practice/prometheus/kube-prometheus-0.2.0
3 [root@k8s-master kube-prometheus-0.2.0]#
4 ### 如果出现异常，可以再重复执行一次或多次
5 [root@k8s-master kube-prometheus-0.2.0]# kubectl apply -f manifests/

启动后svc与pod状态查看

 1 [root@k8s-master ~]# kubectl top node
 2 NAME         CPU(cores)   CPU%   MEMORY(bytes)   MEMORY%
 3 k8s-master   152m         7%     1311Mi          35%
 4 k8s-node01   100m         5%     928Mi           54%
 5 k8s-node02   93m          4%     979Mi           56%
 6 [root@k8s-master ~]#
 7 [root@k8s-master ~]# kubectl get svc -n monitoring
 8 NAME                    TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)                      AGE
 9 alertmanager-main       NodePort    10.97.249.249    <none>        9093:30300/TCP               7m21s
10 alertmanager-operated   ClusterIP   None             <none>        9093/TCP,9094/TCP,9094/UDP   7m13s
11 grafana                 NodePort    10.101.183.103   <none>        3000:30100/TCP               7m20s
12 kube-state-metrics      ClusterIP   None             <none>        8443/TCP,9443/TCP            7m20s
13 node-exporter           ClusterIP   None             <none>        9100/TCP                     7m20s
14 prometheus-adapter      ClusterIP   10.105.174.86    <none>        443/TCP                      7m19s
15 prometheus-k8s          NodePort    10.109.179.233   <none>        9090:30200/TCP               7m19s
16 prometheus-operated     ClusterIP   None             <none>        9090/TCP                     7m3s
17 prometheus-operator     ClusterIP   None             <none>        8080/TCP                     7m21s
18 [root@k8s-master ~]#
19 [root@k8s-master ~]# kubectl get pod -n monitoring -o wide
20 NAME                                  READY   STATUS    RESTARTS   AGE     IP             NODE         NOMINATED NODE   READINESS GATES
21 alertmanager-main-0                   2/2     Running   0          2m11s   10.244.4.164   k8s-node01   <none>           <none>
22 alertmanager-main-1                   2/2     Running   0          2m11s   10.244.2.225   k8s-node02   <none>           <none>
23 alertmanager-main-2                   2/2     Running   0          2m11s   10.244.4.163   k8s-node01   <none>           <none>
24 grafana-5cd56df4cd-6d75r              1/1     Running   0          29s     10.244.2.227   k8s-node02   <none>           <none>
25 kube-state-metrics-7d4bb66d8d-gx7w4   4/4     Running   0          2m18s   10.244.2.223   k8s-node02   <none>           <none>
26 node-exporter-pl47v                   2/2     Running   0          2m17s   172.16.1.110   k8s-master   <none>           <none>
27 node-exporter-tmmbw                   2/2     Running   0          2m17s   172.16.1.111   k8s-node01   <none>           <none>
28 node-exporter-w8wd9                   2/2     Running   0          2m17s   172.16.1.112   k8s-node02   <none>           <none>
29 prometheus-adapter-c676d8764-phj69    1/1     Running   0          2m17s   10.244.2.224   k8s-node02   <none>           <none>
30 prometheus-k8s-0                      3/3     Running   1          2m1s    10.244.2.226   k8s-node02   <none>           <none>
31 prometheus-k8s-1                      3/3     Running   0          2m1s    10.244.4.165   k8s-node01   <none>           <none>
32 prometheus-operator-7559d67ff-lk86l   1/1     Running   0          2m18s   10.244.4.162   k8s-node01   <none>           <none>

kube-prometheus访问

prometheus-service访问

访问地址如下：

http://172.16.1.110:30200/

通过访问如下地址，可以看到prometheus已经成功连接上了k8s的apiserver。

http://172.16.1.110:30200/targets

查看service-discovery

http://172.16.1.110:30200/service-discovery

prometheus自己指标查看

http://172.16.1.110:30200/metrics

prometheus的WEB界面上提供了基本的查询，例如查询K8S集群中每个POD的CPU使用情况，可以使用如下查询条件查询：

1 # 直接使用 container_cpu_usage_seconds_total 可以看见有哪些字段信息
2 sum(rate(container_cpu_usage_seconds_total{image!="", pod!=""}[1m] )) by (pod)

列表页面

图形页面

grafana-service访问

访问地址如下：

http://172.16.1.110:30100/

首次登录时账号密码默认为：admin/admin

添加数据来源

得到如下页面

如上，数据来源默认是已经添加好了的

点击进入，拉到下面，再点击Test按钮，测验数据来源是否正常

之后可导入一些模板

数据信息图像化查看

异常问题解决

如果 kubectl apply -f manifests/ 出现类似如下提示：

 1 unable to recognize "manifests/alertmanager-alertmanager.yaml": no matches for kind "Alertmanager" in version "monitoring.coreos.com/v1"
 2 unable to recognize "manifests/alertmanager-serviceMonitor.yaml": no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"
 3 unable to recognize "manifests/grafana-serviceMonitor.yaml": no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"
 4 unable to recognize "manifests/kube-state-metrics-serviceMonitor.yaml": no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"
 5 unable to recognize "manifests/node-exporter-serviceMonitor.yaml": no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"
 6 unable to recognize "manifests/prometheus-operator-serviceMonitor.yaml": no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"
 7 unable to recognize "manifests/prometheus-prometheus.yaml": no matches for kind "Prometheus" in version "monitoring.coreos.com/v1"
 8 unable to recognize "manifests/prometheus-rules.yaml": no matches for kind "PrometheusRule" in version "monitoring.coreos.com/v1"
 9 unable to recognize "manifests/prometheus-serviceMonitor.yaml": no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"
10 unable to recognize "manifests/prometheus-serviceMonitorApiserver.yaml": no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"
11 unable to recognize "manifests/prometheus-serviceMonitorCoreDNS.yaml": no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"
12 unable to recognize "manifests/prometheus-serviceMonitorKubeControllerManager.yaml": no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"
13 unable to recognize "manifests/prometheus-serviceMonitorKubeScheduler.yaml": no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"
14 unable to recognize "manifests/prometheus-serviceMonitorKubelet.yaml": no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"

那么再次 kubectl apply -f manifests/ 即可；因为存在依赖。

但如果使用的是kube-prometheus：v0.3.0、v0.4.0、v0.5.0版本并出现了上面的提示【反复执行kubectl apply -f manifests/，但一直存在】，原因暂不清楚。

完毕！

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