Prometheus Operator不同于Prometheus，Prometheus Operator是 CoreOS 开源的一套用于管理在 Kubernetes 集群上的 Prometheus 控制器，它是为了简化在 Kubernetes 上部署、管理和运行 Prometheus 和 Alertmanager 集群。
官方提供的架构图：
kubernetes也在官方的github上关于使用prometheus监控的建议：
地址：https://github.com/kubernetes/kubernetes/tree/master/cluster/addons/prometheus
相关服务说明：
Operator： Operator 资源会根据自定义资源（Custom Resource Definition / CRDs）来部署和管理 Prometheus Server，同时监控这些自定义资源事件的变化来做相应的处理，是整个系统的控制中心。
Prometheus： Prometheus 资源是声明性地描述 Prometheus 部署的期望状态。
Prometheus Server： Operator 根据自定义资源 Prometheus 类型中定义的内容而部署的 Prometheus Server 集群，这些自定义资源可以看作是用来管理 Prometheus Server 集群的 StatefulSets 资源。
ServiceMonitor： ServiceMonitor 也是一个自定义资源，它描述了一组被 Prometheus 监控的 targets 列表。该资源通过 Labels 来选取对应的 Service Endpoint，让 Prometheus Server 通过选取的 Service 来获取 Metrics 信息。
Service： Service 资源主要用来对应 Kubernetes 集群中的 Metrics Server Pod，来提供给 ServiceMonitor 选取让 Prometheus Server 来获取信息。简单的说就是 Prometheus 监控的对象，例如之前了解的 Node Exporter Service、Mysql Exporter Service 等等。
Alertmanager： Alertmanager 也是一个自定义资源类型，由 Operator 根据资源描述内容来部署 Alertmanager 集群
1、下载配置文件
官方地址：https://github.com/coreos/kube-prometheus
因为整个项目并没有多大，这里我把整个项目克隆下来，你也可以下载单独的文件，把https://github.com/coreos/kube-prometheus/tree/master/manifests下面的文件全部下载到本地。
[root@k8s-master01 k8s]# git clone https://github.com/coreos/kube-prometheus.git
2、部署
2.1 配置清单yml文件归档
## 因为官方把所有资源配置文件都放到一个文件目录下，这里我们为了方便，把不同服务的清单文件分别归档
[root@k8s-master01 ~]# cd /opt/k8s/kube-prometheus/manifests
[root@k8s-master01 manifests]# mkdir serviceMonitor operator grafana kube-state-metrics alertmanager node-exporter adapter prometheus
[root@k8s-master01 manifests]# mv *-serviceMonitor* serviceMonitor/
[root@k8s-master01 manifests]# mv 0prometheus-operator* operator/
[root@k8s-master01 manifests]# mv grafana-* grafana/
[root@k8s-master01 manifests]# mv kube-state-metrics-* kube-state-metrics/
[root@k8s-master01 manifests]# mv alertmanager-* alertmanager/
[root@k8s-master01 manifests]# mv node-exporter-* node-exporter/
[root@k8s-master01 manifests]# mv prometheus-adapter-* adapter/
[root@k8s-master01 manifests]# mv prometheus-* prometheus/
2.2 部署operator
## 首先创建prometheus监控专有命名空间
[root@k8s-master01 manifests]# kubectl apply -f 00namespace-namespace.yaml
## 部署operator
[root@k8s-master01 manifests]# kubectl apply -f operator/
## 查看pod运行情况，配置清单中镜像仓库地址为，quay.io,所以无需进行其它操作
[root@k8s-master01 manifests]# kubectl get pods -n monitoring
NAME READY STATUS RESTARTS AGE
prometheus-operator-69bd579bf9-mjsxz 1/1 Running 0 20s
2.3 部署metrics
这里部署metrics之前，需要先确定集群中kube-apiserver是否已经开启聚合(支持集群接入第三方api)以及其它组件参数是否正确，否则会导致无法获取数据的情况出现，具体请参考前面文章K8S从入门到放弃系列-(13)Kubernetes集群mertics-server部署.
## 这里addon-resizer服务镜像使用的是google的仓库，我们修改为阿里云仓库
[root@k8s-master01 manifests]# vim kube-state-metrics/kube-state-metrics-deployment.yaml
#image: k8s.gcr.io/addon-resizer:1.8.4 ## 原有配置，注释修改为一下地址
image: registry.aliyuncs.com/google_containers/addon-resizer:1.8.4
[root@k8s-master01 kube-state-metrics]# kubectl apply -f kube-state-metrics/
2.4 部署其它组件
其它组件按照以上部署即可，镜像无需*均可以正常下载。镜像下载速度取决与本地网络状况。
[root@k8s-master01 kube-state-metrics]# kubectl apply -f adapter/
[root@k8s-master01 kube-state-metrics]# kubectl apply -f alertmanager/
[root@k8s-master01 kube-state-metrics]# kubectl apply -f node-exporter/
[root@k8s-master01 kube-state-metrics]# kubectl apply -f grafana/
[root@k8s-master01 kube-state-metrics]# kubectl apply -f prometheus/
[root@k8s-master01 kube-state-metrics]# kubectl apply -f serviceMonitor/ ## 部署完成后，可以查看下个资源运行部署详情
NAME READY STATUS RESTARTS AGE
pod/grafana-558647b59-bhqmq 1/1 Running 0 94m
pod/kube-state-metrics-79d4446fb5-5mj7d 4/4 Running 0 98m
pod/node-exporter-4xq5t 2/2 Running 0 111m
pod/node-exporter-9b88m 2/2 Running 0 111m
pod/node-exporter-fdntx 2/2 Running 0 111m
pod/node-exporter-mwbxj 2/2 Running 0 111m
pod/node-exporter-tn7tl 2/2 Running 0 111m
pod/prometheus-adapter-57c497c557-vbgxd 1/1 Running 0 144m
pod/prometheus-k8s-0 3/3 Running 0 96m
pod/prometheus-k8s-1 3/3 Running 0 96m
pod/prometheus-operator-69bd579bf9-mjsxz 1/1 Running 0 155m
service/grafana ClusterIP 10.254.42.208 <none> 3000/TCP 94m
service/kube-state-metrics ClusterIP None <none> 8443/TCP,9443/TCP 104m
service/node-exporter ClusterIP None <none> 9100/TCP 111m
service/prometheus-adapter ClusterIP 10.254.107.95 <none> 443/TCP 144m
service/prometheus-k8s ClusterIP 10.254.82.246 <none> 9090/TCP 96m
service/prometheus-operated ClusterIP None <none> 9090/TCP 96m
service/prometheus-operator ClusterIP None <none> 8080/TCP 156m
daemonset.apps/node-exporter 5 5 5 5 5 beta.kubernetes.io/os=linux 111m
deployment.apps/grafana 1/1 1 1 94m
deployment.apps/kube-state-metrics 1/1 1 1 98m
deployment.apps/prometheus-adapter 1/1 1 1 144m
deployment.apps/prometheus-operator 1/1 1 1 156m
replicaset.apps/grafana-558647b59 1 1 1 94m
replicaset.apps/kube-state-metrics-5b86559fd5 0 0 0 98m
replicaset.apps/kube-state-metrics-79d4446fb5 1 1 1 98m
replicaset.apps/prometheus-adapter-57c497c557 1 1 1 144m
replicaset.apps/prometheus-operator-69bd579bf9 1 1 1 156m
statefulset.apps/prometheus-k8s 2/2 96m
3、创建ingress服务
这里我没有采用NodePort的方式暴露服务，而是使用的Ingress，具体Ingress安装部署，查看前面文章K8S从入门到放弃系列-(15)Kubernetes集群Ingress部署
3.1 编辑ingress配置文件
### 配置prometheus、grafana、alertmanager三个服务可视化web界面Ingress访问
[root@k8s-master01 manifests]# cat ingress-all-svc.yml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: prometheus-ing
namespace: monitoring
spec:
rules:
- host: prometheus.monitoring.k8s.local
http:
paths:
- backend:
serviceName: prometheus-k8s
servicePort:
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: grafana-ing
namespace: monitoring
spec:
rules:
- host: grafana.monitoring.k8s.local
http:
paths:
- backend:
serviceName: grafana
servicePort:
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: alertmanager-ing
namespace: monitoring
spec:
rules:
- host: alertmanager.monitoring.k8s.local
http:
paths:
- backend:
serviceName: alertmanager-main
servicePort: 9093
[root@k8s-master01 manifests]# kubectl apply -f ingress-all-svc.yml
## 可以看到三个服务对应域名已经创建
[root@k8s-master01 manifests]# kubectl get ingress -n monitoring
NAME HOSTS ADDRESS PORTS AGE
alertmanager-ing alertmanager.monitoring.k8s.local 80 3d21h
grafana-ing grafana.monitoring.k8s.local 80 3d21h
prometheus-ing prometheus.monitoring.k8s.local 80 3d21h
## 查看ingress暴露svc端口，后面访问需要加上端口号
[root@k8s-master01 manifests]# kubectl get svc -n ingress-nginx
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
ingress-nginx NodePort 10.254.102.184 <none> 80:33848/TCP,443:45891/TCP 4d3h
4、访问
配置本地host解析，路径：C:\Windows\System32\drivers\etc\hosts
172.16.11.123 prometheus.monitoring.k8s.local
172.16.11.123 grafana.monitoring.k8s.local
172.16.11.123 alertmanager.monitoring.k8s.local
浏览器打开http://prometheus.monitoring.k8s.local:33848,可以看到已经监控的主机及pod
4.2 问题
这里部署好后，查看prometheus target界面，看到kube-controller-manager、kube-scheduler目标主机都为0
原因分析：
这是因为serviceMonitor选择svc时，是根据labels标签选取，而在指定的命名空间(kube-system)，并没有对应的标签。kube-apiserver之所以正常是因为kube-apiserver 服务 namespace 在default使用默认svc kubernetes。其余组件服务在kube-system 空间 ，需要单独创建svc。
## 查看serviceMonitor选取svc规则
[root@k8s-master01 manifests]# grep - selector serviceMonitor/prometheus-serviceMonitorKube*
serviceMonitor/prometheus-serviceMonitorKubeControllerManager.yaml- matchNames:
serviceMonitor/prometheus-serviceMonitorKubeControllerManager.yaml- - kube-system
serviceMonitor/prometheus-serviceMonitorKubeControllerManager.yaml: selector:
serviceMonitor/prometheus-serviceMonitorKubeControllerManager.yaml- matchLabels:
serviceMonitor/prometheus-serviceMonitorKubeControllerManager.yaml- k8s-app: kube-controller-manager
--
serviceMonitor/prometheus-serviceMonitorKubelet.yaml- matchNames:
serviceMonitor/prometheus-serviceMonitorKubelet.yaml- - kube-system
serviceMonitor/prometheus-serviceMonitorKubelet.yaml: selector:
serviceMonitor/prometheus-serviceMonitorKubelet.yaml- matchLabels:
serviceMonitor/prometheus-serviceMonitorKubelet.yaml- k8s-app: kubelet
--
serviceMonitor/prometheus-serviceMonitorKubeScheduler.yaml- matchNames:
serviceMonitor/prometheus-serviceMonitorKubeScheduler.yaml- - kube-system
serviceMonitor/prometheus-serviceMonitorKubeScheduler.yaml: selector:
serviceMonitor/prometheus-serviceMonitorKubeScheduler.yaml- matchLabels:
serviceMonitor/prometheus-serviceMonitorKubeScheduler.yaml- k8s-app: kube-scheduler
##查看kube-system命名空间下的svc，可以看到并没有kube-scheduler、kube-controller-manager
[root@k8s-master01 manifests]# kubectl -n kube-system get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kube-dns ClusterIP 10.254.0.2 <none> 53/UDP,53/TCP,9153/TCP 49d
kubelet ClusterIP None <none> 10250/TCP 4d2h
但是却有对应的ep(没有带任何label)被创建，另外如果你的集群是kubeadm部署的就没有kubelet的ep，二进制部署的会有。
[root@k8s-master01 manifests]# kubectl get ep -n kube-system
NAME ENDPOINTS AGE
kube-controller-manager <none> 6m38s
kube-dns 10.254.88.22:53,10.254.96.207:53,10.254.88.22:53 + 3 more... 49d
kube-scheduler <none> 6m39s
kubelet 172.16.11.120:10255,172.16.11.121:10255,172.16.11.122:10255 + 12 more... 4d3h
解决：
1）创建kube-controller-manager、kube-scheduler两个组件服务的集群svc，需要打上对应的标签，使其可以被servicemonitor选中。
## svc服务
[root@k8s-master01 manifests]# cat controller-scheduler-svc.yml
apiVersion: v1
kind: Service
metadata:
namespace: kube-system
name: kube-controller-manager
labels:
k8s-app: kube-controller-manager
spec:
selector:
component: kube-controller-manager
type: ClusterIP
clusterIP: None
ports:
- name: http-metrics
port:
targetPort:
protocol: TCP
---
apiVersion: v1
kind: Service
metadata:
namespace: kube-system
name: kube-scheduler
labels:
k8s-app: kube-scheduler
spec:
selector:
component: kube-scheduler
type: ClusterIP
clusterIP: None
ports:
- name: http-metrics
port:
targetPort:
protocol: TCP
## ep修改，二进制部署需要我们把svc对应的ep的属性修改下，ip地址修改为自己的集群ip
[root@k8s-master01 manifests]# cat controller-scheduler-ep.yml
apiVersion: v1
kind: Endpoints
metadata:
labels:
k8s-app: kube-controller-manager
name: kube-controller-manager
namespace: kube-system
subsets:
- addresses:
- ip: 172.16.11.120
- ip: 172.16.11.121
- ip: 172.16.11.122
ports:
- name: http-metrics
port: 10252
protocol: TCP
---
apiVersion: v1
kind: Endpoints
metadata:
labels:
k8s-app: kube-scheduler
name: kube-scheduler
namespace: kube-system
subsets:
- addresses:
- ip: 172.16.11.120
- ip: 172.16.11.121
- ip: 172.16.11.122
ports:
- name: http-metrics
port: 10251
protocol: TCP
## 查看创建资源
NAME ENDPOINTS AGE
endpoints/kube-controller-manager 172.16.11.120:10252,172.16.11.121:10252,172.16.11.122:10252 18m
endpoints/kube-dns 10.254.88.22:53,10.254.96.207:53,10.254.88.22:53 + 3 more... 49d
endpoints/kube-scheduler 172.16.11.120:10251,172.16.11.121:10251,172.16.11.122:10251 18m
endpoints/kubelet 172.16.11.120:10255,172.16.11.121:10255,172.16.11.122:10255 + 12 more... 4d3h
service/kube-controller-manager ClusterIP None <none> 10252/TCP 12m
service/kube-dns ClusterIP 10.254.0.2 <none> 53/UDP,53/TCP,9153/TCP 49d
service/kube-scheduler ClusterIP None <none> 10251/TCP 12m
service/kubelet ClusterIP None <none> 10250/TCP 4d3h
2）修改kube-controller-manager、kube-scheduler监听地址使其能访问 metrics。
## 修改为0.0.0.0
--address=0.0.0.0
修改完，重启服务，再次查看prometheus targets界面，可以看到都已经正常监听目标主机服务
5、grafana监控查看
1）可以看到grafana已经有多个dashboard页面
2）可以正常监控
