Prometheus接入AlterManager发送邮件告警(基于K8S环境部署)

news/2024/10/22 8:36:43/

文章目录

    • 一、配置AlterManager告警发送至邮箱
    • 二、Prometheus接入AlterManager配置
    • 三、部署Prometheus+AlterManager(放到一个Pod中)

注意:请基于 Prometheus+Grafana监控K8S集群(基于K8S环境部署)文章之上做本次实验。

一、配置AlterManager告警发送至邮箱

1、创建AlterManager ConfigMap资源清单

vim alertmanager-cm.yaml
---
kind: ConfigMap
apiVersion: v1
metadata:name: alertmanagernamespace: prometheus
data:alertmanager.yml: |-global:  resolve_timeout: 1msmtp_smarthost: 'smtp.qq.com:25'smtp_from: '1507341994@qq.com'  # 从这个邮箱发送告警smtp_auth_username: '1507341994@qq.com'  # 发送告警邮箱账号smtp_auth_password: 'eptesvmdjfpcbaab'   # 邮箱验证码,用自己的别用我的!!smtp_require_tls: falseroute:   # 路由配置(将邮箱发送那个路由)group_by: [alertname]group_wait: 10sgroup_interval: 10srepeat_interval: 10mreceiver: default-receiver   # 告警发送到default-receiver接受者receivers:- name: 'default-receiver'     # 定义default-receiver接受者email_configs:- to: '1507341994@qq.com'   # 告警发送邮箱地址send_resolved: true

执行YAML资源清单:

kubectl apply -f alertmanager-cm.yaml

2、配置文件核心配置说明

  • group_by: [alertname]:采用哪个标签来作为分组依据。
  • group_wait:10s:组告警等待时间。就是告警产生后等待10s,如果有同组告警一起发出。
  • group_interval: 10s :上下两组发送告警的间隔时间。
  • repeat_interval: 10m:重复发送告警的时间,减少相同邮件的发送频率,默认是1h。
  • receiver: default-receiver:定义谁来收告警。
  • smtp_smarthost: SMTP服务器地址+端口。
  • smtp_from:指定从哪个邮箱发送报警。
  • smtp_auth_username:邮箱账号。
  • smtp_auth_password: 邮箱密码(授权码)。

二、Prometheus接入AlterManager配置

1、创建新的Prometheus ConfigMap资源清单,添加监控K8S集群告警规则

vim prometheus-alertmanager-cfg.yaml
---
kind: ConfigMap
apiVersion: v1
metadata:labels:app: prometheusname: prometheus-confignamespace: prometheus
data:prometheus.yml: |rule_files: - /etc/prometheus/rules.yml   # 告警规则位置alerting:alertmanagers:- static_configs:- targets: ["localhost:9093"] # 接入AlterManagerglobal:scrape_interval: 15sscrape_timeout: 10sevaluation_interval: 1mscrape_configs:- job_name: 'kubernetes-node'kubernetes_sd_configs:- role: noderelabel_configs:- source_labels: [__address__]regex: '(.*):10250'replacement: '${1}:9100'target_label: __address__action: replace- action: labelmapregex: __meta_kubernetes_node_label_(.+)- job_name: 'kubernetes-node-cadvisor'kubernetes_sd_configs:- role:  nodescheme: httpstls_config:ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crtbearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/tokenrelabel_configs:- action: labelmapregex: __meta_kubernetes_node_label_(.+)- target_label: __address__replacement: kubernetes.default.svc:443- source_labels: [__meta_kubernetes_node_name]regex: (.+)target_label: __metrics_path__replacement: /api/v1/nodes/${1}/proxy/metrics/cadvisor- job_name: 'kubernetes-apiserver'kubernetes_sd_configs:- role: endpointsscheme: httpstls_config:ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crtbearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/tokenrelabel_configs:- source_labels: [__meta_kubernetes_namespace, __meta_kubernetes_service_name, __meta_kubernetes_endpoint_port_name]action: keepregex: default;kubernetes;https- job_name: 'kubernetes-service-endpoints'kubernetes_sd_configs:- role: endpointsrelabel_configs:- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scrape]action: keepregex: true- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scheme]action: replacetarget_label: __scheme__regex: (https?)- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_path]action: replacetarget_label: __metrics_path__regex: (.+)- source_labels: [__address__, __meta_kubernetes_service_annotation_prometheus_io_port]action: replacetarget_label: __address__regex: ([^:]+)(?::\d+)?;(\d+)replacement: $1:$2- action: labelmapregex: __meta_kubernetes_service_label_(.+)- source_labels: [__meta_kubernetes_namespace]action: replacetarget_label: kubernetes_namespace- source_labels: [__meta_kubernetes_service_name]action: replacetarget_label: kubernetes_name - job_name: 'kubernetes-pods'    # 监控Pod配置,添加注解后才可以被发现kubernetes_sd_configs:- role: podrelabel_configs:- action: keepregex: truesource_labels:- __meta_kubernetes_pod_annotation_prometheus_io_scrape- action: replaceregex: (.+)source_labels:- __meta_kubernetes_pod_annotation_prometheus_io_pathtarget_label: __metrics_path__- action: replaceregex: ([^:]+)(?::\d+)?;(\d+)replacement: $1:$2source_labels:- __address__- __meta_kubernetes_pod_annotation_prometheus_io_porttarget_label: __address__- action: labelmapregex: __meta_kubernetes_pod_label_(.+)- action: replacesource_labels:- __meta_kubernetes_namespacetarget_label: kubernetes_namespace- action: replacesource_labels:- __meta_kubernetes_pod_nametarget_label: kubernetes_pod_name- job_name: 'kubernetes-etcd'   # 监控etcd配置scheme: httpstls_config:ca_file: /var/run/secrets/kubernetes.io/k8s-certs/etcd/ca.crtcert_file: /var/run/secrets/kubernetes.io/k8s-certs/etcd/server.crtkey_file: /var/run/secrets/kubernetes.io/k8s-certs/etcd/server.keyscrape_interval: 5sstatic_configs:- targets: ['16.32.15.200:2379']rules.yml: |  # K8S集群告警规则配置文件groups:- name: examplerules:- alert: apiserver的cpu使用率大于80%expr: rate(process_cpu_seconds_total{job=~"kubernetes-apiserver"}[1m]) * 100 > 80for: 2slabels:severity: warnningannotations:description: "{{$labels.instance}}的{{$labels.job}}组件的cpu使用率超过80%"- alert:  apiserver的cpu使用率大于90%expr: rate(process_cpu_seconds_total{job=~"kubernetes-apiserver"}[1m]) * 100 > 90for: 2slabels:severity: criticalannotations:description: "{{$labels.instance}}的{{$labels.job}}组件的cpu使用率超过90%"- alert: etcd的cpu使用率大于80%expr: rate(process_cpu_seconds_total{job=~"kubernetes-etcd"}[1m]) * 100 > 80for: 2slabels:severity: warnningannotations:description: "{{$labels.instance}}的{{$labels.job}}组件的cpu使用率超过80%"- alert:  etcd的cpu使用率大于90%expr: rate(process_cpu_seconds_total{job=~"kubernetes-etcd"}[1m]) * 100 > 90for: 2slabels:severity: criticalannotations:description: "{{$labels.instance}}的{{$labels.job}}组件的cpu使用率超过90%"- alert: kube-state-metrics的cpu使用率大于80%expr: rate(process_cpu_seconds_total{k8s_app=~"kube-state-metrics"}[1m]) * 100 > 80for: 2slabels:severity: warnningannotations:description: "{{$labels.instance}}的{{$labels.k8s_app}}组件的cpu使用率超过80%"value: "{{ $value }}%"threshold: "80%"      - alert: kube-state-metrics的cpu使用率大于90%expr: rate(process_cpu_seconds_total{k8s_app=~"kube-state-metrics"}[1m]) * 100 > 0for: 2slabels:severity: criticalannotations:description: "{{$labels.instance}}的{{$labels.k8s_app}}组件的cpu使用率超过90%"value: "{{ $value }}%"threshold: "90%"      - alert: coredns的cpu使用率大于80%expr: rate(process_cpu_seconds_total{k8s_app=~"kube-dns"}[1m]) * 100 > 80for: 2slabels:severity: warnningannotations:description: "{{$labels.instance}}的{{$labels.k8s_app}}组件的cpu使用率超过80%"value: "{{ $value }}%"threshold: "80%"      - alert: coredns的cpu使用率大于90%expr: rate(process_cpu_seconds_total{k8s_app=~"kube-dns"}[1m]) * 100 > 90for: 2slabels:severity: criticalannotations:description: "{{$labels.instance}}的{{$labels.k8s_app}}组件的cpu使用率超过90%"value: "{{ $value }}%"threshold: "90%"      - alert: kube-proxy打开句柄数>600expr: process_open_fds{job=~"kubernetes-kube-proxy"}  > 600for: 2slabels:severity: warnningannotations:description: "{{$labels.instance}}的{{$labels.job}}打开句柄数>600"value: "{{ $value }}"- alert: kube-proxy打开句柄数>1000expr: process_open_fds{job=~"kubernetes-kube-proxy"}  > 1000for: 2slabels:severity: criticalannotations:description: "{{$labels.instance}}的{{$labels.job}}打开句柄数>1000"value: "{{ $value }}"- alert: kubernetes-schedule打开句柄数>600expr: process_open_fds{job=~"kubernetes-schedule"}  > 600for: 2slabels:severity: warnningannotations:description: "{{$labels.instance}}的{{$labels.job}}打开句柄数>600"value: "{{ $value }}"- alert: kubernetes-schedule打开句柄数>1000expr: process_open_fds{job=~"kubernetes-schedule"}  > 1000for: 2slabels:severity: criticalannotations:description: "{{$labels.instance}}的{{$labels.job}}打开句柄数>1000"value: "{{ $value }}"- alert: kubernetes-controller-manager打开句柄数>600expr: process_open_fds{job=~"kubernetes-controller-manager"}  > 600for: 2slabels:severity: warnningannotations:description: "{{$labels.instance}}的{{$labels.job}}打开句柄数>600"value: "{{ $value }}"- alert: kubernetes-controller-manager打开句柄数>1000expr: process_open_fds{job=~"kubernetes-controller-manager"}  > 1000for: 2slabels:severity: criticalannotations:description: "{{$labels.instance}}的{{$labels.job}}打开句柄数>1000"value: "{{ $value }}"- alert: kubernetes-apiserver打开句柄数>600expr: process_open_fds{job=~"kubernetes-apiserver"}  > 600for: 2slabels:severity: warnningannotations:description: "{{$labels.instance}}的{{$labels.job}}打开句柄数>600"value: "{{ $value }}"- alert: kubernetes-apiserver打开句柄数>1000expr: process_open_fds{job=~"kubernetes-apiserver"}  > 1000for: 2slabels:severity: criticalannotations:description: "{{$labels.instance}}的{{$labels.job}}打开句柄数>1000"value: "{{ $value }}"- alert: kubernetes-etcd打开句柄数>600expr: process_open_fds{job=~"kubernetes-etcd"}  > 600for: 2slabels:severity: warnningannotations:description: "{{$labels.instance}}的{{$labels.job}}打开句柄数>600"value: "{{ $value }}"- alert: kubernetes-etcd打开句柄数>1000expr: process_open_fds{job=~"kubernetes-etcd"}  > 1000for: 2slabels:severity: criticalannotations:description: "{{$labels.instance}}的{{$labels.job}}打开句柄数>1000"value: "{{ $value }}"- alert: corednsexpr: process_open_fds{k8s_app=~"kube-dns"}  > 600for: 2slabels:severity: warnning annotations:description: "插件{{$labels.k8s_app}}({{$labels.instance}}): 打开句柄数超过600"value: "{{ $value }}"- alert: corednsexpr: process_open_fds{k8s_app=~"kube-dns"}  > 1000for: 2slabels:severity: criticalannotations:description: "插件{{$labels.k8s_app}}({{$labels.instance}}): 打开句柄数超过1000"value: "{{ $value }}"- alert: kube-proxyexpr: process_virtual_memory_bytes{job=~"kubernetes-kube-proxy"}  > 2000000000for: 2slabels:severity: warnningannotations:description: "组件{{$labels.job}}({{$labels.instance}}): 使用虚拟内存超过2G"value: "{{ $value }}"- alert: schedulerexpr: process_virtual_memory_bytes{job=~"kubernetes-schedule"}  > 2000000000for: 2slabels:severity: warnningannotations:description: "组件{{$labels.job}}({{$labels.instance}}): 使用虚拟内存超过2G"value: "{{ $value }}"- alert: kubernetes-controller-managerexpr: process_virtual_memory_bytes{job=~"kubernetes-controller-manager"}  > 2000000000for: 2slabels:severity: warnningannotations:description: "组件{{$labels.job}}({{$labels.instance}}): 使用虚拟内存超过2G"value: "{{ $value }}"- alert: kubernetes-apiserverexpr: process_virtual_memory_bytes{job=~"kubernetes-apiserver"}  > 2000000000for: 2slabels:severity: warnningannotations:description: "组件{{$labels.job}}({{$labels.instance}}): 使用虚拟内存超过2G"value: "{{ $value }}"- alert: kubernetes-etcdexpr: process_virtual_memory_bytes{job=~"kubernetes-etcd"}  > 2000000000for: 2slabels:severity: warnningannotations:description: "组件{{$labels.job}}({{$labels.instance}}): 使用虚拟内存超过2G"value: "{{ $value }}"- alert: kube-dnsexpr: process_virtual_memory_bytes{k8s_app=~"kube-dns"}  > 2000000000for: 2slabels:severity: warnningannotations:description: "插件{{$labels.k8s_app}}({{$labels.instance}}): 使用虚拟内存超过2G"value: "{{ $value }}"- alert: HttpRequestsAvgexpr: sum(rate(rest_client_requests_total{job=~"kubernetes-kube-proxy|kubernetes-kubelet|kubernetes-schedule|kubernetes-control-manager|kubernetes-apiservers"}[1m]))  > 1000for: 2slabels:team: adminannotations:description: "组件{{$labels.job}}({{$labels.instance}}): TPS超过1000"value: "{{ $value }}"threshold: "1000"   - alert: Pod_restartsexpr: kube_pod_container_status_restarts_total{namespace=~"kube-system|default|monitor-sa"} > 0for: 2slabels:severity: warnningannotations:description: "在{{$labels.namespace}}名称空间下发现{{$labels.pod}}这个pod下的容器{{$labels.container}}被重启,这个监控指标是由{{$labels.instance}}采集的"value: "{{ $value }}"threshold: "0"- alert: Pod_waitingexpr: kube_pod_container_status_waiting_reason{namespace=~"kube-system|default"} == 1for: 2slabels:team: adminannotations:description: "空间{{$labels.namespace}}({{$labels.instance}}): 发现{{$labels.pod}}下的{{$labels.container}}启动异常等待中"value: "{{ $value }}"threshold: "1"   - alert: Pod_terminatedexpr: kube_pod_container_status_terminated_reason{namespace=~"kube-system|default|monitor-sa"} == 1for: 2slabels:team: adminannotations:description: "空间{{$labels.namespace}}({{$labels.instance}}): 发现{{$labels.pod}}下的{{$labels.container}}被删除"value: "{{ $value }}"threshold: "1"- alert: Etcd_leaderexpr: etcd_server_has_leader{job="kubernetes-etcd"} == 0for: 2slabels:team: adminannotations:description: "组件{{$labels.job}}({{$labels.instance}}): 当前没有leader"value: "{{ $value }}"threshold: "0"- alert: Etcd_leader_changesexpr: rate(etcd_server_leader_changes_seen_total{job="kubernetes-etcd"}[1m]) > 0for: 2slabels:team: adminannotations:description: "组件{{$labels.job}}({{$labels.instance}}): 当前leader已发生改变"value: "{{ $value }}"threshold: "0"- alert: Etcd_failedexpr: rate(etcd_server_proposals_failed_total{job="kubernetes-etcd"}[1m]) > 0for: 2slabels:team: adminannotations:description: "组件{{$labels.job}}({{$labels.instance}}): 服务失败"value: "{{ $value }}"threshold: "0"- alert: Etcd_db_total_sizeexpr: etcd_debugging_mvcc_db_total_size_in_bytes{job="kubernetes-etcd"} > 10000000000for: 2slabels:team: adminannotations:description: "组件{{$labels.job}}({{$labels.instance}}):db空间超过10G"value: "{{ $value }}"threshold: "10G"- alert: Endpoint_readyexpr: kube_endpoint_address_not_ready{namespace=~"kube-system|default"} == 1for: 2slabels:team: adminannotations:description: "空间{{$labels.namespace}}({{$labels.instance}}): 发现{{$labels.endpoint}}不可用"value: "{{ $value }}"threshold: "1"- name: 物理节点状态-监控告警rules:- alert: 物理节点cpu使用率expr: 100-avg(irate(node_cpu_seconds_total{mode="idle"}[5m])) by(instance)*100 > 90for: 2slabels:severity: ccriticalannotations:summary: "{{ $labels.instance }}cpu使用率过高"description: "{{ $labels.instance }}的cpu使用率超过90%,当前使用率[{{ $value }}],需要排查处理" - alert: 物理节点内存使用率expr: (node_memory_MemTotal_bytes - (node_memory_MemFree_bytes + node_memory_Buffers_bytes + node_memory_Cached_bytes)) / node_memory_MemTotal_bytes * 100 > 90for: 2slabels:severity: criticalannotations:summary: "{{ $labels.instance }}内存使用率过高"description: "{{ $labels.instance }}的内存使用率超过90%,当前使用率[{{ $value }}],需要排查处理"- alert: InstanceDownexpr: up == 0for: 2slabels:severity: criticalannotations:   summary: "{{ $labels.instance }}: 服务器宕机"description: "{{ $labels.instance }}: 服务器延时超过2分钟"- alert: 物理节点磁盘的IO性能expr: 100-(avg(irate(node_disk_io_time_seconds_total[1m])) by(instance)* 100) < 60for: 2slabels:severity: criticalannotations:summary: "{{$labels.mountpoint}} 流入磁盘IO使用率过高!"description: "{{$labels.mountpoint }} 流入磁盘IO大于60%(目前使用:{{$value}})"- alert: 入网流量带宽expr: ((sum(rate (node_network_receive_bytes_total{device!~'tap.*|veth.*|br.*|docker.*|virbr*|lo*'}[5m])) by (instance)) / 100) > 102400for: 2slabels:severity: criticalannotations:summary: "{{$labels.mountpoint}} 流入网络带宽过高!"description: "{{$labels.mountpoint }}流入网络带宽持续5分钟高于100M. RX带宽使用率{{$value}}"- alert: 出网流量带宽expr: ((sum(rate (node_network_transmit_bytes_total{device!~'tap.*|veth.*|br.*|docker.*|virbr*|lo*'}[5m])) by (instance)) / 100) > 102400for: 2slabels:severity: criticalannotations:summary: "{{$labels.mountpoint}} 流出网络带宽过高!"description: "{{$labels.mountpoint }}流出网络带宽持续5分钟高于100M. RX带宽使用率{{$value}}"- alert: TCP会话expr: node_netstat_Tcp_CurrEstab > 1000for: 2slabels:severity: criticalannotations:summary: "{{$labels.mountpoint}} TCP_ESTABLISHED过高!"description: "{{$labels.mountpoint }} TCP_ESTABLISHED大于1000%(目前使用:{{$value}}%)"- alert: 磁盘容量expr: 100-(node_filesystem_free_bytes{fstype=~"ext4|xfs"}/node_filesystem_size_bytes {fstype=~"ext4|xfs"}*100) > 80for: 2slabels:severity: criticalannotations:summary: "{{$labels.mountpoint}} 磁盘分区使用率过高!"description: "{{$labels.mountpoint }} 磁盘分区使用大于80%(目前使用:{{$value}}%)"

执行资源清单:

kubectl apply -f prometheus-alertmanager-cfg.yaml

2、由于在prometheus中新增了etcd,所以生成一个etcd-certs,这个在部署prometheus需要

kubectl -n prometheus create secret generic etcd-certs --from-file=/etc/kubernetes/pki/etcd/server.key  --from-file=/etc/kubernetes/pki/etcd/server.crt --from-file=/etc/kubernetes/pki/etcd/ca.crt

三、部署Prometheus+AlterManager(放到一个Pod中)

1、创建deployment资源

vim prometheus-alertmanager-deploy.yaml
---
apiVersion: apps/v1
kind: Deployment
metadata:name: prometheus-servernamespace: prometheuslabels:app: prometheus
spec:replicas: 1selector:matchLabels:app: prometheuscomponent: server#matchExpressions:#- {key: app, operator: In, values: [prometheus]}#- {key: component, operator: In, values: [server]}template:metadata:labels:app: prometheuscomponent: serverannotations:prometheus.io/scrape: 'false'spec:nodeName: node-1 # 调度到node-1节点serviceAccountName: prometheus # 指定sa服务账号containers:- name: prometheusimage: prom/prometheus:v2.33.5imagePullPolicy: IfNotPresentcommand:- "/bin/prometheus"args:- "--config.file=/etc/prometheus/prometheus.yml"- "--storage.tsdb.path=/prometheus"- "--storage.tsdb.retention=24h"- "--web.enable-lifecycle"ports:- containerPort: 9090protocol: TCPvolumeMounts:- mountPath: /etc/prometheusname: prometheus-config- mountPath: /prometheus/name: prometheus-storage-volume- name: k8s-certsmountPath: /var/run/secrets/kubernetes.io/k8s-certs/etcd/- name: alertmanager#image: prom/alertmanager:v0.14.0image: prom/alertmanager:v0.23.0imagePullPolicy: IfNotPresentargs:- "--config.file=/etc/alertmanager/alertmanager.yml"- "--log.level=debug"ports:- containerPort: 9093protocol: TCPname: alertmanagervolumeMounts:- name: alertmanager-configmountPath: /etc/alertmanager- name: alertmanager-storagemountPath: /alertmanager- name: localtimemountPath: /etc/localtimevolumes:- name: prometheus-configconfigMap:name: prometheus-config- name: prometheus-storage-volumehostPath:path: /datatype: Directory- name: k8s-certssecret:secretName: etcd-certs- name: alertmanager-configconfigMap:name: alertmanager- name: alertmanager-storagehostPath:path: /data/alertmanagertype: DirectoryOrCreate- name: localtimehostPath:path: /usr/share/zoneinfo/Asia/Shanghai

执行YAML资源清单:

kubectl apply -f prometheus-alertmanager-deploy.yaml

2、创建AlterManager SVC资源

vim alertmanager-svc.yaml 
---
apiVersion: v1
kind: Service
metadata:labels:name: prometheuskubernetes.io/cluster-service: 'true'name: alertmanagernamespace: prometheus
spec:ports:- name: alertmanagernodePort: 30066port: 9093protocol: TCPtargetPort: 9093selector:app: prometheussessionAffinity: Nonetype: NodePort

执行YAML资源清单:

kubectl apply -f alertmanager-svc.yaml 

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