k8s(八)、监控--Prometheus告警篇（告警消息对接钉钉接口）

小鱼儿 2022-05-21 00:38 1814阅读 0赞

## 前言 ##

承接上章[k8s(七)、Prometheus部署篇][k8s_Prometheus]，在上章的基础上，本章介绍Prometheus告警相关配置。

## 一、Querying expr & PromQL ##

在了解告警规则之前，首先得了解Prometheus的数据查询表达式，来获取metric数据是否到达告警阈(ps:这个字儿念yu，第四声，不念第二声的fa)值。

**Overview**  
Prometheus提供了一种功能性表达式语言，能够让用户实时的选择和聚合时间序列的数据。表达式返回的结果可以被显示为曲线图，也可以在prometheus浏览器中显示为表格，或者通过HTTP API经由外部系统处理。

**表达式语言类型**  
Prometheus表达式或子表达式可以评估为一下四种类型之一：  
即时向量（Instant vector） - 包含每个时间序列单个样品的一组时间序列，共享相同的时间戳  
范围向量（Range vector） - 包含一个范围内数据点的一组时间序列  
标量（Scalar） - 一个简单的数字浮点值  
字符串（String） - 一个简单的字符串值；当前未使用  
根据使用情况（例如画图或者显示表达式的输出），只有某些类型是合法的，例如，即时向量表达式是可以画图的唯一类型。

**时间序列选择器**

**即时向量选择**  
即时向量选择器允许选择一组时间序列，或者某个给定的时间戳的样本数据。下面这个例子选择了具有时间序列的http\_requests\_total metric对象：

http_requests_total

你可以通过附加一组标签，并用\{\}括起来，来进一步筛选这些时间序列。下面这个例子只选择有http\_requests\_total名称的、有prometheus工作标签的、有canary组标签的时间序列：

http_requests_total{job="prometheus",group="canary"}

另外，也可以也可以将标签值反向匹配，或者对正则表达式匹配标签值。下面列举匹配操作符：

=：选择正好相等的字符串标签  
!=：选择不相等的字符串标签  
=~：选择匹配正则表达式的标签（或子标签）  
!=：选择不匹配正则表达式的标签（或子标签）  
例如，选择staging、testing、development环境下的，GET之外的HTTP方法的http\_requests\_total的时间序列：

http_requests_total{environment=~"staging|testing|development",method!="GET"}

**范围向量选择**  
范围向量表达式正如即时向量表达式一样运行，但是前者返回从当前时刻开始的一定时间范围的时间序列集合回来。语法是，在一个向量表达式之后添加\[\]来表示时间范围，持续时间用数字表示，后接下面单元之一：

s：seconds  
m：minutes  
h：hours  
d：days  
w：weeks  
y：years  
在下面这个例子中，我们选择最后5分钟的记录，metric名称为http\_requests\_total、作业标签为prometheus的时间序列的所有值：

http_requests_total{job="prometheus"}[5m]

**操作符**  
Prometheus支持多种二元和聚合的操作符。

+ (addition)
    - (subtraction)
    * (multiplication)
    / (division)
    % (modulo)
    ^ (power/exponentiation)
    
    == (equal)
    != (not-equal)
    > (greater-than)
    < (less-than)
    >= (greater-or-equal)
    <= (less-or-equal)
    
    and (intersection)
    or (union)
    unless (complement)

**函数**  
Prometheus支持多种函数，来对数据进行操作，参考官网：https://prometheus.io/docs/prometheus/latest/querying/functions/

了解了metric查询表达式的基础上，下面开始部署告警器组件。

## 二、告警媒介 ##

prometheus支持多种类型的告警媒介，国内可以用的例如mail/webchat，也可以使用webhook自定义接口，公司一般使用的钉钉，prometheus没有定制的钉钉接口，因此在这里使用自定义的接口来中转，将消息发送至钉钉接口，接收钉钉告警消息。  
首先看下告警配置，各项参数已添加中文注释，直接看注释：  
alertmanager-config.yaml:

kind: ConfigMap
    apiVersion: v1
    metadata:
      name: alertmanager
      namespace: kube-system
    data:
      config.yml: |-
        global:
          resolve_timeout: 5m
        templates:
        - '/etc/alertmanager-templates/*.tmpl'
        route:
          group_by: ['alertname', 'cluster', 'service']
    	  #根据['alertname', 'cluster', 'service']，在初始告警发送前，等待30秒，将这段时间的多个告警进行分组
          # When a new group of alerts is created by an incoming alert, wait at
          # least 'group_wait' to send the initial notification.
          # This way ensures that you get multiple alerts for the same group that start
          # firing shortly after another are batched together on the first
          # notification.
    
          group_wait: 30s
    
          # When the first notification was sent, wait 'group_interval' to send a batch
          # of new alerts that started firing for that group.
    	  #按上面分组的消息，同一组消息，间隔5m才发送下一个。这个是为了尽量避免由一个问题带来的批量告警重复发送。
          group_interval: 5m
    
          # If an alert has successfully been sent, wait 'repeat_interval' to
          # resend them.
          #完全相同的一个告警消息，间隔repeat_interval时间才下一次发送，这里为了测试效果设置1m，一般这个值设置时间都较长
          #repeat_interval: 1m
          repeat_interval: 1m
    
          # A default receiver
    
          # If an alert isn't caught by a route, send it to default.
          #默认接收器为webhook_alert 
          receiver: webhook_alert 
    
          # All the above attributes are inherited by all child routes and can
          # overwritten on each.
    
          # The child route trees.
          routes:
          #给webhook_alert接收器定义匹配标签规则
          # Send severity=slack alerts to slack.
          - match:
              severity: info
            receiver: webhook_alert
          - match:
              severity: warning
            receiver: webhook_alert
            
        # 接收器定义，这里是webhook类型，webhook_configs写上自定义api接口的url。
        # 注意，这里的webhook钩子接口是我自己写的接收prometheus告警的接口，api接收到prometheus的消息后会提取信息，通过钉钉的接口发给相应的人员。
        # 也可以使用wechat/mail的接口，配置方式参考官网：https://prometheus.io/docs/alerting/configuration/
        receivers:
        - name: webhook_alert
          webhook_configs:
          - url: 'http://192.168.88.26:8080/api/1.0/utils/alert/?token=ADW82115yn7YEWXCEW88WEW6'
            send_resolved: true

**prometheus通过webhook发送的告警消息样例：**

{ 
    	"receiver":"webhook_alert",
    	"status":"firing",
    	"alerts":[{ 
    		"status":"firing",
    		"labels":{ 
    			"DEVDB":"","alertname":"NodeMemoryUsage-low",
    			"beta_kubernetes_io_arch":"amd64",
    			"beta_kubernetes_io_os":"linux",
    			"instance":"hv001238",
    			"job":"kubernetes-node-exporter","kubernetes_io_hostname":"hv001238","node_role_kubernetes_io_master":"","severity":"info","team":"node"
    		},
    		"annotations":{ 
    			"description":"hv001238: Memory usage is above 80% (current value is: 52.18385396227273",
    			"summary":"hv001238: High Memory usage detected"
    		},
    		"startsAt":"2018-06-23T03:47:10.408935848Z",
    		"endsAt":"0001-01-01T00:00:00Z",
    		"generatorURL":"http://prometheus-785fc5bbf4-ztlrd:9090/graph?g0.expr=%28node_memory_MemTotal_bytes+-+%28node_memory_MemFree_bytes+%2B+node_memory_Buffers_bytes+%2B+node_memory_Cached_bytes%29%29+%2F+node_memory_MemTotal_bytes+%2A+100+%3E+1\\u0026g0.tab=1"
    	},],
    
    	"groupLabels":{ "alertname":"NodeMemoryUsage-low"},
    	"commonLabels":{ 
    		"DEVDB":"",
    		"alertname":"NodeMemoryUsage-low",
    		"beta_kubernetes_io_arch":"amd64",
    		"beta_kubernetes_io_os":"linux",
    		"job":"kubernetes-node-exporter",
    		"node_role_kubernetes_io_master":"",
    		"severity":"info","team":"node"},
    		"commonAnnotations":{ },
    		"externalURL":"http://alertmanager-7cffc68878-xb2m6:9093",
    		"version":"4",
    		"groupKey":"{}/{severity=\\"info\\"}:{alertname=\\"NodeMemoryUsage-low\\"}"
    }

消息太多，不够精简，我webhook端在接收之后将它精简提取为了如下格式：

{ 
    	'description': 'hv001238: Memory usage is above 80% (current value is: 39.42384016274741', 
    	'title': 'hv001238: High Memory usage detected', 
    	'notice_user': ['xxx', 'xxx', 'xxx'], 
    	'start_time': '2018-06-23T03:47:10.408935848Z',
    	'end_time': '0001-01-01T00:00:00Z', 
    	'status': 'firing', 
    	'graph_link': 'http://http://prometheusv19.xxx.com/graph?g0.expr=%28node_memory_MemTotal_bytes+-+%28node_memory_MemFree_bytes+%2B+node_memory_Buffers_bytes+%2B+node_memory_Cached_bytes%29%29+%2F+node_memory_MemTotal_bytes+%2A+100+%3E+1&g0.tab=1'
    }

中转api接口python(django + rest-framework框架)代码样例如下，钉钉消息的接口可以自己去官网查：[钉钉官网][Link 1]

from rest_framework.views import APIView
    from rest_framework.response import Response
    import collections
    
    from account.tasks.message import send_dingding_message
    
    class AlertView(APIView):
    
        def post(self,request):
            token = request.GET.get('token')
            message = collections.OrderedDict()
    
            if token == 'ADW82115yn7YEWXCEW88WEW6xxwetrcX':
                # ops = ['xxx', 'xxx', 'xxx']
                ops = ['xxx']
                content = request.data
                message['title'] = content['alerts'][0]['annotations']['summary']
                message['status'] = content['status']
                message['description'] = content['alerts'][0]['annotations']['description']
                message['start_time'] = content['alerts'][0]['startsAt']
                message['end_time'] = content['alerts'][0]['endsAt']
    			#截图有效的url段，并将hostname从podname替换成自己真实环境的域名，这样接收到的消息点击链接可以直接查看告警数据及图形
                valid_link = content['alerts'][0]['generatorURL'].split("\\")[0]
                uri = valid_link.split(':9090')[1]
                host = "http://prometheus.xxx.com"
                message['graph_link'] = host + uri
    
                messages = ""
                for k,v in message.items():
                    messages = messages + '[' + k + ']:' + v + "\n"
    
                print(messages)
                res = send_dingding_message(user=ops,message=messages)
    
                return Response(res)
    
    def send_dingding_message(user,message)
    	#自己去获取钉钉的api接口，调用接口
        return True

## 三、Alertmanager部署 ##

Alertmanager相关部署yaml文件：

alertmanager-templates.yaml     		#各类常见告警模板
    configmap.yaml                          #配置文件
    deployment.yaml                        #部署文件
    service.yaml                           #服务文件

alertmanager-templates.yaml：

apiVersion: v1
    data:
      default.tmpl: | { { define "__alertmanager" }}AlertManager{ { end }} { { define "__alertmanagerURL" }}{ { .ExternalURL }}/#/alerts?receiver={ { .Receiver }}{ { end }}
    
        { {  define "__subject" }}[{ {  .Status | toUpper }}{ {  if eq .Status "firing" }}:{ {  .Alerts.Firing | len }}{ {  end }}] { {  .GroupLabels.SortedPairs.Values | join " " }} { {  if gt (len .CommonLabels) (len .GroupLabels) }}({ {  with .CommonLabels.Remove .GroupLabels.Names }}{ {  .Values | join " " }}{ {  end }}){ {  end }}{ {  end }}
        { {  define "__description" }}{ {  end }}
    
        { {  define "__text_alert_list" }}{ {  range . }}Labels:
        { {  range .Labels.SortedPairs }} - { {  .Name }} = { {  .Value }}
        { {  end }}Annotations:
        { {  range .Annotations.SortedPairs }} - { {  .Name }} = { {  .Value }}
        { {  end }}Source: { {  .GeneratorURL }}
        { {  end }}{ {  end }}
    
    
        { {  define "slack.default.title" }}{ {  template "__subject" . }}{ {  end }}
        { {  define "slack.default.username" }}{ {  template "__alertmanager" . }}{ {  end }}
        { {  define "slack.default.fallback" }}{ {  template "slack.default.title" . }} | { {  template "slack.default.titlelink" . }}{ {  end }}
        { {  define "slack.default.pretext" }}{ {  end }}
        { {  define "slack.default.titlelink" }}{ {  template "__alertmanagerURL" . }}{ {  end }}
        { {  define "slack.default.iconemoji" }}{ {  end }}
        { {  define "slack.default.iconurl" }}{ {  end }}
        { {  define "slack.default.text" }}{ {  end }}
    
    
        { {  define "hipchat.default.from" }}{ {  template "__alertmanager" . }}{ {  end }}
        { {  define "hipchat.default.message" }}{ {  template "__subject" . }}{ {  end }}
    
    
        { {  define "pagerduty.default.description" }}{ {  template "__subject" . }}{ {  end }}
        { {  define "pagerduty.default.client" }}{ {  template "__alertmanager" . }}{ {  end }}
        { {  define "pagerduty.default.clientURL" }}{ {  template "__alertmanagerURL" . }}{ {  end }}
        { {  define "pagerduty.default.instances" }}{ {  template "__text_alert_list" . }}{ {  end }}
    
    
        { {  define "opsgenie.default.message" }}{ {  template "__subject" . }}{ {  end }}
        { {  define "opsgenie.default.description" }}{ {  .CommonAnnotations.SortedPairs.Values | join " " }}
        { {  if gt (len .Alerts.Firing) 0 -}}
        Alerts Firing:
        { {  template "__text_alert_list" .Alerts.Firing }}
        { { - end }}
        { {  if gt (len .Alerts.Resolved) 0 -}}
        Alerts Resolved:
        { {  template "__text_alert_list" .Alerts.Resolved }}
        { { - end }}
        { { - end }}
        { {  define "opsgenie.default.source" }}{ {  template "__alertmanagerURL" . }}{ {  end }}
    
    
        { {  define "victorops.default.message" }}{ {  template "__subject" . }} | { {  template "__alertmanagerURL" . }}{ {  end }}
        { {  define "victorops.default.from" }}{ {  template "__alertmanager" . }}{ {  end }}
    
    
        { {  define "email.default.subject" }}{ {  template "__subject" . }}{ {  end }}
        { {  define "email.default.html" }}
        <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
         <html xmlns="http://www.w3.org/1999/xhtml" xmlns="http://www.w3.org/1999/xhtml" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;"> <head style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;"> <meta name="viewport" content="width=device-width" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" /> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" /> <title style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">{ { template "__subject" . }}</title>
    
        </head>
    
        <body itemscope="" itemtype="http://schema.org/EmailMessage" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; -webkit-font-smoothing: antialiased; -webkit-text-size-adjust: none; height: 100%; line-height: 1.6em; width: 100% !important; background-color: #f6f6f6; margin: 0; padding: 0;" bgcolor="#f6f6f6">
    
        <table style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; width: 100%; background-color: #f6f6f6; margin: 0;" bgcolor="#f6f6f6">
          <tr style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">
            <td style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; vertical-align: top; margin: 0;" valign="top"></td>
            <td width="600" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; vertical-align: top; display: block !important; max-width: 600px !important; clear: both !important; width: 100% !important; margin: 0 auto; padding: 0;" valign="top">
              <div style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; max-width: 600px; display: block; margin: 0 auto; padding: 0;">
                <table width="100%" cellpadding="0" cellspacing="0" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; border-radius: 3px; background-color: #fff; margin: 0; border: 1px solid #e9e9e9;" bgcolor="#fff">
                  <tr style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">
                    <td style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 16px; vertical-align: top; color: #fff; font-weight: 500; text-align: center; border-radius: 3px 3px 0 0; background-color: #E6522C; margin: 0; padding: 20px;" align="center" bgcolor="#E6522C" valign="top">
                      { {  .Alerts | len }} alert{ {  if gt (len .Alerts) 1 }}s{ {  end }} for { {  range .GroupLabels.SortedPairs }}
                        { {  .Name }}={ {  .Value }}
                      { {  end }}
                    </td>
                  </tr>
                  <tr style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">
                    <td style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; vertical-align: top; margin: 0; padding: 10px;" valign="top">
                      <table width="100%" cellpadding="0" cellspacing="0" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">
                        <tr style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">
                          <td style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; vertical-align: top; margin: 0; padding: 0 0 20px;" valign="top">
                            <a href="{ {  template "__alertmanagerURL" . }}" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; color: #FFF; text-decoration: none; line-height: 2em; font-weight: bold; text-align: center; cursor: pointer; display: inline-block; border-radius: 5px; text-transform: capitalize; background-color: #348eda; margin: 0; border-color: #348eda; border-style: solid; border-width: 10px 20px;">View in { { template "__alertmanager" . }}</a>
                          </td>
                        </tr>
                        { {  if gt (len .Alerts.Firing) 0 }}
                        <tr style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">
                          <td style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; vertical-align: top; margin: 0; padding: 0 0 20px;" valign="top">
                            <strong style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">[{ {  .Alerts.Firing | len }}] Firing</strong>
                          </td>
                        </tr>
                        { {  end }}
                        { {  range .Alerts.Firing }}
                        <tr style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">
                          <td style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; vertical-align: top; margin: 0; padding: 0 0 20px;" valign="top">
                            <strong style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">Labels</strong><br style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />
                            { {  range .Labels.SortedPairs }}{ {  .Name }} = { {  .Value }}<br style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />{ {  end }}
                            { {  if gt (len .Annotations) 0 }}<strong style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">Annotations</strong><br style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />{ {  end }}
                            { {  range .Annotations.SortedPairs }}{ {  .Name }} = { {  .Value }}<br style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />{ {  end }}
                            <a href="{ {  .GeneratorURL }}" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; color: #348eda; text-decoration: underline; margin: 0;">Source</a><br style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />
                          </td>
                        </tr>
                        { {  end }}
    
                        { {  if gt (len .Alerts.Resolved) 0 }}
                          { {  if gt (len .Alerts.Firing) 0 }}
                        <tr style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">
                          <td style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; vertical-align: top; margin: 0; padding: 0 0 20px;" valign="top">
                            <br style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />
                            <hr style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />
                            <br style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />
                          </td>
                        </tr>
                          { {  end }}
                        <tr style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">
                          <td style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; vertical-align: top; margin: 0; padding: 0 0 20px;" valign="top">
                            <strong style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">[{ {  .Alerts.Resolved | len }}] Resolved</strong>
                          </td>
                        </tr>
                        { {  end }}
                        { {  range .Alerts.Resolved }}
                        <tr style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">
                          <td style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; vertical-align: top; margin: 0; padding: 0 0 20px;" valign="top">
                            <strong style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">Labels</strong><br style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />
                            { {  range .Labels.SortedPairs }}{ {  .Name }} = { {  .Value }}<br style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />{ {  end }}
                            { {  if gt (len .Annotations) 0 }}<strong style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">Annotations</strong><br style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />{ {  end }}
                            { {  range .Annotations.SortedPairs }}{ {  .Name }} = { {  .Value }}<br style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />{ {  end }}
                            <a href="{ {  .GeneratorURL }}" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; color: #348eda; text-decoration: underline; margin: 0;">Source</a><br style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;" />
                          </td>
                        </tr>
                        { {  end }}
                      </table>
                    </td>
                  </tr>
                </table>
    
                <div style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; width: 100%; clear: both; color: #999; margin: 0; padding: 20px;">
                  <table width="100%" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">
                    <tr style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; margin: 0;">
                      <td style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 12px; vertical-align: top; text-align: center; color: #999; margin: 0; padding: 0 0 20px;" align="center" valign="top"><a href="{ { .ExternalURL }}" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 12px; color: #999; text-decoration: underline; margin: 0;">Sent by { { template "__alertmanager" . }}</a></td>
                    </tr>
                  </table>
                </div></div>
            </td>
            <td style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 14px; vertical-align: top; margin: 0;" valign="top"></td>
          </tr>
        </table>
    
        </body>
        </html>
    
        { {  end }}
    
        { {  define "pushover.default.title" }}{ {  template "__subject" . }}{ {  end }}
        { {  define "pushover.default.message" }}{ {  .CommonAnnotations.SortedPairs.Values | join " " }}
        { {  if gt (len .Alerts.Firing) 0 }}
        Alerts Firing:
        { {  template "__text_alert_list" .Alerts.Firing }}
        { {  end }}
        { {  if gt (len .Alerts.Resolved) 0 }}
        Alerts Resolved:
        { {  template "__text_alert_list" .Alerts.Resolved }}
        { {  end }}
        { {  end }}
        { {  define "pushover.default.url" }}{ {  template "__alertmanagerURL" . }}{ {  end }}
      slack.tmpl: | { { define "slack.devops.text" }} { {range .Alerts}}{ {.Annotations.DESCRIPTION}} { {end}} { { end }}
    kind: ConfigMap
    metadata:
      creationTimestamp: null
      name: alertmanager-templates
      namespace: kube-system

configmap.yaml：

kind: ConfigMap
    apiVersion: v1
    metadata:
      name: alertmanager
      namespace: kube-system
    data:
      config.yml: |-
        global:
          # ResolveTimeout is the time after which an alert is declared resolved
          # if it has not been updated.
          resolve_timeout: 5m
          # The smarthost and SMTP sender used for mail notifications.
    
          # The API URL to use for Slack notifications.
        # # The directory from which notification templates are read.
        templates:
        - '/etc/alertmanager-templates/*.tmpl'
    
        # The root route on which each incoming alert enters.
        route:
    
          # The labels by which incoming alerts are grouped together. For example,
          # multiple alerts coming in for cluster=A and alertname=LatencyHigh would
          # be batched into a single group.
    
          group_by: ['alertname', 'cluster', 'service']
    
          # When a new group of alerts is created by an incoming alert, wait at
          # least 'group_wait' to send the initial notification.
          # This way ensures that you get multiple alerts for the same group that start
          # firing shortly after another are batched together on the first
          # notification.
    
          group_wait: 30s
    
          # When the first notification was sent, wait 'group_interval' to send a batch
          # of new alerts that started firing for that group.
    
          group_interval: 5m
    
          # If an alert has successfully been sent, wait 'repeat_interval' to
          # resend them.
    
          #repeat_interval: 1m
          repeat_interval: 1m
    
          # A default receiver
    
          # If an alert isn't caught by a route, send it to default.
          receiver: webhook_alert 
    
          # All the above attributes are inherited by all child routes and can
          # overwritten on each.
    
          # The child route trees.
          routes:
          # Send severity=slack alerts to slack.
          - match:
              severity: info
            receiver: webhook_alert
          - match:
              severity: warning
            receiver: webhook_alert
    
        receivers:
        - name: webhook_alert
          webhook_configs:
          - url: 'http://192.168.88.26:8080/api/1.0/utils/alert/?token=ADW82115yn7YEWXCEW88WEW6'
            send_resolved: true

deployment.yaml:

apiVersion: extensions/v1beta1
    kind: Deployment
    metadata:
      name: alertmanager
      namespace: kube-system
    spec:
      replicas: 1
      selector:
        matchLabels:
          app: alertmanager
      template:
        metadata:
          name: alertmanager
          labels:
            app: alertmanager
        spec:
          containers:
          - name: alertmanager
            image: quay.io/prometheus/alertmanager:v0.15.0
            args:
              - '--config.file=/etc/alertmanager/config.yml'
              - '--storage.path=/alertmanager'
            ports:
            - name: alertmanager
              containerPort: 9093
            volumeMounts:
            - name: config-volume
              mountPath: /etc/alertmanager
            - name: templates-volume
              mountPath: /etc/alertmanager-templates
            - name: alertmanager
              mountPath: /alertmanager
          serviceAccountName: prometheus
          volumes:
          - name: config-volume
            configMap:
              name: alertmanager
          - name: templates-volume
            configMap:
              name: alertmanager-templates
          - name: alertmanager
            emptyDir: { }

service.yaml:

apiVersion: v1
    kind: Service
    metadata:
      annotations:
        prometheus.io/scrape: 'true'
        prometheus.io/path: '/metrics'
      labels:
        name: alertmanager
      name: alertmanager
      namespace: kube-system
    spec:
      selector:
        app: alertmanager
      type: NodePort
      ports:
      - name: alertmanager
        protocol: TCP
        port: 9093
        targetPort: 9093

依次部署上方几个yaml文件。  
在配置完alertmanager之后，需要给prometheus主程序配置文件添加alertmanager相关的配置，即修改prometheus的configmap，添加data.rules.yml，增加一些达到触发告警阈值的规则。

rules.yml: | groups: - name: test-rule rules: - alert: NodeFilesystemUsage-high expr: (node_filesystem_size{device="rootfs"} - node_filesystem_free{device="rootfs"}) / node_filesystem_size{device="rootfs"} * 100 > 80 for: 2m labels: team: node severity: warning annotations: summary: "{ {$labels.instance}}: High Filesystem usage detected" description: "{ {$labels.instance}}: Filesystem usage is above 80% (current value is: { { $value }}" - alert: NodeMemoryUsage expr: (node_memory_MemTotal - (node_memory_MemFree+node_memory_Buffers+node_memory_Cached )) / node_memory_MemTotal * 100 > 80 for: 2m labels: team: node annotations: summary: "{ {$labels.instance}}: High Memory usage detected" description: "{ {$labels.instance}}: Memory usage is above 80% (current value is: { { $value }}" - alert: NodeMemoryUsage-low expr: (node_memory_MemTotal_bytes - (node_memory_MemFree_bytes + node_memory_Buffers_bytes + node_memory_Cached_bytes)) / node_memory_MemTotal_bytes * 100 > 1 for: 1m labels: team: node severity: info annotations: summary: "{ {$labels.instance}}: High Memory usage detected" description: "{ {$labels.instance}}: Memory usage is above 80% (current value is: { { $value }}" - alert: NodeCPUUsage expr: (100 - (avg by (instance) (irate(node_cpu{job="kubernetes-node-exporter",mode="idle"}[5m])) * 100)) > 80 for: 2m labels: team: node annotations: summary: "{ {$labels.instance}}: High CPU usage detected" description: "{ {$labels.instance}}: CPU usage is above 80% (current value is: { { $value }}" - alert: PodMemUsage expr: container_memory_working_set_bytes{pod_name!="",namespace="default"}/container_spec_memory_limit_bytes{pod_name!="",namespace="default"} *100 != +Inf > 10 for: 2m labels: team: node annotations: summary: "{ {$labels.instance}}: Pod High Mem usage detected" description: "{ {$labels.instance}}: Pod CPU Mem is above 80% (current value is: { { $value }}"

更新之后的prometheus的configmap完整yaml文件如下：

kind: ConfigMap
    metadata:
      name: prometheus-config
      namespace: kube-system
    data:
      prometheus.yml: | global: scrape_interval: 15s evaluation_interval: 15s rule_files: - /etc/prometheus/rules.yml alerting: alertmanagers: - static_configs: - targets: ["alertmanager:9093"] 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
            regex: (.+)
          - source_labels: [__address__, __meta_kubernetes_pod_annotation_prometheus_io_port]
            action: replace
            regex: ([^:]+)(?::\d+)?;(\d+)
            replacement: $1:$2
            target_label: __address__
          - action: labelmap
            regex: __meta_kubernetes_pod_label_(.+)
          - source_labels: [__meta_kubernetes_namespace]
            action: replace
            target_label: kubernetes_namespace
          - source_labels: [__meta_kubernetes_pod_name]
            action: replace
            target_label: kubernetes_pod_name
        - job_name: 'kubernetes-node-exporter'
          scheme: http
          tls_config:
            ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
          bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
          kubernetes_sd_configs:
          - role: node
          relabel_configs:
          - action: labelmap
            regex: __meta_kubernetes_node_label_(.+)
          - source_labels: [__meta_kubernetes_role]
            action: replace
            target_label: kubernetes_role
          - source_labels: [__address__]
            regex: '(.*):10250'
            replacement: '${1}:31672'
            target_label: __address__
      rules.yml: | groups: - name: test-rule rules: - alert: NodeFilesystemUsage-high expr: (node_filesystem_size{device="rootfs"} - node_filesystem_free{device="rootfs"}) / node_filesystem_size{device="rootfs"} * 100 > 80 for: 2m labels: team: node severity: warning annotations: summary: "{ {$labels.instance}}: High Filesystem usage detected" description: "{ {$labels.instance}}: Filesystem usage is above 80% (current value is: { { $value }}" - alert: NodeMemoryUsage expr: (node_memory_MemTotal - (node_memory_MemFree+node_memory_Buffers+node_memory_Cached )) / node_memory_MemTotal * 100 > 80 for: 2m labels: team: node annotations: summary: "{ {$labels.instance}}: High Memory usage detected" description: "{ {$labels.instance}}: Memory usage is above 80% (current value is: { { $value }}" - alert: NodeMemoryUsage-low expr: (node_memory_MemTotal_bytes - (node_memory_MemFree_bytes + node_memory_Buffers_bytes + node_memory_Cached_bytes)) / node_memory_MemTotal_bytes * 100 > 1 for: 1m labels: team: node severity: info annotations: summary: "{ {$labels.instance}}: High Memory usage detected" description: "{ {$labels.instance}}: Memory usage is above 80% (current value is: { { $value }}" - alert: NodeCPUUsage expr: (100 - (avg by (instance) (irate(node_cpu{job="kubernetes-node-exporter",mode="idle"}[5m])) * 100)) > 80 for: 2m labels: team: node annotations: summary: "{ {$labels.instance}}: High CPU usage detected" description: "{ {$labels.instance}}: CPU usage is above 80% (current value is: { { $value }}" - alert: PodMemUsage expr: container_memory_working_set_bytes{pod_name!="",namespace="default"}/container_spec_memory_limit_bytes{pod_name!="",namespace="default"} *100 != +Inf > 80 for: 2m labels: team: node annotations: summary: "{ {$labels.instance}}: Pod High Mem usage detected" description: "{ {$labels.instance}}: Pod CPU Mem is above 80% (current value is: { { $value }}"

**为了测试使用，增加了一项node内存使用率超过1%则触发告警，这个在使用时可以删掉。**

**kubectl apply -f config.map更新prometheus配置文件，更新配置文件后，prometheus不会自动重载配置，需重启pod，为了优雅地重载，可以采取更新deployment注解的方式来触发滚动升级，保证服务不中断。使用如下命令：**

kubectl patch deployment prometheus --patch '{"spec": {"template": {"metadata": {"annotations": {"update-time": "2018-06-25 17:50" }}}}}' -n kube-system

#### 特别说明 ####

一般用于容器计算内存使用量的，有两个常用指标：

*  **container\_memory\_usage\_bytes** = container\_memory\_rss + container\_memory\_cache + kernel memory
 *  **container\_memory\_working\_set\_bytes** = container\_memory\_usage\_bytes – total\_inactive\_file（未激活的匿名缓存页）

其中`container_memory_working_set_bytes`是容器真实使用的内存量，也是limit限制时的 oom 判断依据，kubectl top 命令采集的也是这个metric，因此，若你存在容器实际使用内存情况计算不准的情况，可以检查一下是不是混用了这两个metric，建议使用以`container_memory_working_set_bytes`来计算容器的内存使用情况。

## 四、告警效果 ##

查看prometheus告警模块，可以看到激活的告警消息：  
![这里写图片描述][70]

钉钉收到告警消息：  
![这里写图片描述][70 1]  
![这里写图片描述][70 2]

告警处于firing激活状态时，只有有效的start\_time，endtime为无效值，状态为resolved时会有准确的end-time。

点击告警消息中的链接，查看明细数据：  
![这里写图片描述][70 3]  
![这里写图片描述][70 4]

## 总结 ##

配置告警消息并不难，难点在于各项键控值的定义，metrics类型有很多，同时支持的各类应用也有很多，还有很多可摸索的空间。后期还要不断的扩充、调整监控类型，调整优化通知策略，prometheus非常地灵活，可以基于此不断发掘，打造最适合自己公司环境的容器云监控体系。

[k8s_Prometheus]: https://blog.csdn.net/ywq935/article/details/80818390
[Link 1]: https://open-doc.dingtalk.com/docs/doc.htm?spm=a219a.7629140.0.0.HyEbQ7&treeId=367&articleId=107549&docType=1
[70]: /images/20220521/fab8607ee2eb4bcca8756c08f8b3c279.png
[70 1]: /images/20220521/b7e8d48a615f4b9b9d7c497e4d8e208d.png
[70 2]: /images/20220521/f80b1f378d824c6487ce3bbe93e4fcc9.png
[70 3]: /images/20220521/9db71c4c26184bd49dc6dc509394d9d9.png
[70 4]: /images/20220521/a91445cb196847ca86877426741628c2.png