一、背景
假如我有2种类型的服务器，一种是本地电脑(每个指标名称都存在{nodename='mac-local'})，一种是阿里云服务器(每个指标名称都存在{nodename='aliyun'})，同时每个指标下都存在一个 {instance='具体的服务器的ip地址'}标签。
即咱们采集的工夫序列大抵上都有如下标签：
eg:node_uname_info{nodename='xxxx',instance='yyyy'}
二、需要
咱们想监控一下每台主机的cpu的应用状况。同时不能在一个图形上显示出所有的机器的cpu使用率，须要依据用户的抉择而显示。即要呈现下图所示的后果，这个状况咱们能够通过grafana的模板变量来实现。
从上图能够，instance的呈现是依据 服务器类型 的抉择而不同的。
三、实现步骤
1、创立一个Dashboard
2、设置模板变量
1、在Dashboard页面点击小齿轮⚙️图标。
2、点击创立一个变量
1、增加 nodename 变量，获取服务器的类型
2、增加 instance 变量。
留神：instance变量的值是依据上一步 nodename 变量的值而来的，及抉择不同的 nodename，instance 的值应该是不同的。及在 instance 变量的查问语句中须要援用 nodename 变的值，通过 $nodename 即可援用。
做完上方呈现的1，2两步，即可呈现需要中呈现的画面。
3、创立一个图表，监控一下 cpu 的使用率
四、上方例子的实现json字符串
在 grafana 中引入此json串，即可实现上图的成果。然而要保障每个工夫序列都存在 nodename 和 instance的标签。
{ "annotations": { "list": [ { "builtIn": 1, "datasource": "-- Grafana --", "enable": true, "hide": true, "iconColor": "rgba(0, 211, 255, 1)", "name": "Annotations & Alerts", "type": "dashboard" } ] }, "editable": true, "gnetId": null, "graphTooltip": 0, "id": 3, "iteration": 1616217012533, "links": [], "panels": [ { "aliasColors": {}, "bars": false, "dashLength": 10, "dashes": false, "datasource": null, "decimals": 2, "description": "", "fieldConfig": { "defaults": { "custom": {}, "unit": "percent" }, "overrides": [] }, "fill": 1, "fillGradient": 0, "gridPos": { "h": 8, "w": 24, "x": 0, "y": 0 }, "hiddenSeries": false, "id": 2, "legend": { "alignAsTable": true, "avg": true, "current": true, "max": true, "min": true, "rightSide": true, "show": true, "total": false, "values": true }, "lines": true, "linewidth": 1, "nullPointMode": "null", "options": { "alertThreshold": true }, "percentage": false, "pluginVersion": "7.4.3", "pointradius": 2, "points": true, "renderer": "flot", "seriesOverrides": [], "spaceLength": 10, "stack": false, "steppedLine": false, "targets": [ { "expr": "(1 - avg(irate(node_cpu_seconds_total{mode='idle',nodename=~\"$nodename\",instance=~\"$instance\"}[5m])) by (instance)) * 100", "interval": "", "legendFormat": "{{instance}} CPU使用率", "refId": "A" } ], "thresholds": [], "timeFrom": null, "timeRegions": [], "timeShift": null, "title": "$instance CPU使用率", "tooltip": { "shared": true, "sort": 0, "value_type": "individual" }, "type": "graph", "xaxis": { "buckets": null, "mode": "time", "name": null, "show": true, "values": [] }, "yaxes": [ { "$$hashKey": "object:231", "format": "percent", "label": null, "logBase": 1, "max": null, "min": null, "show": true }, { "$$hashKey": "object:232", "format": "short", "label": null, "logBase": 1, "max": null, "min": null, "show": true } ], "yaxis": { "align": false, "alignLevel": null } } ], "schemaVersion": 27, "style": "dark", "tags": [], "templating": { "list": [ { "allValue": null, "current": { "selected": true, "tags": [], "text": [ "mac-local" ], "value": [ "mac-local" ] }, "datasource": null, "definition": "label_values(node_uname_info{nodename=~\".*\"},nodename)", "description": null, "error": null, "hide": 0, "includeAll": false, "label": "服务器类型", "multi": true, "name": "nodename", "options": [ { "selected": false, "text": "aliyun", "value": "aliyun" }, { "selected": true, "text": "mac-local", "value": "mac-local" } ], "query": { "query": "label_values(node_uname_info{nodename=~\".*\"},nodename)", "refId": "StandardVariableQuery" }, "refresh": 0, "regex": "", "skipUrlSync": false, "sort": 0, "tagValuesQuery": "", "tags": [], "tagsQuery": "", "type": "query", "useTags": false }, { "allValue": null, "current": { "selected": true, "text": [ "localhost:9081" ], "value": [ "localhost:9081" ] }, "datasource": null, "definition": "label_values(node_uname_info{nodename=~\"$nodename\",instance=~\".*\"},instance)", "description": null, "error": null, "hide": 0, "includeAll": false, "label": null, "multi": true, "name": "instance", "options": [ { "selected": true, "text": "localhost:9081", "value": "localhost:9081" } ], "query": { "query": "label_values(node_uname_info{nodename=~\"$nodename\",instance=~\".*\"},instance)", "refId": "StandardVariableQuery" }, "refresh": 0, "regex": "", "skipUrlSync": false, "sort": 0, "tagValuesQuery": "", "tags": [], "tagsQuery": "", "type": "query", "useTags": false } ] }, "time": { "from": "now-5m", "to": "now" }, "timepicker": {}, "timezone": "", "title": "测试模板变量", "uid": "Umb3YDQMz", "version": 6}五、参考链接
1、grafana模板变量的应用