skywalking告警篇详细分析
https://www.cnblogs.com/ssgeek/p/14586397.html
SkyWalking链路追踪系统-告警篇
1、概述
Skywalking
发送告警的基本原理是每隔一段时间轮询skywalking-oap
收集到的链路追踪的数据,再根据所配置的告警规则(如服务响应时间、服务响应时间百分比)等,如果达到阈值则发送响应的告警信息。 发送告警信息是以线程池异步的方式调用webhook
接口完成的,具体的webhook
接口可以由使用者自行定义,从而可以在指定的webhook
接口中自行编写各种告警方式,比如钉钉告警、邮件告警等等。告警的信息也可以在RocketBot
即ui
中查看到。
目前对应我前面文章中部署的8.4.0
版本支持的告警接口如下:
- 普通webhook
- gRPCHook
- Slack Chat Hook
- WeChat Hook(微信告警)
- Dingtalk Hook(钉钉告警)
- Feishu Hook(飞书告警)
2、告警规则
2.1 默认告警规则
在Skywalking
中,告警规则称为rule
,默认安装的Skywalking
oap server
组件中包含了告警规则的配置文件,位于安装目录下config
文件夹下alarm-settings.yml
文件中,在容器中运行的也是一样的
# kubectl -n monitoring exec -it skywalking-oap-57d7f454f5-w4k4j -- bash
bash-5.0# pwd
/skywalking
bash-5.0# cat config/alarm-settings.yml
以下是默认的告警规则配置文件内容
rules:
# Rule unique name, must be ended with `_rule`.
service_resp_time_rule:
metrics-name: service_resp_time
op: ">"
threshold: 1000
period: 10
count: 3
silence-period: 5
message: Response time of service {name} is more than 1000ms in 3 minutes of last 10 minutes.
service_sla_rule:
# Metrics value need to be long, double or int
metrics-name: service_sla
op: "<"
threshold: 8000
# The length of time to evaluate the metrics
period: 10
# How many times after the metrics match the condition, will trigger alarm
count: 2
# How many times of checks, the alarm keeps silence after alarm triggered, default as same as period.
silence-period: 3
message: Successful rate of service {name} is lower than 80% in 2 minutes of last 10 minutes
service_resp_time_percentile_rule:
# Metrics value need to be long, double or int
metrics-name: service_percentile
op: ">"
threshold: 1000,1000,1000,1000,1000
period: 10
count: 3
silence-period: 5
message: Percentile response time of service {name} alarm in 3 minutes of last 10 minutes, due to more than one condition of p50 > 1000, p75 > 1000, p90 > 1000, p95 > 1000, p99 > 1000
service_instance_resp_time_rule:
metrics-name: service_instance_resp_time
op: ">"
threshold: 1000
period: 10
count: 2
silence-period: 5
message: Response time of service instance {name} is more than 1000ms in 2 minutes of last 10 minutes
database_access_resp_time_rule:
metrics-name: database_access_resp_time
threshold: 1000
op: ">"
period: 10
count: 2
message: Response time of database access {name} is more than 1000ms in 2 minutes of last 10 minutes
endpoint_relation_resp_time_rule:
metrics-name: endpoint_relation_resp_time
threshold: 1000
op: ">"
period: 10
count: 2
message: Response time of endpoint relation {name} is more than 1000ms in 2 minutes of last 10 minutes
# Active endpoint related metrics alarm will cost more memory than service and service instance metrics alarm.
# Because the number of endpoint is much more than service and instance.
#
# endpoint_avg_rule:
# metrics-name: endpoint_avg
# op: ">"
# threshold: 1000
# period: 10
# count: 2
# silence-period: 5
# message: Response time of endpoint {name} is more than 1000ms in 2 minutes of last 10 minutes
webhooks:
# - http://127.0.0.1/notify/
# - http://127.0.0.1/go-wechat/
2.2 告警规则详解
下面取默认的告警规则中的一条进行分析
rules:
# Rule unique name, must be ended with `_rule`.
service_resp_time_rule:
metrics-name: service_resp_time
op: ">"
threshold: 1000
period: 10
count: 3
silence-period: 5
message: Response time of service {name} is more than 1000ms in 3 minutes of last 10 minutes.
首先提示声明了告警规则名称应该具有唯一性,且必须以 _rule
结尾,这里是service_resp_time_rule
(服务响应时间)
-
metrics-name:告警指标,指标度量值为
long
、double
或int
类型 -
op:度量值和阈值的比较方式,这里是大于
-
threshold:阈值,这里是
1000
,毫秒为单位 -
period:评估度量标准的时间长度,也就是告警检查周期,分钟为单位
-
count:累计达到多少次告警值后触发告警
-
silence-period:忽略相同告警信息的周期,默认与告警检查周期一致。简单来说,就是在触发告警时开始计时
N
,在N
+period
时间内保持沉默silence
不会再次触发告警,这和alertmanager
的告警抑制类似 -
message:告警消息主体,通过变量在发送消息时进行自动替换
除此之外,还有以下可选(高级)规则配置:
-
排除或包含服务配置,默认匹配此指标中的所有服务
... service_percent_rule: metrics-name: service_percent include-names: - service_a - service_b exclude-names: - service_c ...
-
多种值情况的指标阈值,例如P50、P75、P90、P95、P99的阈值,主要表示样本的分布及其数量,例如
P50
表示取值周期内有50%
的响应都大于1000ms
,这和prometheus
聚合指标quantile
是一样的,如果同时写表示都满足时触发例如下面的规则表示在过去
10
分钟内,由于p50 > 1000、p75 > 1000、p90 > 1000、p95 > 1000、p99 > 1000多个条件,服务累计3
次的响应时间百分比都大于1000ms
,触发告警... service_resp_time_percentile_rule: # Metrics value need to be long, double or int metrics-name: service_percentile op: ">" threshold: 1000,1000,1000,1000,1000 period: 10 count: 3 silence-period: 5 message: Percentile response time of service {name} alarm in 3 minutes of last 10 minutes, due to more than one condition of p50 > 1000, p75 > 1000, p90 > 1000, p95 > 1000, p99 > 1000
-
复合规则composite-rules,针对相同实体级别而言的规则,例如服务级别的警报规则,同时满足指定的多个规则时触发
rules: endpoint_percent_rule: # Metrics value need to be long, double or int metrics-name: endpoint_percent ... # Specify if the rule can send notification or just as an condition of composite rule 仅作为复合规则的条件 only-as-condition: false service_percent_rule: metrics-name: service_percent ... only-as-condition: false service_resp_time_percentile_rule: # Metrics value need to be long, double or int metrics-name: service_percentile ... only-as-condition: false meter_service_status_code_rule: metrics-name: meter_status_code ... only-as-condition: false composite-rules: comp_rule: # Must satisfied percent rule and resp time rule expression: service_percent_rule && service_resp_time_percentile_rule message: Service {name} successful rate is less than 80% and P50 of response time is over 1000ms # 服务成功率小于80%,响应时间大于1000ms
到这里,就能分析出上面列出的所有默认告警规则的含义,依次为:
1 最近3分钟内服务平均响应时间超过1秒
2 最近2分钟内服务成功率低于80%
3 最近3分钟的服务响应时间百分比超过1秒
4 最近2分钟内服务实例的平均响应时间超过1秒
5 最近2分钟内数据库访问的平均响应时间超过1秒
6 最近2分钟内端点平均响应时间超过1秒
7 过去2分钟内端点关系的平均响应时间超过1秒
这条规则默认没有打开,并且提示:由于端点的数量远远多于服务和实例,活动端点相关度量告警将比服务和服务实例度量告警消耗更多内存
3、自定义告警规则
Skywalking
的配置大部分内容是通过应用的application.yml
及系统的环境变量设置的,同时也支持下面系统的动态配置来源
- gRPC服务
- Zookeeper
- Etcd
- Consul
- Apollo
- Nacos
- k8s configmap
参考Skywalking
动态配置说明,如果开启了动态配置,可以通过键alarm.default.alarm-settings
覆盖掉默认配置文件alarm-settings.yml
本文记录的是基于k8s
和helm
部署的Skywalking
,因此可以通过k8s-configmap
进行自定义配置的注入,最终在Skywalking
配置文件中的实现如下,此文件中有很多变量,通过分析chart
,发现已经写好逻辑会根据是否启用动态配置来自动注入所有变量,所以就无需在value.yaml
中声明了
cluster:
selector: ${SW_CLUSTER:standalone}
...
kubernetes:
namespace: ${SW_CLUSTER_K8S_NAMESPACE:default}
labelSelector: ${SW_CLUSTER_K8S_LABEL:app=collector,release=skywalking}
uidEnvName: ${SW_CLUSTER_K8S_UID:SKYWALKING_COLLECTOR_UID}
...
configuration:
selector: ${SW_CONFIGURATION:k8s-configmap}
...
k8s-configmap:
# Sync period in seconds. Defaults to 60 seconds.
period: ${SW_CONFIG_CONFIGMAP_PERIOD:60}
# Which namespace is confiigmap deployed in.
namespace: ${SW_CLUSTER_K8S_NAMESPACE:default}
# Labelselector is used to locate specific configmap
labelSelector: ${SW_CLUSTER_K8S_LABEL:app=collector,release=skywalking}
在自定义配置告警规则的同时加入webhook
后端报警相关配置,configmap
文件写法可以参考官方helm configmap示例
我这里只把默认的报警规则提示信息改成了中文报警信息,具体每条规则的参数没有变化,同时还加入了钉钉webhook
配置,具体流程如下
修改chart
包的value.yaml
,开启动态配置
...
oap:
name: oap
dynamicConfigEnabled: true # 开启动态配置功能
...
修改chart
包中template
的oap-configmap.yaml
,配置自定义的rule
和钉钉webhook
{{- if .Values.oap.dynamicConfigEnabled }}
apiVersion: v1
kind: ConfigMap
metadata:
name: skywalking-dynamic-config
labels:
app: {{ template "skywalking.name" . }}
release: {{ .Release.Name }}
component: {{ .Values.oap.name }}
data:
alarm.default.alarm-settings: |-
rules:
# Rule unique name, must be ended with `_rule`.
service_resp_time_rule:
metrics-name: service_resp_time
op: ">"
threshold: 1000
period: 10
count: 3
silence-period: 5
message: 最近3分钟内服务 {name} 的平均响应时间超过1秒
service_sla_rule:
# Metrics value need to be long, double or int
metrics-name: service_sla
op: "<"
threshold: 8000
# The length of time to evaluate the metrics
period: 10
# How many times after the metrics match the condition, will trigger alarm
count: 2
# How many times of checks, the alarm keeps silence after alarm triggered, default as same as period.
silence-period: 3
message: 最近2分钟内服务 {name} 的成功率低于80%
service_resp_time_percentile_rule:
# Metrics value need to be long, double or int
metrics-name: service_percentile
op: ">"
threshold: 1000,1000,1000,1000,1000
period: 10
count: 3
silence-period: 5
message: 最近3分钟的服务 {name} 的响应时间百分比超过1秒
service_instance_resp_time_rule:
metrics-name: service_instance_resp_time
op: ">"
threshold: 1000
period: 10
count: 2
silence-period: 5
message: 最近2分钟内服务实例 {name} 的平均响应时间超过1秒
database_access_resp_time_rule:
metrics-name: database_access_resp_time
threshold: 1000
op: ">"
period: 10
count: 2
# message: Response time of database access {name} is more than 1000ms in 2 minutes of last 10 minutes
message: 最近2分钟内数据库访问 {name} 的平均响应时间超过1秒
endpoint_relation_resp_time_rule:
metrics-name: endpoint_relation_resp_time
threshold: 1000
op: ">"
period: 10
count: 2
message: 最近2分钟内端点 {name} 的平均响应时间超过1秒
dingtalkHooks:
textTemplate: |-
{
"msgtype": "text",
"text": {
"content": "SkyWalking 链路追踪告警: \n %s."
}
}
webhooks:
- url: https://oapi.dingtalk.com/robot/send?access_token=<钉钉机器人token>
secret: <钉钉机器人加签>
{{- end }}
修改完成后,执行helm
进行更新
# ls
skywalking
# helm -n monitoring upgrade skywalking skywalking --values ./skywalking/values.yaml
# helm -n monitoring list
NAME NAMESPACE REVISION UPDATED STATUS CHART APP VERSION
skywalking monitoring 3 2021-03-22 13:35:36.779541 +0800 CST deployed skywalking-4.0.0
# helm -n monitoring history skywalking
REVISION UPDATED STATUS CHART APP VERSION DESCRIPTION
1 Sun Mar 21 17:45:34 2021 superseded skywalking-4.0.0 Install complete
2 Mon Mar 22 13:35:36 2021 deployed skywalking-4.0.0 Upgrade complete
观察pod状态,直到正常
# kubectl -n monitoring get pods
NAME READY STATUS RESTARTS AGE
elasticsearch-logging-0 1/1 Running 0 19h
elasticsearch-logging-1 1/1 Running 0 19h
elasticsearch-logging-2 1/1 Running 0 19h
skywalking-es-init-ktdcn 0/1 Completed 0 19h
skywalking-oap-7bbb775965-49895 1/1 Running 0 15s
skywalking-oap-7bbb775965-s89dz 1/1 Running 0 43s
skywalking-ui-698cdb4dbc-mjl2m 1/1 Running 0 19h
4、测试告警
为了测试告警功能,拉上业务研发在项目中简单写了个url
地址,请求时会超时5s
返回
然后利用浏览器或postman
请求应用的/api/timeout
进行测试
查看Skywalking
的ui
界面,链路追踪
告警界面
到钉钉中查看报警消息
到这里,在Skywalking
中配置报警就完成了 ~
附:在一次Skywalking
线上分享会上记录的关于使用Skywalking
定位问题的思路:
- 纵览全局,
Skywalking
拓扑图 - 监控告警,
metric
/tracing
确定问题存在故障(根据metric
做告警,根据tracing
统计作比较) - 确定故障在哪,
tracing
调用关系,确定故障出现在哪个service
或者endpoint
profile
手段(skywalking
新能力)或者常见传统性能定位方法,定位单节点问题所在(比如CPU
、内存、io
、网络 ——> 动态追踪采样 ——> 火焰图)基本可以解决99.9%的问题
posted on 2022-03-20 21:12 luzhouxiaoshuai 阅读(497) 评论(0) 编辑 收藏 举报