SkyWalking 链路数据接入最佳实践

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简介

微服务架构下，一个请求会涉及多个服务，一个服务也可能依赖其它服务，这样一个请求下来就构成了一个调用链。如果服务部署成高可用，就会有多个节点。如果其中一个节点出现异常，整个请求就会受到到影响，在这种情况下就需要一个工具来帮助我们分析问题、定位问题和解决问题。
Skywalking 是一个开源的可观察性平台，用于收集、分析、聚合和可视化来自服务和云原生基础设施的数据。Skywalking 提供了基于分布式跟踪的应用程序性能监控系统的解决方案，支持 Java、C#、Node.js、Go、PHP 等。

DataKit 只需开启 Skywalking Input，即可采集 Skywalking Agent上报来的链路数据。

前置条件

安装 DataKit

• <安装 DataKit>

本文datakit版本1.4.17，skywalking agent版本为v8.6.0。

数据接入

开启 Input

1、 开启 SkyWalking 插件，复制 Sample 文件

cd /usr/local/datakit/conf.d/skywalking
cp skywalking.conf.sample skywalking.conf

2、 修改 skywalking.conf 文件

[[inputs.skywalking]]
  ## Skywalking grpc server listening on address.
  address = "localhost:11800"

  ## plugins is a list contains all the widgets used in program that want to be regarded as service.
  ## every key words list in plugins represents a plugin defined as special tag by skywalking.
  ## the value of the key word will be used to set the service name.
  # plugins = ["db.type"]

  ## customer_tags is a list of keys contains keys set by client code like span.SetTag(key, value)
  ## that want to send to data center. Those keys set by client code will take precedence over
  ## keys in [inputs.skywalking.tags]. DOT(.) IN KEY WILL BE REPLACED BY DASH(_) WHEN SENDING.
  # customer_tags = ["key1", "key2", ...]

  ## Keep rare tracing resources list switch.
  ## If some resources are rare enough(not presend in 1 hour), those resource will always send
  ## to data center and do not consider samplers and filters.
  # keep_rare_resource = false

  ## Ignore tracing resources map like service:[resources...].
  ## The service name is the full service name in current application.
  ## The resource list is regular expressions uses to block resource names.
  ## If you want to block some resources universally under all services, you can set the
  ## service name as "*". Note: double quotes "" cannot be omitted.
  # [inputs.skywalking.close_resource]
    # service1 = ["resource1", "resource2", ...]
    # service2 = ["resource1", "resource2", ...]
    # "*" = ["close_resource_under_all_services"]
    # ...

  ## Sampler config uses to set global sampling strategy.
  ## sampling_rate used to set global sampling rate.
  # [inputs.skywalking.sampler]
    # sampling_rate = 1.0

  # [inputs.skywalking.tags]
    # key1 = "value1"
    # key2 = "value2"
    # ...

  ## Storage config a local storage space in hard dirver to cache trace data.
  ## path is the local file path used to cache data.
  ## capacity is total space size(MB) used to store data.
  # [inputs.skywalking.storage]
    # path = "./skywalking_storage"
    # capacity = 5120

参数说明

• address：接收 skywalking 链路数据的地址

3、 重启 DataKit

systemctl restart datakit

Java 链路数据接入

下载 Skywalking Java Agent

1、 下载 - skywalking-java agent 下载

注意： skywalking agent v8.8.3 目前存在不兼容问题无法使用。目前已支持 v8.5.0 v8.6.0 v8.7.0

2、 解压

tar -zxvf /usr/local/java/apache-skywalking-apm-8.6.0.tar.gz 

3、 复制插件

本示例使用了 Spring Cloud Gateway，由于 Gateway 是基于 Webflux 实现的，必须把 skywalking-agent/optional-plugins/ 目录下的 apm-spring-cloud-gateway-2.1.x-plugin-8.6.0.jar 和 apm-spring-webflux-5.x-plugin-8.6.0.jar 复制到 skywalking-agent/plugins/ 目录下。

cp /usr/local/java/skywalking-agent/optional-plugins/apm-spring-cloud-gateway-2.1.x-plugin-8.6.0.jar /usr/local/java/skywalking-agent/plugins/
cp /usr/local/java/skywalking-agent/optional-plugins/apm-spring-webflux-5.x-plugin-8.6.0.jar /usr/local/java/skywalking-agent/plugins/

启动 Java 应用

本示例部署 3 个微服务，pay、orde 和 gateway。

java -javaagent:/usr/local/java/skywalking-agent/skywalking-agent.jar \
-Dskywalking.agent.service_name=skywalking-pay   \
-Dskywalking.collector.backend_service=localhost:11800  \
-jar cloud-service-pay-1.0-SNAPSHOT.jar 

java -javaagent:/usr/local/java/skywalking-agent/skywalking-agent.jar \
-Dskywalking.agent.service_name=skywalking-order   \
-Dskywalking.collector.backend_service=localhost:11800  \
-jar cloud-service-order-1.0-SNAPSHOT.jar

java -javaagent:/usr/local/java/skywalking-agent/skywalking-agent.jar \
-Dskywalking.agent.service_name=skywalking-gateway   \
-Dskywalking.collector.backend_service=localhost:11800  \
-jar   gateway-1.0-SNAPSHOT.jar

参数说明

• Dskywalking.agent.service_name：微服务别名

• Dskywalking.collector.backend_service：链路数据上报地址

链路数据

前往<观测云>，进入应用性能监测。

• 服务

• 拓扑图

• 火焰图