Chaos Mesh 最后作为开源分布式数据库 TiDB 的测试平台而创立，是一个多功能混沌工程平台，通过混沌测试验证分布式系统的稳定性。本文以万里平安数据库软件 GreatDB 分布式部署模式为例，介绍了通过 Chaos Mesh 进行混沌测试的全流程。
1. 需要背景与万里平安数据库软件 GreatDB 分布式部署模式介绍
1.1 需要背景
混沌测试是检测分布式系统不确定性、建设零碎弹性信念的一种十分好的形式，因而咱们采纳开源工具 Chaos Mesh 来做 GreatDB 分布式集群的混沌测试。
1.2 万里平安数据库软件 GreatDB 分布式部署模式介绍
万里平安数据库软件 GreatDB 是一款关系型数据库软件，同时反对集中式和分布式的部署形式，本文波及的是分布式部署形式。
分布式部署模式采纳 shared-nothing 架构；通过数据冗余与正本治理确保数据库无单点故障；数据 sharding 与分布式并行计算实现数据库系统高性能；可无限度动静扩大数据节点，满足业务须要。
整体架构如下图所示：
2. 环境筹备
2.1 Chaos Mesh 装置
在装置 Chaos Mesh 之前请确保曾经事后装置了 helm，docker，并筹备好了一个 kubernetes 环境。
- 应用 Helm 装置
1）在 Helm 仓库中增加 Chaos Mesh 仓库：
helm repo add chaos-mesh https://charts.chaos-mesh.org2）查看能够装置的 Chaos Mesh 版本：
helm search repo chaos-mesh3）创立装置 Chaos Mesh 的命名空间：
kubectl create ns chaos-testing4）在 docker 环境下装置 Chaos Mesh：
helm install chaos-mesh chaos-mesh/chaos-mesh -n=chaos-testing- 验证装置
执行以下命令查看 Chaos Mesh 的运行状况：
kubectl get pod -n chaos-testing
上面是预期输入：
NAME READY STATUS RESTARTS AGEchaos-controller-manager-d7bc9ccb5-dbccq 1/1 Running 0 26dchaos-daemon-pzxc7 1/1 Running 0 26dchaos-dashboard-5887f7559b-kgz46 1/1 Running 1 26d如果 3 个 pod 的状态都是 Running，示意 Chaos Mesh 曾经胜利装置。
2.2 筹备测试须要的镜像
2.2.1 筹备 MySQL 镜像
个别状况下，MySQL 应用官网 5.7 版本的镜像，MySQL 监控采集器应用的是 mysqld-exporter，也能够间接从 docker hub 下载：
docker pull mysql:5.7docker pull prom/mysqld-exporter2.2.2 筹备 ZooKeeper 镜像
ZooKeeper 应用的是官网 3.5.5 版本镜像，ZooKeeper 组件波及的监控有 jmx-prometheus-exporter 和 zookeeper-exporter，均从 docker hub 下载：
docker pull zookeeper:3.5.5docker pull sscaling/jmx-prometheus-exporterdocker pull josdotso/zookeeper-exporter2.2.3 筹备 GreatDB 镜像
抉择一个 GreatDB 的 tar 包，将其解压失去一个 ./greatdb 目录，再将 greatdb-service-docker.sh 文件拷贝到这个解压进去的./greatdb 目录里：
cp greatdb-service-docker.sh ./greatdb/将 greatdb Dockerfile 放到./greatdb 文件夹的同级目录下，而后执行以下命令构建 GreatDB 镜像：
docker build -t greatdb/greatdb:tag2021 .2.2.4 筹备 GreatDB 分布式集群部署/清理的镜像
下载集群部署脚本 cluster-setup，集群初始化脚本 init-zk 以及集群 helm charts 包（可征询 4.0 开发/测试组获取）
将上述资料放在同一目录下，编写如下 Dockerfile:
FROM debian:buster-slim as init-zkCOPY ./init-zk /root/init-zkRUN chmod +x /root/init-zkFROM debian:buster-slim as cluster-setup\*# Set aliyun repo for speed*RUN sed -i 's/deb.debian.org/mirrors.aliyun.com/g' /etc/apt/sources.list && \ sed -i 's/security.debian.org/mirrors.aliyun.com/g' /etc/apt/sources.listRUN apt-get -y update && \ apt-get -y install \ curl \ wgetRUN curl -L https://storage.googleapis.com/kubernetes-release/release/v1.20.1/bin/linux/amd64/kubectl -o /usr/local/bin/kubectl && \ chmod +x /usr/local/bin/kubectl && \ mkdir /root/.kube && \ wget https://get.helm.sh/helm-v3.5.3-linux-amd64.tar.gz && \ tar -zxvf helm-v3.5.3-linux-amd64.tar.gz && \ mv linux-amd64/helm /usr/local/bin/helmCOPY ./config /root/.kube/COPY ./helm /helmCOPY ./cluster-setup /执行以下命令构建所需镜像：
docker build --target init-zk -t greatdb/initzk:latest .docker build --target cluster-setup -t greatdb/cluster-setup:v1 .2.2.5 筹备测试用例的镜像
目前测试反对的用例有：bank、bank2、pbank、tpcc、flashback 等，每个用例都是一个可执行文件。
以 flashback 测例为例构建测试用例的镜像，先将用例下载到本地，在用例的同一目录下编写如下内容的 Dockerfile：
FROM debian:buster-slimCOPY ./flashback /RUN cd / && chmod +x ./flashback执行以下命令构建测试用例镜像：
docker build -t greatdb/testsuite-flashback:v1 .2.3 将筹备好的镜像上传到公有仓库中
创立公有仓库和上传镜像操作请参考：https://zhuanlan.zhihu.com/p/...
3. Chaos Mesh 的应用
3.1 搭建 GreatDB 分布式集群
在上一章 2.2.4 中 cluster-setup 目录下执行以下命令块去搭建测试集群：
./cluster-setup \-clustername=c0 \-namespace=test \-enable-monitor=true \-mysql-image=mysql:5.7 \-mysql-replica=3 \-mysql-auth=1 \-mysql-normal=1 \-mysql-global=1 \-mysql-partition=1 \-zookeeper-repository=zookeeper \-zookeeper-tag=3.5.5 \-zookeeper-replica=3 \-greatdb-repository=greatdb/greatdb \-greatdb-tag=tag202110 \-greatdb-replica=3 \-greatdb-serviceHost=172.16.70.249输入信息：
liuxinle@liuxinle-OptiPlex-5060:~/k8s/cluster-setup$ ./cluster-setup \\> -clustername=c0 \\> -namespace=test \\> -enable-monitor=true \\> -mysql-image=mysql:5.7 \\> -mysql-replica=3 \\> -mysql-auth=1 \\> -mysql-normal=1 \\> -mysql-global=1 \\> -mysql-partition=1 \\> -zookeeper-repository=zookeeper \\> -zookeeper-tag=3.5.5 \\> -zookeeper-replica=3 \\> -greatdb-repository=greatdb/greatdb \\> -greatdb-tag=tag202110 \\> -greatdb-replica=3 \\> -greatdb-serviceHost=172.16.70.249INFO[2021-10-14T10:41:52+08:00] SetUp the cluster ... NameSpace=testINFO[2021-10-14T10:41:52+08:00] create namespace ... INFO[2021-10-14T10:41:57+08:00] copy helm chart templates ... INFO[2021-10-14T10:41:57+08:00] setup ... Component=MySQLINFO[2021-10-14T10:41:57+08:00] exec helm install and update greatdb-cfg.yaml ... INFO[2021-10-14T10:42:00+08:00] waiting mysql pods running ... INFO[2021-10-14T10:44:27+08:00] setup ... Component=ZookeeperINFO[2021-10-14T10:44:28+08:00] waiting zookeeper pods running ... INFO[2021-10-14T10:46:59+08:00] update greatdb-cfg.yaml INFO[2021-10-14T10:46:59+08:00] setup ... Component=greatdbINFO[2021-10-14T10:47:00+08:00] waiting greatdb pods running ... INFO[2021-10-14T10:47:21+08:00] waiting cluster running ... INFO[2021-10-14T10:47:27+08:00] waiting prometheus server running... INFO[2021-10-14T10:47:27+08:00] Dump Cluster Info INFO[2021-10-14T10:47:27+08:00] SetUp success. ClusterName=c0 NameSpace=test执行如下命令，查看集群 pod 状态：
kubectl get pod -n test -o wide输入信息：
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESc0-auth0-mysql-0 2/2 Running 0 10m 10.244.87.18 liuxinle-optiplex-5060 <none> <none>c0-auth0-mysql-1 2/2 Running 0 9m23s 10.244.87.54 liuxinle-optiplex-5060 <none> <none>c0-auth0-mysql-2 2/2 Running 0 8m39s 10.244.87.57 liuxinle-optiplex-5060 <none> <none>c0-greatdb-0 2/2 Running 1 5m3s 10.244.87.58 liuxinle-optiplex-5060 <none> <none>c0-greatdb-1 2/2 Running 0 4m57s 10.244.87.20 liuxinle-optiplex-5060 <none> <none>c0-greatdb-2 2/2 Running 0 4m50s 10.244.87.47 liuxinle-optiplex-5060 <none> <none>c0-glob0-mysql-0 2/2 Running 0 10m 10.244.87.51 liuxinle-optiplex-5060 <none> <none>c0-glob0-mysql-1 2/2 Running 0 9m23s 10.244.87.41 liuxinle-optiplex-5060 <none> <none>c0-glob0-mysql-2 2/2 Running 0 8m38s 10.244.87.60 liuxinle-optiplex-5060 <none> <none>c0-nor0-mysql-0 2/2 Running 0 10m 10.244.87.29 liuxinle-optiplex-5060 <none> <none>c0-nor0-mysql-1 2/2 Running 0 9m29s 10.244.87.4 liuxinle-optiplex-5060 <none> <none>c0-nor0-mysql-2 2/2 Running 0 8m45s 10.244.87.25 liuxinle-optiplex-5060 <none> <none>c0-par0-mysql-0 2/2 Running 0 10m 10.244.87.55 liuxinle-optiplex-5060 <none> <none>c0-par0-mysql-1 2/2 Running 0 9m26s 10.244.87.13 liuxinle-optiplex-5060 <none> <none>c0-par0-mysql-2 2/2 Running 0 8m42s 10.244.87.21 liuxinle-optiplex-5060 <none> <none>c0-prometheus-server-6697649b76-fkvh9 2/2 Running 0 4m36s 10.244.87.37 liuxinle-optiplex-5060 <none> <none>c0-zookeeper-0 1/1 Running 1 7m35s 10.244.87.44 liuxinle-optiplex-5060 <none> <none>c0-zookeeper-1 1/1 Running 0 6m41s 10.244.87.30 liuxinle-optiplex-5060 <none> <none>c0-zookeeper-2 1/1 Running 0 6m10s 10.244.87.49 liuxinle-optiplex-5060 <none> <none>c0-zookeeper-initzk-7hbfs 0/1 Completed 0 7m35s 10.244.87.17 liuxinle-optiplex-5060 <none> <none>看到 c0-zookeeper-initzk-7hbfs 的状态是 Completed，其余 pod 的状态为 Running，示意集群搭建胜利。
3.2 在 GreatDB 分布式集群中应用 Chaos Mesh 做混沌测试
Chaos Mesh 在 kubernetes 环境反对注入的故障类型包含：模仿 Pod 故障、模仿网络故障、模仿压力场景等，这里咱们以模仿 Pod 故障中的 pod-kill 为例。
将试验配置写入到文件中 pod-kill.yaml，内容示例如下：
apiVersion: chaos-mesh.org/v1alpha1kind: PodChaos *# 要注入的故障类型*metadata: name: pod-failure-example namespace: test *# 测试集群pod所在的namespace*spec: action: pod-kill *# 要注入的具体故障类型* mode: all *# 指定试验的运行形式，all（示意选出所有符合条件的 Pod）* duration: '30s' *# 指定试验的持续时间* selector: labelSelectors: "app.kubernetes.io/component": "greatdb" *# 指定注入故障指标pod的标签，通过kubectl describe pod c0-greatdb-1 -n test 命令返回后果中Labels后的内容失去*创立故障试验，命令如下：
kubectl create -n test -f pod-kill.yaml创立完故障试验之后，执行命令 kubectl get pod -n test -o wide 后果如下：
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESc0-auth0-mysql-0 2/2 Running 0 14m 10.244.87.18 liuxinle-optiplex-5060 <none> <none>c0-auth0-mysql-1 2/2 Running 0 14m 10.244.87.54 liuxinle-optiplex-5060 <none> <none>c0-auth0-mysql-2 2/2 Running 0 13m 10.244.87.57 liuxinle-optiplex-5060 <none> <none>c0-greatdb-0 0/2 ContainerCreating 0 2s <none> liuxinle-optiplex-5060 <none> <none>c0-greatdb-1 0/2 ContainerCreating 0 2s <none> liuxinle-optiplex-5060 <none> <none>c0-glob0-mysql-0 2/2 Running 0 14m 10.244.87.51 liuxinle-optiplex-5060 <none> <none>c0-glob0-mysql-1 2/2 Running 0 14m 10.244.87.41 liuxinle-optiplex-5060 <none> <none>c0-glob0-mysql-2 2/2 Running 0 13m 10.244.87.60 liuxinle-optiplex-5060 <none> <none>c0-nor0-mysql-0 2/2 Running 0 14m 10.244.87.29 liuxinle-optiplex-5060 <none> <none>c0-nor0-mysql-1 2/2 Running 0 14m 10.244.87.4 liuxinle-optiplex-5060 <none> <none>c0-nor0-mysql-2 2/2 Running 0 13m 10.244.87.25 liuxinle-optiplex-5060 <none> <none>c0-par0-mysql-0 2/2 Running 0 14m 10.244.87.55 liuxinle-optiplex-5060 <none> <none>c0-par0-mysql-1 2/2 Running 0 14m 10.244.87.13 liuxinle-optiplex-5060 <none> <none>c0-par0-mysql-2 2/2 Running 0 13m 10.244.87.21 liuxinle-optiplex-5060 <none> <none>c0-prometheus-server-6697649b76-fkvh9 2/2 Running 0 9m24s 10.244.87.37 liuxinle-optiplex-5060 <none> <none>c0-zookeeper-0 1/1 Running 1 12m 10.244.87.44 liuxinle-optiplex-5060 <none> <none>c0-zookeeper-1 1/1 Running 0 11m 10.244.87.30 liuxinle-optiplex-5060 <none> <none>c0-zookeeper-2 1/1 Running 0 10m 10.244.87.49 liuxinle-optiplex-5060 <none> <none>c0-zookeeper-initzk-7hbfs 0/1 Completed 0 12m 10.244.87.17 liuxinle-optiplex-5060 <none> <none>能够看到有带 greatdb 名字的 pod 正在被重启，阐明注入故障胜利。
4. 在argo中编排测试流程
Argo 是一个开源的容器本地工作流引擎，用于在 Kubernetes 上实现工作，能够将多步骤工作流建模为一系列工作，实现测试流程编排。
咱们应用 argo 定义一个测试工作，根本的测试流程是固定的，如下所示：
测试流程的 step1 是部署测试集群，接着开启两个并行任务，step2 跑测试用例，模仿业务场景，step3 同时应用 Chaos Mesh 注入故障，step2 的测试用例执行完结之后，step4 终止故障注入，最初 step5 清理集群环境。
4.1 用 argo 编排一个混沌测试工作流（以 flashback 测试用例为例
1）批改 cluster-setup.yaml 中的 image 信息，改成步骤 2.2 筹备测试须要的镜像中本人传上去的集群部署/清理镜像名和 tag
2）批改 testsuite-flashback.yaml 中的 image 信息，改成步骤 2.2 筹备测试须要的镜像中本人传上去的测试用例镜像名和 tag
3）将集群部署、测试用例和工具模板的 yaml 文件全副应用 kubectl apply -n argo -f xxx.yaml 命令创立资源 （这些文件定义了一些 argo template，不便用户写 workflow 时候应用）
kubectl apply -n argo -f cluster-setup.yamlkubectl apply -n argo -f testsuite-flashback.yamlkubectl apply -n argo -f tools-template.yaml4）复制一份 workflow 模板文件 workflow-template.yaml，将模板文件中正文提醒的局部批改为本人的设置即可，而后执行以下命令创立混沌测试工作流：
kubectl apply -n argo -f workflow-template.yaml以下是一份 workflow 模板文件：
apiVersion: argoproj.io/v1alpha1kind: Workflowmetadata: generateName: chaostest-c0-0- name: chaostest-c0-0 namespace: argospec: entrypoint: test-entry #测试入口，在这里传入测试参数，填写clustername、namespace、host、greatdb镜像名和tag名等根本信息 serviceAccountName: argo arguments: parameters: - name: clustername value: c0 - name: namespace value: test - name: host value: 172.16.70.249 - name: port value: 30901 - name: password value: Bgview@2020 - name: user value: root - name: run-time value: 10m - name: greatdb-repository value: greatdb/greatdb - name: greatdb-tag value: tag202110 - name: nemesis value: kill_mysql_normal_master,kill_mysql_normal_slave,kill_mysql_partition_master,kill_mysql_partition_slave,kill_mysql_auth_master,kill_mysql_auth_slave,kill_mysql_global_master,kill_mysql_global_slave,kill_mysql_master,kill_mysql_slave,net_partition_mysql_normal,net_partition_mysql_partition,net_partition_mysql_auth,net_partition_mysql_global - name: mysql-partition value: 1 - name: mysql-global value: 1 - name: mysql-auth value: 1 - name: mysql-normal value: 2 templates: - name: test-entry steps: - - name: setup-greatdb-cluster # step.1 集群部署. 请指定正确的参数，次要是mysql和zookeeper的镜像名、tag名 templateRef: name: cluster-setup-template template: cluster-setup arguments: parameters: - name: namespace value: "{{workflow.parameters.namespace}}" - name: clustername value: "{{workflow.parameters.clustername}}" - name: mysql-image value: mysql:5.7.34 - name: mysql-replica value: 3 - name: mysql-auth value: "{{workflow.parameters.mysql-auth}}" - name: mysql-normal value: "{{workflow.parameters.mysql-normal}}" - name: mysql-partition value: "{{workflow.parameters.mysql-partition}}" - name: mysql-global value: "{{workflow.parameters.mysql-global}}" - name: enable-monitor value: false - name: zookeeper-repository value: zookeeper - name: zookeeper-tag value: 3.5.5 - name: zookeeper-replica value: 3 - name: greatdb-repository value: "{{workflow.parameters.greatdb-repository}}" - name: greatdb-tag value: "{{workflow.parameters.greatdb-tag}}" - name: greatdb-replica value: 3 - name: greatdb-serviceHost value: "{{workflow.parameters.host}}" - name: greatdb-servicePort value: "{{workflow.parameters.port}}" - - name: run-flashbacktest # step.2 运行测试用例,请替换为你要运行的测试用例template并指定正确的参数，次要是测试应用的表个数和大小 templateRef: name: flashback-test-template template: flashback arguments: parameters: - name: user value: "{{workflow.parameters.user}}" - name: password value: "{{workflow.parameters.password}}" - name: host value: "{{workflow.parameters.host}}" - name: port value: "{{workflow.parameters.port}}" - name: concurrency value: 16 - name: size value: 10000 - name: tables value: 10 - name: run-time value: "{{workflow.parameters.run-time}}" - name: single-statement value: true - name: manage-statement value: true - name: invoke-chaos-for-flashabck-test # step.3 注入故障，请指定正确的参数，这里run-time和interval别离定义了故障注入的工夫和频次，因而省略掉了终止故障注入步骤 templateRef: name: chaos-rto-template template: chaos-rto arguments: parameters: - name: user value: "{{workflow.parameters.user}}" - name: host value: "{{workflow.parameters.host}}" - name: password value: "{{workflow.parameters.password}}" - name: port value: "{{workflow.parameters.port}}" - name: k8s-config value: /root/.kube/config - name: namespace value: "{{workflow.parameters.namespace}}" - name: clustername value: "{{workflow.parameters.clustername}}" - name: prometheus value: '' - name: greatdb-job value: greatdb-monitor-greatdb - name: nemesis value: "{{workflow.parameters.nemesis}}" - name: nemesis-duration value: 1m - name: nemesis-mode value: default - name: wait-time value: 5m - name: check-time value: 5m - name: nemesis-scope value: 1 - name: nemesis-log value: true - name: enable-monitor value: false - name: run-time value: "{{workflow.parameters.run-time}}" - name: interval value: 1m - name: monitor-log value: false - name: enable-rto value: false - name: rto-qps value: 0.1 - name: rto-warm value: 5m - name: rto-time value: 1m - name: log-level value: debug - - name: flashbacktest-output # 输入测试用例是否通过的后果 templateRef: name: tools-template template: output-result arguments: parameters: - name: info value: "flashback test pass, with nemesis: {{workflow.parameters.nemesis}}" - - name: clean-greatdb-cluster # step.4 清理测试集群，这里的参数和step.1的参数统一 templateRef: name: cluster-setup-template template: cluster-setup arguments: parameters: - name: namespace value: "{{workflow.parameters.namespace}}" - name: clustername value: "{{workflow.parameters.clustername}}" - name: mysql-image value: mysql:5.7 - name: mysql-replica value: 3 - name: mysql-auth value: "{{workflow.parameters.mysql-auth}}" - name: mysql-normal value: "{{workflow.parameters.mysql-normal}}" - name: mysql-partition value: "{{workflow.parameters.mysql-partition}}" - name: mysql-global value: "{{workflow.parameters.mysql-global}}" - name: enable-monitor value: false - name: zookeeper-repository value: zookeeper - name: zookeeper-tag value: 3.5.5 - name: zookeeper-replica value: 3 - name: greatdb-repository value: "{{workflow.parameters.greatdb-repository}}" - name: greatdb-tag value: "{{workflow.parameters.greatdb-tag}}" - name: greatdb-replica value: 3 - name: greatdb-serviceHost value: "{{workflow.parameters.host}}" - name: greatdb-servicePort value: "{{workflow.parameters.port}}" - name: clean value: true - - name: echo-result templateRef: name: tools-template template: echo arguments: parameters: - name: info value: "{{item}}" withItems: - "{{steps.flashbacktest-output.outputs.parameters.result}}"至此，你曾经胜利应用 Chaos Mesh 进行了一次混沌测试，并胜利验证了分布式系统的稳定性。
Now enjoy GreatSQL, and enjoy Chaos Mesh :)