容器开启数据服务之旅系列（一）：Kubernetes如何解自建PostgreSQL运维之痛

摘要： 通过阿里云Kubernetes容器服务,开启你的数据服务之旅 （一）云上运维自建数据库之痛，使用容器服务自动恢复数据库postgresql实例 概述 本文为大家介绍一种容器化的数据服务 posgresql db on ACK，通过使用云盘自动挂载实现的块存储PVC来做到数据库的免运维恢复。 **容器开启数据服务之旅系列（一）：Kubernetes如何解自建PostgreSQL运维之痛** **概述** 本文为大家介绍一种容器化的数据服务 posgresql db on ACK，通过使用云盘自动挂载实现的块存储PVC来做到数据库的免运维恢复。借助阿里云Kubernetes服务与阿里云存储资源的深度整合，打造数据库实例的免运维异地（ECS）恢复的不死神话。 **先决条件** 1\. 你已经通过阿里云容器服务创建了一个Kubernetes集群，详细步骤参见[创建Kubernetes集群](https://help.aliyun.com/document_detail/53752.html?spm=a2c4e.11153959.blogcont576061.13.6c9e3abdrxfvXF) 2\. 阿里云容器服务的存储插件（默认情况存储插件已经自动部署在阿里云Kubernetes容器服务） **从容器服务控制台创建一个posgresql实例** 使用三次点击来创建一个postgresql的不死实例 1\. 登录 https://cs.console.aliyun.com/ 2\. 点击 “应用目录” 3\. 选择 "postgresql"   4.（可选）选择你的Kubernetes集群. e.g. k8s-gpu 5.（可选）选择你的应用的命名空间。默认: default 6\. 给你的数据库应用取个容易记住的名字。 e.g. postgresql-online  7.(可选) 点击 “参数” 来定制你的数据库实例 1.修改 persistence.size: 20Gi 增加数据库云盘的容量 2.修改 persistence.storageClass: alicloud-disk-efficiency 调整数据卷所在云盘的性能。比如改为alicloud-disk-ssd 挂载ssd类型的   ``` ## Persist data to a persitent volume persistence: enabled: true ## A manually managed Persistent Volume and Claim ## Requires persistence.enabled: true ## If defined, PVC must be created manually before volume will be bound # existingClaim: ## database data Persistent Volume Storage Class ## if defined, user has to define storageClassName: alicloud-disk to support dynamic provision of alicloud-disk ## If defined, storageClassName: <storageclass> ## If set to "-", storageClassName: "", which disables dynamic provisioning ## If undefined (the default) or set to null, no storageClassName spec is ## set, choosing the default provisioner. (gp2 on AWS, standard on ## GKE, AWS & OpenStack) ## #storageClass: "alicloud-disk-ssd" storageClass: "alicloud-disk-efficiency" accessMode: ReadWriteOnce size: 20Gi subPath: "postgresql-db" ``` 8 点击 “部署”， 完成数据发布 9 点击 “Kubernetes 控制台”，查看部署实例   10 点击容器组，点击 postgresql-online-postgresql 查看数据库实例密码。容器实例启动在节点:cn-hangzhou.i-bp1fazljd8u2ylk2otdo   11 测试postgresql数据库的异地(ECS)恢复 1.添加测试数据 ``` ssh <public ip="" of="" kubernetes="" master="" node="">` # kubectl run my-pg-postgresql-client --rm --tty -i --image postgres \ --env "PGPASSWORD=$PGPASSWORD" \ --command -- psql -U postgres \ -h postgresql-online-postgresql postgres If you don't see a command prompt, try pressing enter. postgres=# create table t1 (id int); CREATE TABLE postgres=# insert into t1 values(10); INSERT 0 1 postgres=# select * from t1; id ---- 10 (1 row) ``` 驱逐数据库实例从ECS节点 i-bp1fazljd8u2ylk2otdo 到 i- ``` bp1fazljd8u2ylk2otdp #kubectl get pod -o wide | grep postgresql-online-postgresql postgresql-online-postgresql-78884fbcf6-6mfzz 1/1 Running 0 36m 172.30.4.4 cn-hangzhou.i-bp1fazljd8u2ylk2otdo #kubectl cordon cn-hangzhou.i-bp1fazljd8u2ylk2otdo #kubectl delete pod postgresql-online-postgresql-78884fbcf6-6mfzz pod "postgresql-online-postgresql-78884fbcf6-6mfzz" deleted # kubectl get pod -o wide|grep postgresql-online-postgresql #postgresql-online-postgresql-78884fbcf6-87ttg 0/1 Running 0 15s 172.30.3.5 cn-hangzhou.i-bp1fazljd8u2ylk2otdp ``` 检验数据，实例迁移， 数据库实例自动化恢复， 数据不丢失。 ``` # kubectl get pod -o wide|grep postgresql-online-postgresql #postgresql-online-postgresql-78884fbcf6-87ttg 0/1 Running 0 15s 172.30.3.5 cn-hangzhou.i-bp1fazljd8u2ylk2otdp kubectl run my-pg-postgresql-client --rm --tty -i --image postgres \ > --env "PGPASSWORD=$PGPASSWORD" \ > --command -- psql -U postgres \ > -h postgresql-online-postgresql postgres If you don't see a command prompt, try pressing enter. postgres=# select * from t1; id ---- 10 (1 row) ``` **CLI控: 使用命令行完成postgresql实例的创建，迁移验证** **login k8s master and deploy an postgresql db in seconds.** ``` ssh <public ip="" of="" kubernetes="" master="" node=""> helm install -n postgresql-online --set 'persistence.size=30Gi,persistence.storageClass=alicloud-disk-ssd' stable/postgresql ``` To get your user password run: ``` PGPASSWORD=$(kubectl get secret --namespace default my-pg-postgresql -o jsonpath="{.data.postgres-password}" | base64 --decode; echo) ``` To connect to your database run the following command (using the env variable from above): ``` kubectl run my-pg-postgresql-client --rm --tty -i --image postgres \ --env "PGPASSWORD=$PGPASSWORD" \ --command -- psql -U postgres \ -h postgresql-online-postgresql postgres ``` To connect to your database directly from outside the K8s cluster: ``` PGHOST=127.0.0.1 PGPORT=5432 # Execute the following commands to route the connection: export POD_NAME=$(kubectl get pods --namespace default -l "app=my-pg-postgresql" -o jsonpath="{.items[0].metadata.name}") kubectl port-forward $POD_NAME 5432:5432 #kubectl get pod -o wide | grep postgresql-online-postgresql postgresql-online-postgresql-78884fbcf6-6mfzz 1/1 Running 0 36m 172.30.4.4 cn-hangzhou.i-bp1fazljd8u2ylk2otdo #kubectl cordon cn-hangzhou.i-bp1fazljd8u2ylk2otdo #kubectl delete pod postgresql-online-postgresql-78884fbcf6-6mfzz pod "postgresql-online-postgresql-78884fbcf6-6mfzz" deleted # kubectl get pod -o wide|grep postgresql-online-postgresql #postgresql-online-postgresql-78884fbcf6-87ttg 0/1 Running 0 15s 172.30.3.5 cn-hangzhou.i-bp1fazljd8u2ylk2otdp ``` Test original postgresql db could be recovered on different node. ``` #kubectl get pod -o wide|grep postgresql-online-postgresql #postgresql-online-postgresql-78884fbcf6-87ttg 0/1 Running 0 15s 172.30.3.5 cn-hangzhou.i-bp1fazljd8u2ylk2otdp kubectl run my-pg-postgresql-client --rm --tty -i --image postgres \ > --env "PGPASSWORD=$PGPASSWORD" \ > --command -- psql -U postgres \ > -h postgresql-online-postgresql postgres If you don't see a command prompt, try pressing enter. postgres=# select * from t1; id ---- 10 (1 row) ``` [**原文链接**](http://click.aliyun.com/m/46373/) **阅读更多干货好文，请关注扫描以下二维码：** </public></public></storageclass>