--- sidebar_label: Kubernetes title: 在 Kubernetes 上部署 TDengine 集群 --- 以下配置文件可以从 [GitHub 仓库](https://github.com/taosdata/TDengine-Operator/tree/3.0/src/tdengine) 下载。 ## 配置 Service 服务 创建一个 Service 配置文件：`taosd-service.yaml`，服务名称 `metadata.name` (此处为 "taosd") 将在下一步中使用到。添加 TDengine 所用到的所有端口： ```yaml --- apiVersion: v1 kind: Service metadata: name: "taosd" labels: app: "tdengine" spec: ports: - name: tcp6030 protocol: "TCP" port: 6030 - name: tcp6041 protocol: "TCP" port: 6041 selector: app: "tdengine" ``` ## 有状态服务 StatefulSet 根据 Kubernetes 对各类部署的说明，我们将使用 StatefulSet 作为 TDengine 的服务类型，创建文件 `tdengine.yaml`： ```yaml --- apiVersion: apps/v1 kind: StatefulSet metadata: name: "tdengine" labels: app: "tdengine" spec: serviceName: "taosd" replicas: 2 updateStrategy: type: RollingUpdate selector: matchLabels: app: "tdengine" template: metadata: name: "tdengine" labels: app: "tdengine" spec: containers: - name: "tdengine" image: "tdengine/tdengine:3.0.0.0" imagePullPolicy: "Always" envFrom: - configMapRef: name: taoscfg ports: - name: tcp6030 protocol: "TCP" containerPort: 6030 - name: tcp6041 protocol: "TCP" containerPort: 6041 env: # POD_NAME for FQDN config - name: POD_NAME valueFrom: fieldRef: fieldPath: metadata.name # SERVICE_NAME and NAMESPACE for fqdn resolve - name: SERVICE_NAME value: "taosd" - name: STS_NAME value: "tdengine" - name: STS_NAMESPACE valueFrom: fieldRef: fieldPath: metadata.namespace # TZ for timezone settings, we recommend to always set it. - name: TZ value: "Asia/Shanghai" # TAOS_ prefix will configured in taos.cfg, strip prefix and camelCase. - name: TAOS_SERVER_PORT value: "6030" # Must set if you want a cluster. - name: TAOS_FIRST_EP value: "$(STS_NAME)-0.$(SERVICE_NAME).$(STS_NAMESPACE).svc.cluster.local:$(TAOS_SERVER_PORT)" # TAOS_FQND should always be setted in k8s env. - name: TAOS_FQDN value: "$(POD_NAME).$(SERVICE_NAME).$(STS_NAMESPACE).svc.cluster.local" volumeMounts: - name: taosdata mountPath: /var/lib/taos readinessProbe: exec: command: - taos-check initialDelaySeconds: 5 timeoutSeconds: 5000 livenessProbe: exec: command: - taos-check initialDelaySeconds: 15 periodSeconds: 20 volumeClaimTemplates: - metadata: name: taosdata spec: accessModes: - "ReadWriteOnce" storageClassName: "standard" resources: requests: storage: "10Gi" ``` ## 使用 kubectl 命令部署 TDengine 集群 顺序执行以下命令。 ```bash kubectl apply -f taosd-service.yaml kubectl apply -f tdengine.yaml ``` 上面的配置将生成一个三节点的 TDengine 集群，dnode 是自动配置的，可以使用 show dnodes 命令查看当前集群的节点： ```bash kubectl exec -i -t tdengine-0 -- taos -s "show dnodes" kubectl exec -i -t tdengine-1 -- taos -s "show dnodes" kubectl exec -i -t tdengine-2 -- taos -s "show dnodes" ``` 输出如下： ``` Welcome to the TDengine shell from Linux, Client Version:3.0.0.0 Copyright (c) 2022 by TAOS Data, Inc. All rights reserved. taos> show dnodes id | endpoint | vnodes | support_vnodes | status | create_time | note | ============================================================================================================================================ 1 | tdengine-0.taosd.default.sv... | 0 | 256 | ready | 2022-08-10 13:14:57.285 | | 2 | tdengine-1.taosd.default.sv... | 0 | 256 | ready | 2022-08-10 13:15:11.302 | | 3 | tdengine-2.taosd.default.sv... | 0 | 256 | ready | 2022-08-10 13:15:23.290 | | Query OK, 3 rows in database (0.003655s) ``` ## 使能端口转发 利用 kubectl 端口转发功能可以使应用可以访问 Kubernetes 环境运行的 TDengine 集群。 ``` kubectl port-forward tdengine-0 6041:6041 & ``` 使用 curl 命令验证 TDengine REST API 使用的 6041 接口。 ``` $ curl -u root:taosdata -d "show databases" 127.0.0.1:6041/rest/sql Handling connection for 6041 {"code":0,"column_meta":[["name","VARCHAR",64],["create_time","TIMESTAMP",8],["vgroups","SMALLINT",2],["ntables","BIGINT",8],["replica","TINYINT",1],["strict","VARCHAR",4],["duration","VARCHAR",10],["keep","VARCHAR",32],["buffer","INT",4],["pagesize","INT",4],["pages","INT",4],["minrows","INT",4],["maxrows","INT",4],["comp","TINYINT",1],["precision","VARCHAR",2],["status","VARCHAR",10],["retention","VARCHAR",60],["single_stable","BOOL",1],["cachemodel","VARCHAR",11],["cachesize","INT",4],["wal_level","TINYINT",1],["wal_fsync_period","INT",4],["wal_retention_period","INT",4],["wal_retention_size","BIGINT",8],["wal_roll_period","INT",4],["wal_segment_size","BIGINT",8]],"data":[["information_schema",null,null,16,null,null,null,null,null,null,null,null,null,null,null,"ready",null,null,null,null,null,null,null,null,null,null],["performance_schema",null,null,10,null,null,null,null,null,null,null,null,null,null,null,"ready",null,null,null,null,null,null,null,null,null,null]],"rows":2} ``` ## 使用 dashboard 进行图形化管理 minikube 提供 dashboard 命令支持图形化管理界面。 ``` $ minikube dashboard * Verifying dashboard health ... * Launching proxy ... * Verifying proxy health ... * Opening http://127.0.0.1:46617/api/v1/namespaces/kubernetes-dashboard/services/http:kubernetes-dashboard:/proxy/ in your default browser... http://127.0.0.1:46617/api/v1/namespaces/kubernetes-dashboard/services/http:kubernetes-dashboard:/proxy/ ``` 对于某些公有云环境，minikube 绑定在 127.0.0.1 IP 地址上无法通过远程访问，需要使用 kubectl proxy 命令将端口映射到 0.0.0.0 IP 地址上，再通过浏览器访问虚拟机公网 IP 和端口以及相同的 dashboard URL 路径即可远程访问 dashboard。 ``` $ kubectl proxy --accept-hosts='^.*$' --address='0.0.0.0' ``` ## 集群扩容 TDengine 集群支持自动扩容： ```bash kubectl scale statefulsets tdengine --replicas=4 ``` 上面命令行中参数 `--replica=4` 表示要将 TDengine 集群扩容到 4 个节点，执行后首先检查 POD 的状态： ```bash kubectl get pods -l app=tdengine ``` 输出如下： ``` NAME READY STATUS RESTARTS AGE tdengine-0 1/1 Running 0 161m tdengine-1 1/1 Running 0 161m tdengine-2 1/1 Running 0 32m tdengine-3 1/1 Running 0 32m ``` 此时 POD 的状态仍然是 Running，TDengine 集群中的 dnode 状态要等 POD 状态为 `ready` 之后才能看到： ```bash kubectl exec -i -t tdengine-3 -- taos -s "show dnodes" ``` 扩容后的四节点 TDengine 集群的 dnode 列表: ``` Welcome to the TDengine shell from Linux, Client Version:3.0.0.0 Copyright (c) 2022 by TAOS Data, Inc. All rights reserved. taos> show dnodes id | endpoint | vnodes | support_vnodes | status | create_time | note | ============================================================================================================================================ 1 | tdengine-0.taosd.default.sv... | 0 | 256 | ready | 2022-08-10 13:14:57.285 | | 2 | tdengine-1.taosd.default.sv... | 0 | 256 | ready | 2022-08-10 13:15:11.302 | | 3 | tdengine-2.taosd.default.sv... | 0 | 256 | ready | 2022-08-10 13:15:23.290 | | 4 | tdengine-3.taosd.default.sv... | 0 | 256 | ready | 2022-08-10 13:33:16.039 | | Query OK, 4 rows in database (0.008377s) ``` ## 集群缩容 由于 TDengine 集群在扩缩容时会对数据进行节点间迁移，使用 kubectl 命令进行缩容需要首先使用 "drop dnodes" 命令，节点删除完成后再进行 Kubernetes 集群缩容。 注意：由于 Kubernetes Statefulset 中 Pod 的只能按创建顺序逆序移除，所以 TDengine drop dnode 也需要按照创建顺序逆序移除，否则会导致 Pod 处于错误状态。 ``` $ kubectl exec -i -t tdengine-0 -- taos -s "drop dnode 4" ``` ```bash $ kubectl exec -it tdengine-0 -- taos -s "show dnodes" Welcome to the TDengine shell from Linux, Client Version:3.0.0.0 Copyright (c) 2022 by TAOS Data, Inc. All rights reserved. taos> show dnodes id | endpoint | vnodes | support_vnodes | status | create_time | note | ============================================================================================================================================ 1 | tdengine-0.taosd.default.sv... | 0 | 256 | ready | 2022-08-10 13:14:57.285 | | 2 | tdengine-1.taosd.default.sv... | 0 | 256 | ready | 2022-08-10 13:15:11.302 | | 3 | tdengine-2.taosd.default.sv... | 0 | 256 | ready | 2022-08-10 13:15:23.290 | | Query OK, 3 rows in database (0.004861s) ``` 确认移除成功后（使用 kubectl exec -i -t tdengine-0 -- taos -s "show dnodes" 查看和确认 dnode 列表），使用 kubectl 命令移除 POD： ``` kubectl scale statefulsets tdengine --replicas=3 ``` 最后一个 POD 将会被删除。使用命令 kubectl get pods -l app=tdengine 查看POD状态： ``` $ kubectl get pods -l app=tdengine NAME READY STATUS RESTARTS AGE tdengine-0 1/1 Running 0 4m7s tdengine-1 1/1 Running 0 3m55s tdengine-2 1/1 Running 0 2m28s ``` POD删除后，需要手动删除PVC，否则下次扩容时会继续使用以前的数据导致无法正常加入集群。 ```bash $ kubectl delete pvc taosdata-tdengine-3 ``` 此时的集群状态是安全的，需要时还可以再次进行扩容： ```bash $ kubectl scale statefulsets tdengine --replicas=4 statefulset.apps/tdengine scaled it@k8s-2:~/TDengine-Operator/src/tdengine$ kubectl get pods -l app=tdengine NAME READY STATUS RESTARTS AGE tdengine-0 1/1 Running 0 35m tdengine-1 1/1 Running 0 34m tdengine-2 1/1 Running 0 12m tdengine-3 0/1 ContainerCreating 0 4s it@k8s-2:~/TDengine-Operator/src/tdengine$ kubectl get pods -l app=tdengine NAME READY STATUS RESTARTS AGE tdengine-0 1/1 Running 0 35m tdengine-1 1/1 Running 0 34m tdengine-2 1/1 Running 0 12m tdengine-3 0/1 Running 0 7s it@k8s-2:~/TDengine-Operator/src/tdengine$ kubectl exec -it tdengine-0 -- taos -s "show dnodes" Welcome to the TDengine shell from Linux, Client Version:3.0.0.0 Copyright (c) 2022 by TAOS Data, Inc. All rights reserved. Server is Community Edition. taos> show dnodes id | endpoint | vnodes | support_vnodes | status | create_time | offline reason | ====================================================================================================================================== 1 | tdengine-0.taosd.default.sv... | 0 | 4 | ready | 2022-07-25 17:38:49.012 | | 2 | tdengine-1.taosd.default.sv... | 1 | 4 | ready | 2022-07-25 17:39:01.517 | | 5 | tdengine-2.taosd.default.sv... | 0 | 4 | ready | 2022-07-25 18:01:36.479 | | 6 | tdengine-3.taosd.default.sv... | 0 | 4 | ready | 2022-07-25 18:13:54.411 | | Query OK, 4 row(s) in set (0.001348s) ``` ## 清理 TDengine 集群 完整移除 TDengine 集群，需要分别清理 statefulset、svc、configmap、pvc。 ```bash kubectl delete statefulset -l app=tdengine kubectl delete svc -l app=tdengine kubectl delete pvc -l app=tdengine kubectl delete configmap taoscfg ``` ## 常见错误 ### 错误一 未进行 "drop dnode" 直接进行缩容，由于 TDengine 尚未删除节点，缩容 pod 导致 TDengine 集群中部分节点处于 offline 状态。 ``` $ kubectl exec -it tdengine-0 -- taos -s "show dnodes" Welcome to the TDengine shell from Linux, Client Version:3.0.0.0 Copyright (c) 2022 by TAOS Data, Inc. All rights reserved. Server is Community Edition. taos> show dnodes id | endpoint | vnodes | support_vnodes | status | create_time | offline reason | ====================================================================================================================================== 1 | tdengine-0.taosd.default.sv... | 0 | 4 | ready | 2022-07-25 17:38:49.012 | | 2 | tdengine-1.taosd.default.sv... | 1 | 4 | ready | 2022-07-25 17:39:01.517 | | 5 | tdengine-2.taosd.default.sv... | 0 | 4 | offline | 2022-07-25 18:01:36.479 | status msg timeout | 6 | tdengine-3.taosd.default.sv... | 0 | 4 | offline | 2022-07-25 18:13:54.411 | status msg timeout | Query OK, 4 row(s) in set (0.001323s) ``` ### 错误二 TDengine 集群会持有 replica 参数，如果缩容后的节点数小于这个值，集群将无法使用： 创建一个库使用 replica 参数为 2，插入部分数据： ```bash kubectl exec -i -t tdengine-0 -- \ taos -s \ "create database if not exists test replica 2; use test; create table if not exists t1(ts timestamp, n int); insert into t1 values(now, 1)(now+1s, 2);" ``` 缩容到单节点： ```bash kubectl scale statefulsets tdengine --replicas=1 ``` 在 taos shell 中的所有数据库操作将无法成功。 ``` taos> show dnodes; id | end_point | vnodes | cores | status | role | create_time | offline reason | ====================================================================================================================================== 1 | tdengine-0.taosd.default.sv... | 2 | 40 | ready | any | 2021-06-01 15:55:52.562 | | 2 | tdengine-1.taosd.default.sv... | 1 | 40 | offline | any | 2021-06-01 15:56:07.212 | status msg timeout | Query OK, 2 row(s) in set (0.000845s) taos> show dnodes; id | end_point | vnodes | cores | status | role | create_time | offline reason | ====================================================================================================================================== 1 | tdengine-0.taosd.default.sv... | 2 | 40 | ready | any | 2021-06-01 15:55:52.562 | | 2 | tdengine-1.taosd.default.sv... | 1 | 40 | offline | any | 2021-06-01 15:56:07.212 | status msg timeout | Query OK, 2 row(s) in set (0.000837s) taos> use test; Database changed. taos> insert into t1 values(now, 3); DB error: Unable to resolve FQDN (0.013874s) ```