使用 Helm 部署 TDengine 集群

    Helm 会使用 kubectl 和 kubeconfig 的配置来操作 Kubernetes，可以参考 Rancher 安装 Kubernetes 的配置来进行设置。

    安装 TDengine Chart

    TDengine Chart 尚未发布到 Helm 仓库，当前可以从 GitHub 直接下载：

    获取当前 Kubernetes 的存储类：

    1. kubectl get storageclass

    在 minikube 默认为 standard.

    之后，使用 helm 命令安装：

    1. helm install tdengine tdengine-3.0.2.tgz \
    2.   --set storage.className=<your storage class name>

    在 minikube 环境下，可以设置一个较小的容量避免超出磁盘可用空间：

    1. export POD_NAME=$(kubectl get pods --namespace default \
    2.   -l "app.kubernetes.io/name=tdengine,app.kubernetes.io/instance=tdengine" \
    3.   -o jsonpath="{.items[0].metadata.name}")
    4. kubectl --namespace default exec $POD_NAME -- taos -s "show dnodes; show mnodes"
    5. kubectl --namespace default exec -it $POD_NAME -- taos

    可以创建一个表进行测试：

    1. kubectl --namespace default exec $POD_NAME -- \
    2.   taos -s "create database test;
    3.     use test;
    4.     create table t1 (ts timestamp, n int);
    5.     insert into t1 values(now, 1)(now + 1s, 2);
    6.     select * from t1;"

    TDengine 支持 values.yaml 自定义。

    通过 helm show values 可以获取 TDengine Chart 支持的全部 values 列表：

    1. helm show values tdengine-3.0.2.tgz

    你可以将结果保存为 values.yaml，之后可以修改其中的各项参数，如 replica 数量，存储类名称，容量大小，TDengine 配置等，然后使用如下命令安装 TDengine 集群：

    全部参数如下：

    1. # Default values for tdengine.
    2. # This is a YAML-formatted file.
    3. # Declare variables to be passed into helm templates.
    5. replicaCount: 1
    7. image:
    8.   prefix: tdengine/tdengine
    9.   #pullPolicy: Always
    10.   # Overrides the image tag whose default is the chart appVersion.
    11. #  tag: "3.0.2.0"
    13. service:
    14.   # ClusterIP is the default service type, use NodeIP only if you know what you are doing.
    15.   type: ClusterIP
    16.   ports:
    17.     # TCP range required
    18.     tcp: [6030, 6041, 6042, 6043, 6044, 6046, 6047, 6048, 6049, 6060]
    19.     # UDP range
    20.     udp: [6044, 6045]
    23. # Set timezone here, not in taoscfg
    24. timezone: "Asia/Shanghai"
    26. resources:
    27.   # We usually recommend not to specify default resources and to leave this as a conscious
    28.   # choice for the user. This also increases chances charts run on environments with little
    29.   # resources, such as Minikube. If you do want to specify resources, uncomment the following
    30.   # lines, adjust them as necessary, and remove the curly braces after 'resources:'.
    31.   # limits:
    32.   #   cpu: 100m
    33.   #   memory: 128Mi
    34.   # requests:
    35.   #   memory: 128Mi
    37. storage:
    38.   # Set storageClassName for pvc. K8s use default storage class if not set.
    40.   className: ""
    41.   dataSize: "100Gi"
    42.   logSize: "10Gi"
    44. nodeSelectors:
    45.   taosd:
    46.     # node selectors
    48. clusterDomainSuffix: ""
    49. # Config settings in taos.cfg file.
    50. #
    51. # The helm/k8s support will use environment variables for taos.cfg,
    52. # converting an upper-snake-cased variable like `TAOS_DEBUG_FLAG`,
    53. # to a camelCase taos config variable `debugFlag`.
    54. #
    55. # See the variable list at https://www.taosdata.com/cn/documentation/administrator .
    56. #
    57. # Note:
    58. # 1. firstEp/secondEp: should not be set here, it's auto generated at scale-up.
    59. # 2. serverPort: should not be set, we'll use the default 6030 in many places.
    60. # 3. fqdn: will be auto generated in kubernetes, user should not care about it.
    61. # 4. role: currently role is not supported - every node is able to be mnode and vnode.
    62. #
    63. # Btw, keep quotes "" around the value like below, even the value will be number or not.
    64. taoscfg:
    65.   # Starts as cluster or not, must be 0 or 1.
    66.   #   0: all pods will start as a separate TDengine server
    67.   #   1: pods will start as TDengine server cluster. [default]
    68.   CLUSTER: "1"
    70.   # number of replications, for cluster only
    71.   TAOS_REPLICA: "1"
    74.   # TAOS_NUM_OF_RPC_THREADS: number of threads for RPC
    75.   #TAOS_NUM_OF_RPC_THREADS: "2"
    77.   #
    78.   # TAOS_NUM_OF_COMMIT_THREADS: number of threads to commit cache data
    79.   #TAOS_NUM_OF_COMMIT_THREADS: "4"
    81.   # enable/disable installation / usage report
    82.   #TAOS_TELEMETRY_REPORTING: "1"
    84.   # time interval of system monitor, seconds
    85.   #TAOS_MONITOR_INTERVAL: "30"
    87.   # time interval of dnode status reporting to mnode, seconds, for cluster only
    88.   #TAOS_STATUS_INTERVAL: "1"
    90.   # time interval of heart beat from shell to dnode, seconds
    91.   #TAOS_SHELL_ACTIVITY_TIMER: "3"
    92.   # minimum sliding window time, milli-second
    93.   #TAOS_MIN_SLIDING_TIME: "10"
    95.   # minimum time window, milli-second
    96.   #TAOS_MIN_INTERVAL_TIME: "1"
    98.   # the compressed rpc message, option:
    99.   #  -1 (no compression)
    100.   #   0 (all message compressed),
    101.   # > 0 (rpc message body which larger than this value will be compressed)
    102.   #TAOS_COMPRESS_MSG_SIZE: "-1"
    104.   # max number of connections allowed in dnode
    105.   #TAOS_MAX_SHELL_CONNS: "50000"
    107.   # stop writing logs when the disk size of the log folder is less than this value
    108.   #TAOS_MINIMAL_LOG_DIR_G_B: "0.1"
    110.   # stop writing temporary files when the disk size of the tmp folder is less than this value
    111.   #TAOS_MINIMAL_TMP_DIR_G_B: "0.1"
    113.   # if disk free space is less than this value, taosd service exit directly within startup process
    114.   #TAOS_MINIMAL_DATA_DIR_G_B: "0.1"
    116.   # One mnode is equal to the number of vnode consumed
    117.   #TAOS_MNODE_EQUAL_VNODE_NUM: "4"
    119.   # enbale/disable http service
    120.   #TAOS_HTTP: "1"
    122.   # enable/disable system monitor
    123.   #TAOS_MONITOR: "1"
    125.   # enable/disable async log
    126.   #TAOS_ASYNC_LOG: "1"
    128.   #
    129.   # time of keeping log files, days
    130.   #TAOS_LOG_KEEP_DAYS: "0"
    132.   # The following parameters are used for debug purpose only.
    133.   # debugFlag 8 bits mask: FILE-SCREEN-UNUSED-HeartBeat-DUMP-TRACE_WARN-ERROR
    134.   # 131: output warning and error
    135.   # 135: output debug, warning and error
    136.   # 143: output trace, debug, warning and error to log
    137.   # 199: output debug, warning and error to both screen and file
    138.   # 207: output trace, debug, warning and error to both screen and file
    139.   #
    140.   # debug flag for all log type, take effect when non-zero value\
    141.   #TAOS_DEBUG_FLAG: "143"
    143.   # generate core file when service crash
    144.   #TAOS_ENABLE_CORE_FILE: "1"

    扩容

    关于扩容可参考上一节的说明，有一些额外的操作需要从 helm 的部署中获取。

    1. export STS_NAME=$(kubectl get statefulset \
    2.   -l "app.kubernetes.io/name=tdengine" \
    3.   -o jsonpath="{.items[0].metadata.name}")

    扩容操作极其简单，增加 replica 即可。以下命令将 TDengine 扩充到三节点：

    1. kubectl scale --replicas 3 statefulset/$STS_NAME

    使用命令 show dnodes 和 检查是否扩容成功。

    warning

    缩容操作并没有完整测试，可能造成数据风险，请谨慎使用。

    获取需要缩容的 dnode 列表，并手动 Drop。

    清理集群

    Helm 管理下，清理操作也变得简单：

      但 Helm 也不会自动移除 PVC，需要手动获取 PVC 然后删除掉。