Managing shards in a ClickHouse® cluster

If you do not have the Yandex Cloud (CLI) command line interface yet, install and initialize it.

The folder specified when creating the CLI profile is used by default. To change the default folder, use the yc config set folder-id <folder_ID> command. You can specify a different folder using the --folder-name or --folder-id parameter.

To create a shard, run the command below (not all the supported parameters are listed):

yc managed-clickhouse shards add <new_shard_name> \
  --cluster-name=<cluster_name> \
  --host zone-id=<availability_zone>,`
    `subnet-name=<subnet_name>

Where:

• <new_shard_name>: Must be unique within the cluster.

  It may contain Latin letters, numbers, hyphens, and underscores. The maximum length is 63 characters.

• --cluster-name: Cluster name.

  You can request the cluster name with a list of clusters in the folder.

• --host: Host parameters:

  • zone-id: Availability zone.
  • subnet-name: Subnet name.

1. Open the current Terraform configuration file with an infrastructure plan.

   For more information about creating this file, see Creating clusters.

2. Add the CLICKHOUSE-type host section with the shard_name field filled to the Managed Service for ClickHouse® cluster description or change existing hosts:

   resource "yandex_mdb_clickhouse_cluster" "<cluster_name>" {
     ...
     host {
       type       = "CLICKHOUSE"
       zone       = "<availability_zone>"
       subnet_id  = yandex_vpc_subnet.<subnet_in_availability_zone>.id
       shard_name = "<shard_name>"
     }
   }
   

3. Make sure the settings are correct.

   1. In the command line, navigate to the directory that contains the current Terraform configuration files defining the infrastructure.

   2. Run this command:

      terraform validate
      

      Terraform will show any errors found in your configuration files.

4. Confirm updating the resources.

   1. Run this command to view the planned changes:

      terraform plan
      

      If you described the configuration correctly, the terminal will display a list of the resources to update and their parameters. This is a verification step that does not apply changes to your resources.

   2. If everything looks correct, apply the changes:

      1. Run this command:

         terraform apply
         

      2. Confirm updating the resources.

      3. Wait for the operation to complete.

For more information, see the Terraform provider documentation.

resource "yandex_mdb_clickhouse_cluster" "<cluster_name>" {
  ...
  timeouts {
    create = "1h30m" # 1 hour 30 minutes
    update = "2h"    # 2 hours
    delete = "30m"   # 30 minutes
  }
}

1. Get an IAM token for API authentication and put it into the environment variable:

   export IAM_TOKEN="<IAM_token>"
   

2. Use the Cluster.AddShard method and send the following request, e.g., via cURL:

   1. Create a file named body.json and add the following contents to it:

      {
        "shardName": "<shard_name>",
        "configSpec": {
          "clickhouse": {
            "resources": {
              "resourcePresetId": "<host_class>",
              "diskSize": "<storage_size_in_bytes>",
              "diskTypeId": "<disk_type>"
            },
            "weight": "<shard_weight>"
          }
        },
        "hostSpecs": [
          {
            "zoneId": "<availability_zone>",
            "type": "CLICKHOUSE",
            "subnetId": "<subnet_ID>",
            "assignPublicIp": <public_access_to_host>,
            "shardName": "<shard_name>"
          }
        ],
        "copySchema": <data_schema_copying>
      }
      

      Where:

      • shardName: Shard name.

      • configSpec.clickhouse.resources: Host resources to add to the new shard:

        • resourcePresetId: Host class ID. You can request the list of available host classes with their IDs using the ResourcePreset.List method.
        • diskSize: Disk size in bytes.
        • diskTypeId: Disk type.

      • configSpec.clickhouse.weight: Shard weight.

        By default, each shard is assigned a weight of 1. If you assign a higher weight to a shard, the data will be distributed among the shards according to their weights.

        To calculate the shard priority during data distribution, all shard weights are added up, then the weight of each shard is divided by the total. For example, if one shard has a weight of 1 and another has a weight of 3, then the first shard’s priority is 1/4 and the second shard’s priority is 3/4. The higher the priority, the more data the shard will get.

        For more information, see the ClickHouse® documentation.

      • hostSpecs: Settings of hosts to add to the shard. The settings are represented as an array of elements, one for each host. Each element has the following structure:

        • zoneId: Availability zone.
        • type: Host type. You can only add CLICKHOUSE hosts to your shards.
        • subnetId: Subnet ID.
        • assignPublicIp: Internet access to the host via a public IP address, true or false.
        • shardName: Shard name.

      • copySchema: Copying the data schema from a random replica of one of the shards to the hosts of the new shard. The possible values are true or false.

   2. Run this request:

      curl \
        --request POST \
        --header "Authorization: Bearer $IAM_TOKEN" \
        --header "Content-Type: application/json" \
        --url 'https://mdb.api.cloud.yandex.net/managed-clickhouse/v1/clusters/<cluster_ID>/shards' \
        --data '@body.json'
      

      You can get the cluster ID with a list of clusters in the folder.

3. View the server response to make sure the request was successful.

1. Get an IAM token for API authentication and put it into the environment variable:

   export IAM_TOKEN="<IAM_token>"
   

2. Clone the cloudapi repository:

   cd ~/ && git clone --depth=1 https://github.com/yandex-cloud/cloudapi
   

   Below, we assume the repository contents are stored in the ~/cloudapi/ directory.

3. Use the ClusterService.AddShard call and send the following request, e.g., via gRPCurl:

   1. Create a file named body.json and add the following contents to it:

      {
        "cluster_id": "<cluster_ID>",
        "shard_name": "<shard_name>",
        "config_spec": {
          "clickhouse": {
            "resources": {
              "resource_preset_id": "<host_class>",
              "disk_size": "<storage_size_in_bytes>",
              "disk_type_id": "<disk_type>"
            },
            "weight": "<shard_weight>"
          }
        },
        "host_specs": [
          {
            "zone_id": "<availability_zone>",
            "type": "CLICKHOUSE",
            "subnet_id": "<subnet_ID>",
            "assign_public_ip": <public_access_to_host>,
            "shard_name": "<shard_name>"
          }
        ],
        "copy_schema": <data_schema_copying>
      }
      

      Where:

      • shard_name: Shard name.

      • config_spec.clickhouse.resources: Host resources to add to the new shard:

        • resource_preset_id: Host class ID. You can request the list of available host classes with their IDs using the ResourcePresetService.List method.
        • disk_size: Disk size in bytes.
        • disk_type_id: Disk type.

      • config_spec.clickhouse.weight: Shard weight.

        By default, each shard is assigned a weight of 1. If you assign a higher weight to a shard, the data will be distributed among the shards according to their weights.

        To calculate the shard priority during data distribution, all shard weights are added up, then the weight of each shard is divided by the total. For example, if one shard has a weight of 1 and another has a weight of 3, then the first shard’s priority is 1/4 and the second shard’s priority is 3/4. The higher the priority, the more data the shard will get.

        For more information, see the ClickHouse® documentation.

      • host_specs: Settings of hosts to add to the shard. The settings are represented as an array of elements, one for each host. Each element has the following structure:

        • zone_id: Availability zone.
        • type: Host type. You can only add CLICKHOUSE hosts to your shards.
        • subnet_id: Subnet ID.
        • assign_public_ip: Internet access to the host via a public IP address, true or false.
        • shard_name: Shard name.

      • copy_schema: Copying the data schema from a random replica of one of the shards to the hosts of the new shard. The possible values are true or false.

      You can get the cluster ID with a list of clusters in the folder.

   2. Run this request:

      grpcurl \
        -format json \
        -import-path ~/cloudapi/ \
        -import-path ~/cloudapi/third_party/googleapis/ \
        -proto ~/cloudapi/yandex/cloud/mdb/clickhouse/v1/cluster_service.proto \
        -rpc-header "Authorization: Bearer $IAM_TOKEN" \
        -d @ \
        mdb.api.cloud.yandex.net:443 \
        yandex.cloud.mdb.clickhouse.v1.ClusterService.AddShard \
        < body.json
      

4. View the server response to make sure the request was successful.

If you do not have the Yandex Cloud (CLI) command line interface yet, install and initialize it.

The folder specified when creating the CLI profile is used by default. To change the default folder, use the yc config set folder-id <folder_ID> command. You can specify a different folder using the --folder-name or --folder-id parameter.

To get a list of shards in a cluster, run the following command:

yc managed-clickhouse shards list --cluster-name=<cluster_name>

You can request the cluster name with a list of clusters in the folder.

1. Get an IAM token for API authentication and put it into the environment variable:

   export IAM_TOKEN="<IAM_token>"
   

2. Use the Cluster.ListShards method and send the following request, e.g., via cURL:

   curl \
     --request GET \
     --header "Authorization: Bearer $IAM_TOKEN" \
     --url 'https://mdb.api.cloud.yandex.net/managed-clickhouse/v1/clusters/<cluster_ID>/shards'
   

   You can get the cluster ID with a list of clusters in the folder.

3. View the server response to make sure the request was successful.

1. Get an IAM token for API authentication and put it into the environment variable:

   export IAM_TOKEN="<IAM_token>"
   

2. Clone the cloudapi repository:

   cd ~/ && git clone --depth=1 https://github.com/yandex-cloud/cloudapi
   

   Below, we assume the repository contents are stored in the ~/cloudapi/ directory.

3. Use the ClusterService.ListShards call and send the following request, e.g., via gRPCurl:

   grpcurl \
     -format json \
     -import-path ~/cloudapi/ \
     -import-path ~/cloudapi/third_party/googleapis/ \
     -proto ~/cloudapi/yandex/cloud/mdb/clickhouse/v1/cluster_service.proto \
     -rpc-header "Authorization: Bearer $IAM_TOKEN" \
     -d '{
             "cluster_id": "<cluster_ID>"
         }' \
     mdb.api.cloud.yandex.net:443 \
     yandex.cloud.mdb.clickhouse.v1.ClusterService.ListShards
   

   You can get the cluster ID with a list of clusters in the folder.

4. View the server response to make sure the request was successful.

If you do not have the Yandex Cloud (CLI) command line interface yet, install and initialize it.

The folder specified when creating the CLI profile is used by default. To change the default folder, use the yc config set folder-id <folder_ID> command. You can specify a different folder using the --folder-name or --folder-id parameter.

To change a shard in the cluster:

1. View a description of the CLI's shard change command:

   yc managed-clickhouse shards update --help
   

2. Start an operation, e.g., changing shard weight:

   yc managed-clickhouse shards update <shard_name> \
     --cluster-name=<cluster_name> \
     --weight=<shard_weight>
   

   Where:

   • <shard_name>: Can be requested with a list of shards in the cluster.

   • --cluster-name: Cluster name.

     You can request the cluster name with a list of clusters in the folder.

   • --weight: Shard weight. The minimum value is 0.

   When the operation is complete, the CLI displays information about the changed shard.

1. Get an IAM token for API authentication and put it into the environment variable:

   export IAM_TOKEN="<IAM_token>"
   

2. Use the Cluster.UpdateShard method and send the following request, e.g., via cURL:

   Warning

   The API method will assign default values to all the parameters of the object you are modifying unless you explicitly provide them in your request. To avoid this, list the settings you want to change in the updateMask parameter as a single comma-separated string.

   curl \
       --request PATCH \
       --header "Authorization: Bearer $IAM_TOKEN" \
       --header "Content-Type: application/json" \
       --url 'https://mdb.api.cloud.yandex.net/managed-clickhouse/v1/clusters/<cluster_ID>/shards/<shard_name>' \
       --data '{
                 "updateMask": "configSpec.clickhouse.config.<ClickHouse®_setup>,configSpec.clickhouse.resources,configSpec.clickhouse.weight",
                 "configSpec": {
                   "clickhouse": {
                     "config": {
                       <ClickHouse®_settings>
                     },
                     "resources": {
                       "resourcePresetId": "<host_class>",
                       "diskSize": "<storage_size_in_bytes>",
                       "diskTypeId": "<disk_type>"
                     },
                     "weight": "<shard_weight>"
                   }
                 }
               }'
   

   Where:

   • updateMask: List of parameters to update as a single string, separated by commas.

   • configSpec.clickhouse: Shard parameters to update:

     • config: ClickHouse® settings. For a list of available settings, see the method description.

     • resources: Host resources to add to the new shard:

       • resourcePresetId: Host class ID. You can request the list of available host classes with their IDs using the ResourcePreset.List method.
       • diskSize: Disk size in bytes.
       • diskTypeId: Disk type.

     • weight: Shard weight.

       By default, each shard is assigned a weight of 1. If you assign a higher weight to a shard, the data will be distributed among the shards according to their weights.

       To calculate the shard priority during data distribution, all shard weights are added up, then the weight of each shard is divided by the total. For example, if one shard has a weight of 1 and another has a weight of 3, then the first shard’s priority is 1/4 and the second shard’s priority is 3/4. The higher the priority, the more data the shard will get.

       For more information, see the ClickHouse® documentation.

   You can request the cluster ID with a list of clusters in the folder and the shard name with a list of shards in the cluster.

3. View the server response to make sure the request was successful.

1. Get an IAM token for API authentication and put it into the environment variable:

   export IAM_TOKEN="<IAM_token>"
   

2. Clone the cloudapi repository:

   cd ~/ && git clone --depth=1 https://github.com/yandex-cloud/cloudapi
   

   Below, we assume the repository contents are stored in the ~/cloudapi/ directory.

3. Use the ClusterService.UpdateShard call and send the following request, e.g., via gRPCurl:

   Warning

   The API method will assign default values to all the parameters of the object you are modifying unless you explicitly provide them in your request. To avoid this, list the settings you want to change in the update_mask parameter as an array of paths[] strings.

   Format for listing settings

   "update_mask": {
       "paths": [
           "<setting_1>",
           "<setting_2>",
           ...
           "<setting_N>"
       ]
   }
   

   grpcurl \
     -format json \
     -import-path ~/cloudapi/ \
     -import-path ~/cloudapi/third_party/googleapis/ \
     -proto ~/cloudapi/yandex/cloud/mdb/clickhouse/v1/cluster_service.proto \
     -rpc-header "Authorization: Bearer $IAM_TOKEN" \
     -d '{
           "cluster_id": "<cluster_ID>",
           "shard_name": "<shard_name>",
           "update_mask": {
             "paths": [
               "config_spec.clickhouse.config.<ClickHouse®_setup>",
               "config_spec.clickhouse.resources",
               "config_spec.clickhouse.weight"
             ]
           },
           "config_spec": {
             "clickhouse": {
               "config": {
                 <ClickHouse®_settings>
               },
               "resources": {
                 "resource_preset_id": "<host_class>",
                 "disk_size": "<storage_size_in_bytes>",
                 "disk_type_id": "<disk_type>"
               },
               "weight": "<shard_weight>"
             }
           }
         }' \
     mdb.api.cloud.yandex.net:443 \
     yandex.cloud.mdb.clickhouse.v1.ClusterService.UpdateShard
   

   Where:

   • update_mask: List of parameters to update as an array of paths[] strings.

   • config_spec.clickhouse: Shard parameters to update:

     • config: ClickHouse® settings. For a list of available settings, see the method description.

     • resources: Host resources to add to the new shard:

       • resource_preset_id: Host class ID. You can request the list of available host classes with their IDs using the ResourcePreset.List method.
       • disk_size: Disk size in bytes.
       • disk_type_id: Disk type.

     • weight: Shard weight.

       By default, each shard is assigned a weight of 1. If you assign a higher weight to a shard, the data will be distributed among the shards according to their weights.

       To calculate the shard priority during data distribution, all shard weights are added up, then the weight of each shard is divided by the total. For example, if one shard has a weight of 1 and another has a weight of 3, then the first shard’s priority is 1/4 and the second shard’s priority is 3/4. The higher the priority, the more data the shard will get.

       For more information, see the ClickHouse® documentation.

   You can request the cluster ID with a list of clusters in the folder and the shard name with a list of shards in the cluster.

4. View the server response to make sure the request was successful.

If you do not have the Yandex Cloud (CLI) command line interface yet, install and initialize it.

The folder specified when creating the CLI profile is used by default. To change the default folder, use the yc config set folder-id <folder_ID> command. You can specify a different folder using the --folder-name or --folder-id parameter.

To delete a shard from the cluster, run:

yc managed-clickhouse shards delete <shard_name> \
  --cluster-name=<cluster_name>

You can request the shard name with a list of shards in the cluster and the cluster name with a list of clusters in the folder.

1. Open the current Terraform configuration file with an infrastructure plan.

   For more information about creating this file, see Creating clusters.

2. Remove the host section with the shard description from the Managed Service for ClickHouse® cluster description.

3. Make sure the settings are correct.

   1. In the command line, navigate to the directory that contains the current Terraform configuration files defining the infrastructure.

   2. Run this command:

      terraform validate
      

      Terraform will show any errors found in your configuration files.

4. Type yes and press Enter.

   1. Run this command to view the planned changes:

      terraform plan
      

      If you described the configuration correctly, the terminal will display a list of the resources to update and their parameters. This is a verification step that does not apply changes to your resources.

   2. If everything looks correct, apply the changes:

      1. Run this command:

         terraform apply
         

      2. Confirm updating the resources.

      3. Wait for the operation to complete.

For more information, see the Terraform provider documentation.

resource "yandex_mdb_clickhouse_cluster" "<cluster_name>" {
  ...
  timeouts {
    create = "1h30m" # 1 hour 30 minutes
    update = "2h"    # 2 hours
    delete = "30m"   # 30 minutes
  }
}

1. Get an IAM token for API authentication and put it into the environment variable:

   export IAM_TOKEN="<IAM_token>"
   

2. Use the Cluster.DeleteShard method and send the following request, e.g., via cURL:

   curl \
     --request DELETE \
     --header "Authorization: Bearer $IAM_TOKEN" \
     --url 'https://mdb.api.cloud.yandex.net/managed-clickhouse/v1/clusters/<cluster_ID>/shards/<shard_name>'
   

   You can request the cluster ID with a list of clusters in the folder and the shard name with a list of shards in the cluster.

3. View the server response to make sure the request was successful.

1. Get an IAM token for API authentication and put it into the environment variable:

   export IAM_TOKEN="<IAM_token>"
   

2. Clone the cloudapi repository:

   cd ~/ && git clone --depth=1 https://github.com/yandex-cloud/cloudapi
   

   Below, we assume the repository contents are stored in the ~/cloudapi/ directory.

3. Use the ClusterService.DeleteShard call and send the following request, e.g., via gRPCurl:

   grpcurl \
     -format json \
     -import-path ~/cloudapi/ \
     -import-path ~/cloudapi/third_party/googleapis/ \
     -proto ~/cloudapi/yandex/cloud/mdb/clickhouse/v1/cluster_service.proto \
     -rpc-header "Authorization: Bearer $IAM_TOKEN" \
     -d '{
           "cluster_id": "<cluster_ID>",
           "shard_name": "<shard_name>"
         }' \
     mdb.api.cloud.yandex.net:443 \
     yandex.cloud.mdb.clickhouse.v1.ClusterService.DeleteShard
   

   You can request the cluster ID with a list of clusters in the folder and the shard name with a list of shards in the cluster.

4. View the server response to make sure the request was successful.