# Managing shard groups in a ClickHouse® cluster

You can arrange several [shards](../concepts/sharding.md) of a ClickHouse® cluster into a _shard group_ and then place tables in that group.

## Getting a list of shard groups in a cluster {#list-shard-groups}

{% list tabs group=instructions %}

- Management console {#console}

  1. In the [management console](https://console.yandex.cloud), select the folder containing the cluster.
  1. Navigate to **Managed Service for ClickHouse**.
  1. Click the name of your cluster and select the **Shard groups** tab.

- CLI {#cli}

  If you do not have the Yandex Cloud CLI yet, [install and initialize it](../../cli/quickstart.md#install).

  The folder used by default is the one specified when [creating](../../cli/operations/profile/profile-create.md) the CLI profile. To change the default folder, use the `yc config set folder-id <folder_ID>` command. You can also specify a different folder for any command using `--folder-name` or `--folder-id`. If you access a resource by its name, the search will be limited to the default folder. If you access a resource by its ID, the search will be global, i.e., through all folders based on access permissions.

  To get a list of shard groups in a cluster, run this command:

  ```bash
  yc managed-clickhouse shard-groups list \
     --cluster-name=<cluster_name>
  ```

  You can get the cluster name with the [list of clusters in the folder](cluster-list.md#list-clusters).

- REST API {#api}

  1. [Get an IAM token for API authentication](../api-ref/authentication.md) and put it into an environment variable:

     ```bash
     export IAM_TOKEN="<IAM_token>"
     ```

  1. Call the [Cluster.ListShardGroups](../api-ref/Cluster/listShardGroups.md) method, e.g., via the following [cURL](https://curl.se/) request:

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

     You can get the cluster ID with the [list of clusters in the folder](cluster-list.md#list-clusters).

  1. Check the [server response](../api-ref/Cluster/listShardGroups.md#yandex.cloud.mdb.clickhouse.v1.ListClusterShardGroupsResponse) to make sure your request was successful.

- gRPC API {#grpc-api}

  1. [Get an IAM token for API authentication](../api-ref/authentication.md) and put it into an environment variable:

     ```bash
     export IAM_TOKEN="<IAM_token>"
     ```

  1. Clone the [cloudapi](https://github.com/yandex-cloud/cloudapi) repository:
     
     ```bash
     cd ~/ && git clone --depth=1 https://github.com/yandex-cloud/cloudapi
     ```
     
     Below, we assume that the repository contents reside in the `~/cloudapi/` directory.
  1. Call the [ClusterService.ListShardGroups](../api-ref/grpc/Cluster/listShardGroups.md) method, e.g., via the following [gRPCurl](https://github.com/fullstorydev/grpcurl) request:

     ```bash
     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.ListShardGroups
     ```

     You can get the cluster ID with the [list of clusters in the folder](cluster-list.md#list-clusters).

  1. View the [server response](../api-ref/grpc/Cluster/listShardGroups.md#yandex.cloud.mdb.clickhouse.v1.ListClusterShardGroupsResponse) to make sure your request was successful.

{% endlist %}

## Getting detailed information about a shard group {#get-shard-group}

{% list tabs group=instructions %}

- Management console {#console}

  1. In the [management console](https://console.yandex.cloud), select the folder containing the cluster.
  1. Navigate to **Managed Service for&nbsp;ClickHouse**.
  1. Click the name of your cluster and select the **Shard groups** tab.
  1. Select the shard group to view detailed information.

- CLI {#cli}

  If you do not have the Yandex Cloud CLI yet, [install and initialize it](../../cli/quickstart.md#install).

  The folder used by default is the one specified when [creating](../../cli/operations/profile/profile-create.md) the CLI profile. To change the default folder, use the `yc config set folder-id <folder_ID>` command. You can also specify a different folder for any command using `--folder-name` or `--folder-id`. If you access a resource by its name, the search will be limited to the default folder. If you access a resource by its ID, the search will be global, i.e., through all folders based on access permissions.

  To view detailed information about a shard group in a cluster, run this command:

  ```bash
  yc managed-clickhouse shard-groups get \
    --cluster-name=<cluster_name> \
    --name=<shard_group_name>
  ```

  You can get the cluster name from the [list of clusters in your folder](cluster-list.md#list-clusters).

- REST API {#api}

  1. [Get an IAM token for API authentication](../api-ref/authentication.md) and put it into an environment variable:

     ```bash
     export IAM_TOKEN="<IAM_token>"
     ```

  1. Call the [Cluster.GetShardGroup](../api-ref/Cluster/getShardGroup.md) method, e.g., via the following [cURL](https://curl.se/) request:

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

     You can get the cluster ID with the [list of clusters in the folder](cluster-list.md#list-clusters), and the shard group name, with the [list of groups in the cluster](#list-shard-groups).

  1. View the [server response](../api-ref/Cluster/getShardGroup.md#yandex.cloud.mdb.clickhouse.v1.ShardGroup) to make sure your request was successful.

- gRPC API {#grpc-api}

  1. [Get an IAM token for API authentication](../api-ref/authentication.md) and put it into an environment variable:

     ```bash
     export IAM_TOKEN="<IAM_token>"
     ```

  1. Clone the [cloudapi](https://github.com/yandex-cloud/cloudapi) repository:
     
     ```bash
     cd ~/ && git clone --depth=1 https://github.com/yandex-cloud/cloudapi
     ```
     
     Below, we assume that the repository contents reside in the `~/cloudapi/` directory.
  1. Call the [ClusterService.GetShardGroup](../api-ref/grpc/Cluster/getShardGroup.md) method, e.g., via the following [gRPCurl](https://github.com/fullstorydev/grpcurl) request:

     ```bash
     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_group_name": "<shard_group_name>"
           }' \
       mdb.api.cloud.yandex.net:443 \
       yandex.cloud.mdb.clickhouse.v1.ClusterService.GetShardGroup
     ```

     You can get the cluster ID with the [list of clusters in the folder](cluster-list.md#list-clusters), and the shard group name, with the [list of groups in the cluster](#list-shard-groups).

  1. View the [server response](../api-ref/grpc/Cluster/getShardGroup.md#yandex.cloud.mdb.clickhouse.v1.ShardGroup) to make sure your request was successful.

{% endlist %}

## Creating a shard group {#create-shard-group}

{% list tabs group=instructions %}

- Management console {#console}

  1. In the [management console](https://console.yandex.cloud), select the folder containing the cluster.
  1. Navigate to **Managed Service for&nbsp;ClickHouse**.
  1. Click the name of your cluster and select the **Shard groups** tab.
  1. Click **Create shard group**.
  1. Fill in the form fields and click **Apply**.

- CLI {#cli}

  If you do not have the Yandex Cloud CLI yet, [install and initialize it](../../cli/quickstart.md#install).

  The folder used by default is the one specified when [creating](../../cli/operations/profile/profile-create.md) the CLI profile. To change the default folder, use the `yc config set folder-id <folder_ID>` command. You can also specify a different folder for any command using `--folder-name` or `--folder-id`. If you access a resource by its name, the search will be limited to the default folder. If you access a resource by its ID, the search will be global, i.e., through all folders based on access permissions.

  To create a shard group in a cluster, run this command:

  ```bash
  yc managed-clickhouse shard-groups create \
    --cluster-name=<cluster_name> \
    --name=<shard_group_name> \
    --description=<shard_group_description> \
    --shards=<list_of_shard_names>
  ```

  Where `--shards` is the list of shard names to include in the group.

  You can get the cluster name from the [list of clusters in your folder](cluster-list.md#list-clusters).

  You can get the shard names with the [list of shards in the cluster](shards.md#list-shards).


- Terraform {#tf}

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

     For more on how to create such a file, see the [Creating a cluster](cluster-create.md) section.
  1. Add the `shard_group` section to the Managed Service for ClickHouse® cluster description.

     ```hcl
     resource "yandex_mdb_clickhouse_cluster_v2" "<cluster_name>" {
       ...
       shard_group {
         name        = "<shard_group_name>"
         description = "<optional_description_for_shard_group>"
         shard_names = [
           # List of shards in the group
           "<shard_1_name>",
           ...
           "<shard_N_name>"
         ]
       }
     }
     ```

  1. 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.
     1. Run this command:
     
        ```bash
        terraform validate
        ```
     
        Terraform will show any errors found in your configuration files.

  1. Confirm resource changes.

     1. Run this command to view the planned changes:
     
        ```bash
        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.
     
     1. If everything looks correct, apply the changes:
        1. Run this command:
     
           ```bash
           terraform apply
           ```
     
        1. Confirm updating the resources.
        1. Wait for the operation to complete.

  For more information, see [this Terraform provider guide](../../terraform/resources/mdb_clickhouse_cluster.md).

  {% note warning "Timeouts" %}
  
  The Terraform provider sets the following timeouts for Managed Service for ClickHouse® cluster operations:
  
  * Creating a cluster, including by restoring from a backup: 60 minutes.
  * Updating a cluster: 90 minutes.
  * Deleting a cluster: 30 minutes.
  
  Operations exceeding the timeout are aborted.
  
  {% cut "How to change these limits" %}
  
  Add the `timeouts` section to your cluster description, such as the following:
  
  ```hcl
  resource "yandex_mdb_clickhouse_cluster_v2" "<cluster_name>" {
    ...
    timeouts = {
      create = "1h30m" # 1 hour 30 minutes
      update = "2h"    # 2 hours
      delete = "30m"   # 30 minutes
    }
  }
  ```
  
  {% endcut %}
  
  {% endnote %}


- REST API {#api}

  1. [Get an IAM token for API authentication](../api-ref/authentication.md) and put it into an environment variable:

     ```bash
     export IAM_TOKEN="<IAM_token>"
     ```

  1. Call the [Cluster.CreateShardGroup](../api-ref/Cluster/createShardGroup.md) method, e.g., via the following [cURL](https://curl.se/) request:

     ```bash
     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>/shardGroups' \
       --data '{
                 "shardGroupName": "<shard_group_name>",
                 "description": "<shard_group_description>",
                 "shardNames": [
                   "<shard_1>", "<shard_2>", ... "<shard_N>"
                 ]
               }'
     ```

     Where:

     * `shardGroupName`: Shard group name.
     * `description`: Shard group description.
     * `shardNames`: List of shards to include in the new group.

     You can get the cluster ID with the [list of clusters in the folder](cluster-list.md#list-clusters).

  1. Check the [server response](../api-ref/Cluster/createShardGroup.md#yandex.cloud.operation.Operation) to make sure your request was successful.

- gRPC API {#grpc-api}

  1. [Get an IAM token for API authentication](../api-ref/authentication.md) and put it into an environment variable:

     ```bash
     export IAM_TOKEN="<IAM_token>"
     ```

  1. Clone the [cloudapi](https://github.com/yandex-cloud/cloudapi) repository:
     
     ```bash
     cd ~/ && git clone --depth=1 https://github.com/yandex-cloud/cloudapi
     ```
     
     Below, we assume that the repository contents reside in the `~/cloudapi/` directory.
  1. Call the [ClusterService.CreateShardGroup](../api-ref/grpc/Cluster/createShardGroup.md) method, e.g., via the following [gRPCurl](https://github.com/fullstorydev/grpcurl) request:

     ```bash
     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_group_name": "<shard_group_name>",
               "description": "<shard_group_description>",
               "shard_names": [
                 "<shard_1>", "<shard_2>", ... "<shard_N>"
               ]
             }' \
         mdb.api.cloud.yandex.net:443 \
         yandex.cloud.mdb.clickhouse.v1.ClusterService.CreateShardGroup
     ```

     Where:

     * `shard_group_name`: Shard group name.
     * `description`: Shard group description.
     * `shard_names`: List of shards to include in the new group.

     You can get the cluster ID with the [list of clusters in the folder](cluster-list.md#list-clusters).

  1. View the [server response](../api-ref/grpc/Cluster/createShardGroup.md#yandex.cloud.operation.Operation) to make sure your request was successful.

{% endlist %}

## Updating a shard group {#update-shard-group}

{% list tabs group=instructions %}

- Management console {#console}

  1. In the [management console](https://console.yandex.cloud), select the folder containing the cluster.
  1. Navigate to **Managed Service for&nbsp;ClickHouse**.
  1. Click the name of your cluster and select the **Shard groups** tab.
  1. Click ![image](../../_assets/console-icons/ellipsis.svg) next to the shard group in question and select **Edit**.

- CLI {#cli}

  If you do not have the Yandex Cloud CLI yet, [install and initialize it](../../cli/quickstart.md#install).

  The folder used by default is the one specified when [creating](../../cli/operations/profile/profile-create.md) the CLI profile. To change the default folder, use the `yc config set folder-id <folder_ID>` command. You can also specify a different folder for any command using `--folder-name` or `--folder-id`. If you access a resource by its name, the search will be limited to the default folder. If you access a resource by its ID, the search will be global, i.e., through all folders based on access permissions.

  To update a shard group in a cluster, run this command:

  ```bash
  yc managed-clickhouse shard-groups update \
    --cluster-name=<cluster_name> \
    --name=<shard_group_name> \
    --description=<new_description_for_shard_group> \
    --shards=<new_list_of_shard_names>
  ```

  Where `--shards` is the new list of shard names to include in the group.

  This command replaces the existing list of shards in the group with the new one provided in the `--shards` parameter. Before running the command, make sure you have added all the required shards to the new list.

  You can get the cluster name from the [list of clusters in your folder](cluster-list.md#list-clusters).

  You can get the shard group name with the [list of shard groups in the cluster](#list-shard-groups).

  You can get the shard names with the [list of shards in the cluster](shards.md#list-shards).


- Terraform {#tf}

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

     For more on how to create such a file, see the [Creating a cluster](cluster-create.md) section.
  1. In the Managed Service for ClickHouse® cluster description, update the `shard_group` section for the shard group you need:

     ```hcl
     resource "yandex_mdb_clickhouse_cluster_v2" "<cluster_name>" {
       ...
       shard_group {
         name        = "<new_name_for_shard_group>"
         description = "<new_description_for_shard_group>"
         shard_names = [
           # New list of shards in the group
           "<shard_1_name>",
           ...
           "<shard_N_name>"
         ]
       }
     }
     ```

  1. 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.
     1. Run this command:
     
        ```bash
        terraform validate
        ```
     
        Terraform will show any errors found in your configuration files.

  1. Confirm resource changes.

     1. Run this command to view the planned changes:
     
        ```bash
        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.
     
     1. If everything looks correct, apply the changes:
        1. Run this command:
     
           ```bash
           terraform apply
           ```
     
        1. Confirm updating the resources.
        1. Wait for the operation to complete.

  For more information, see [this Terraform provider guide](../../terraform/resources/mdb_clickhouse_cluster.md).

  {% note warning "Timeouts" %}
  
  The Terraform provider sets the following timeouts for Managed Service for ClickHouse® cluster operations:
  
  * Creating a cluster, including by restoring from a backup: 60 minutes.
  * Updating a cluster: 90 minutes.
  * Deleting a cluster: 30 minutes.
  
  Operations exceeding the timeout are aborted.
  
  {% cut "How to change these limits" %}
  
  Add the `timeouts` section to your cluster description, such as the following:
  
  ```hcl
  resource "yandex_mdb_clickhouse_cluster_v2" "<cluster_name>" {
    ...
    timeouts = {
      create = "1h30m" # 1 hour 30 minutes
      update = "2h"    # 2 hours
      delete = "30m"   # 30 minutes
    }
  }
  ```
  
  {% endcut %}
  
  {% endnote %}


- REST API {#api}

  1. [Get an IAM token for API authentication](../api-ref/authentication.md) and put it into an environment variable:

     ```bash
     export IAM_TOKEN="<IAM_token>"
     ```

  1. Call the [Cluster.updateShardGroup](../api-ref/Cluster/updateShardGroup.md) method, e.g., via the following [cURL](https://curl.se/) request:

     {% note 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.
     
     {% endnote %}

     ```bash
     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>/shardGroups/<shard_group_name>' \
       --data '{
                 "updateMask": "description,shardNames",
                 "description": "<shard_group_description>",
                 "shardNames": [
                   "<shard_1>", "<shard_2>", ... "<shard_N>"
                 ]
               }'
     ```

     Where:

     * `updateMask`: Comma-separated string of settings to update.
     * `description`: New description for the shard group.
     * `shardNames`: New list of shards to include in the group. To learn shard names, get the [list of shards](shards.md#list-shards) in the cluster. This list will replace the current one, so make sure you have added all the required shards to the new list.

     You can get the cluster ID with the [list of clusters in the folder](cluster-list.md#list-clusters), and the shard group name, with the [list of groups in the cluster](#list-shard-groups).

  1. View the [server response](../api-ref/Cluster/updateShardGroup.md#yandex.cloud.operation.Operation) to make sure your request was successful.

- gRPC API {#grpc-api}

  1. [Get an IAM token for API authentication](../api-ref/authentication.md) and put it into an environment variable:

     ```bash
     export IAM_TOKEN="<IAM_token>"
     ```

  1. Clone the [cloudapi](https://github.com/yandex-cloud/cloudapi) repository:
     
     ```bash
     cd ~/ && git clone --depth=1 https://github.com/yandex-cloud/cloudapi
     ```
     
     Below, we assume that the repository contents reside in the `~/cloudapi/` directory.
  1. Call the [ClusterService.UpdateShardGroup](../api-ref/grpc/Cluster/updateShardGroup.md) method, e.g., via the following [gRPCurl](https://github.com/fullstorydev/grpcurl) request:

     {% note 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.
     
     {% cut "Format for listing settings" %}
     
     ```yaml
     "update_mask": {
         "paths": [
             "<setting_1>",
             "<setting_2>",
             ...
             "<setting_N>"
         ]
     }
     ```
     
     {% endcut %}
     
     {% endnote %}

     ```bash
     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_group_name": "<shard_group_name>",
             "update_mask": {
               "paths": [
                 "description", "shard_names"
               ]
             },
             "description": "<shard_group_description>",
             "shard_names": [
               "<shard_1>", "<shard_2>", ... "<shard_N>"
             ]
           }' \
       mdb.api.cloud.yandex.net:443 \
       yandex.cloud.mdb.clickhouse.v1.ClusterService.UpdateShardGroup
     ```

     Where:

     * `update_mask`: List of settings to update as an array of strings (`paths[]`).
     * `description`: New description for the shard group.
     * `shard_names`: New list of shards to include in the group. To learn shard names, get the [list of shards](shards.md#list-shards) in the cluster. This list will replace the current one, so make sure you have added all the required shards to the new list.

     You can get the cluster ID with the [list of clusters in the folder](cluster-list.md#list-clusters), and the shard group name, with the [list of groups in the cluster](#list-shard-groups).

  1. View the [server response](../api-ref/grpc/Cluster/updateShardGroup.md#yandex.cloud.operation.Operation) to make sure your request was successful.

{% endlist %}

## Deleting a shard group {#delete-shard-group}

Deleting a shard group does not affect the shards it contains, i.e., they remain in the cluster.

Tables created on the deleted group remain but become unusable: any attempts to query them will return errors. However, you can delete these tables before or after deleting the shard group.

{% list tabs group=instructions %}

- Management console {#console}

  1. In the [management console](https://console.yandex.cloud), select the folder containing the cluster.
  1. Navigate to **Managed Service for&nbsp;ClickHouse**.
  1. Click the name of your cluster and select the **Shard groups** tab.
  1. Click ![image](../../_assets/console-icons/ellipsis.svg) next to the shard group in question and select **Delete**.

- CLI {#cli}

  If you do not have the Yandex Cloud CLI yet, [install and initialize it](../../cli/quickstart.md#install).

  The folder used by default is the one specified when [creating](../../cli/operations/profile/profile-create.md) the CLI profile. To change the default folder, use the `yc config set folder-id <folder_ID>` command. You can also specify a different folder for any command using `--folder-name` or `--folder-id`. If you access a resource by its name, the search will be limited to the default folder. If you access a resource by its ID, the search will be global, i.e., through all folders based on access permissions.

  To delete a shard group in a cluster, run this command:

  ```bash
  yc managed-clickhouse shard-groups delete \
     --cluster-name=<cluster_name> \
     --name=<shard_group_name>
  ```

  You can get the cluster name from the [list of clusters in your folder](cluster-list.md#list-clusters).

  You can get the shard group name with the [list of shard groups in the cluster](#list-shard-groups).


- Terraform {#tf}

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

     For more on how to create such a file, see the [Creating a cluster](cluster-create.md) section.
  1. Delete the `shard_group` section for the group in question from the Managed Service for ClickHouse® cluster description.
  1. 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.
     1. Run this command:
     
        ```bash
        terraform validate
        ```
     
        Terraform will show any errors found in your configuration files.

  1. Type `yes` and press **Enter**.

     1. Run this command to view the planned changes:
     
        ```bash
        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.
     
     1. If everything looks correct, apply the changes:
        1. Run this command:
     
           ```bash
           terraform apply
           ```
     
        1. Confirm updating the resources.
        1. Wait for the operation to complete.

  For more information, see [this Terraform provider guide](../../terraform/resources/mdb_clickhouse_cluster.md).

  {% note warning "Timeouts" %}
  
  The Terraform provider sets the following timeouts for Managed Service for ClickHouse® cluster operations:
  
  * Creating a cluster, including by restoring from a backup: 60 minutes.
  * Updating a cluster: 90 minutes.
  * Deleting a cluster: 30 minutes.
  
  Operations exceeding the timeout are aborted.
  
  {% cut "How to change these limits" %}
  
  Add the `timeouts` section to your cluster description, such as the following:
  
  ```hcl
  resource "yandex_mdb_clickhouse_cluster_v2" "<cluster_name>" {
    ...
    timeouts = {
      create = "1h30m" # 1 hour 30 minutes
      update = "2h"    # 2 hours
      delete = "30m"   # 30 minutes
    }
  }
  ```
  
  {% endcut %}
  
  {% endnote %}


- REST API {#api}

  1. [Get an IAM token for API authentication](../api-ref/authentication.md) and put it into an environment variable:

     ```bash
     export IAM_TOKEN="<IAM_token>"
     ```

  1. Call the [Cluster.DeleteShardGroup](../api-ref/Cluster/deleteShardGroup.md) method, e.g., via the following [cURL](https://curl.se/) request:

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

     You can get the cluster ID with the [list of clusters in the folder](cluster-list.md#list-clusters), and the shard group name, with the [list of groups in the cluster](#list-shard-groups).

  1. View the [server response](../api-ref/Cluster/deleteShardGroup.md#yandex.cloud.operation.Operation) to make sure your request was successful.

- gRPC API {#grpc-api}

  1. [Get an IAM token for API authentication](../api-ref/authentication.md) and put it into an environment variable:

     ```bash
     export IAM_TOKEN="<IAM_token>"
     ```

  1. Clone the [cloudapi](https://github.com/yandex-cloud/cloudapi) repository:
     
     ```bash
     cd ~/ && git clone --depth=1 https://github.com/yandex-cloud/cloudapi
     ```
     
     Below, we assume that the repository contents reside in the `~/cloudapi/` directory.
  1. Call the [ClusterService.DeleteShardGroup](../api-ref/grpc/Cluster/deleteShardGroup.md) method, e.g., via the following [gRPCurl](https://github.com/fullstorydev/grpcurl) request:

     ```bash
     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_group_name": "<shard_group_name>"
           }' \
       mdb.api.cloud.yandex.net:443 \
       yandex.cloud.mdb.clickhouse.v1.ClusterService.DeleteShardGroup
     ```

     You can get the cluster ID with the [list of clusters in the folder](cluster-list.md#list-clusters), and the shard group name, with the [list of groups in the cluster](#list-shard-groups).

  1. View the [server response](../api-ref/grpc/Cluster/deleteShardGroup.md#yandex.cloud.operation.Operation) to make sure your request was successful.

{% endlist %}

_ClickHouse® is a registered trademark of [ClickHouse, Inc](https://clickhouse.com)._