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| title | titleSuffix | description | author | ms.subservice | ms.topic | ms.date | ms.author | ms.custom |
|---|---|---|---|---|---|---|---|---|
| Copy data from HDFS | Azure Data Factory & Azure Synapse | Learn how to copy data from a cloud or on-premises HDFS source to supported sink data stores by using Copy activity in an Azure Data Factory or Synapse Analytics pipeline. | jianleishen | data-movement | conceptual | 10/20/2023 | jianleishen | ['synapse', 'sfi-image-nochange'] |
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---
title: Copy data from HDFS
titleSuffix: Azure Data Factory & Azure Synapse
description: Learn how to copy data from a cloud or on-premises HDFS source to supported sink data stores by using Copy activity in an Azure Data Factory or Synapse Analytics pipeline.
author: jianleishen
ms.subservice: data-movement
ms.topic: conceptual
ms.date: 10/20/2023
ms.author: jianleishen
ms.custom:
- synapse
- sfi-image-nochange
---
# Copy data from the HDFS server using Azure Data Factory or Synapse Analytics
[!INCLUDE[appliesto-adf-asa-md](includes/appliesto-adf-asa-md.md)]
This article outlines how to copy data from the Hadoop Distributed File System (HDFS) server. To learn more, read the introductory articles for [Azure Data Factory](introduction.md) and [Synapse Analytics](../synapse-analytics/overview-what-is.md).
## Supported capabilities
This HDFS connector is supported for the following capabilities:
| Supported capabilities|IR |
|---------| --------|
|[Copy activity](copy-activity-overview.md) (source/-)|① ②|
|[Lookup activity](control-flow-lookup-activity.md)|① ②|
|[Delete activity](delete-activity.md)|① ②|
*① Azure integration runtime ② Self-hosted integration runtime*
Specifically, the HDFS connector supports:
- Copying files by using *Windows* (Kerberos) or *Anonymous* authentication.
- Copying files by using the *webhdfs* protocol or *built-in DistCp* support.
- Copying files as is or by parsing or generating files with the [supported file formats and compression codecs](supported-file-formats-and-compression-codecs.md).
## Prerequisites
[!INCLUDE [data-factory-v2-integration-runtime-requirements](includes/data-factory-v2-integration-runtime-requirements.md)]
> [!NOTE]
> Make sure that the integration runtime can access *all* the [name node server]:[name node port] and [data node servers]:[data node port] of the Hadoop cluster. The default [name node port] is 50070, and the default [data node port] is 50075.
## Get started
[!INCLUDE [data-factory-v2-connector-get-started](includes/data-factory-v2-connector-get-started.md)]
## Create a linked service to HDFS using UI
Use the following steps to create a linked service to HDFS in the Azure portal UI.
1. Browse to the Manage tab in your Azure Data Factory or Synapse workspace and select Linked Services, then click New:
# [Azure Data Factory](#tab/data-factory)
:::image type="content" source="media/doc-common-process/new-linked-service.png" alt-text="Create a new linked service with Azure Data Factory UI.":::
# [Azure Synapse](#tab/synapse-analytics)
:::image type="content" source="media/doc-common-process/new-linked-service-synapse.png" alt-text="Create a new linked service with Azure Synapse UI.":::
2. Search for HDFS and select the HDFS connector.
:::image type="content" source="media/connector-hdfs/hdfs-connector.png" alt-text="Select the HDFS connector.":::
1. Configure the service details, test the connection, and create the new linked service.
:::image type="content" source="media/connector-hdfs/configure-hdfs-linked-service.png" alt-text="Configure a linked service to HDFS.":::
## Connector configuration details
The following sections provide details about properties that are used to define Data Factory entities specific to HDFS.
## Linked service properties
The following properties are supported for the HDFS linked service:
| Property | Description | Required |
|:--- |:--- |:--- |
| type | The *type* property must be set to *Hdfs*. | Yes |
| url |The URL to the HDFS |Yes |
| authenticationType | The allowed values are *Anonymous* or *Windows*. <br><br> To set up your on-premises environment, see the [Use Kerberos authentication for the HDFS connector](#use-kerberos-authentication-for-the-hdfs-connector) section. |Yes |
| userName |The username for Windows authentication. For Kerberos authentication, specify **\<username>@\<domain>.com**. |Yes (for Windows authentication) |
| password |The password for Windows authentication. Mark this field as a SecureString to store it securely, or [reference a secret stored in an Azure key vault](store-credentials-in-key-vault.md). |Yes (for Windows Authentication) |
| connectVia | The [integration runtime](concepts-integration-runtime.md) to be used to connect to the data store. To learn more, see the [Prerequisites](#prerequisites) section. If the integration runtime isn't specified, the service uses the default Azure Integration Runtime. |No |
**Example: using Anonymous authentication**
```json
{
"name": "HDFSLinkedService",
"properties": {
"type": "Hdfs",
"typeProperties": {
"url" : "http://<machine>:50070/webhdfs/v1/",
"authenticationType": "Anonymous",
"userName": "hadoop"
},
"connectVia": {
"referenceName": "<name of Integration Runtime>",
"type": "IntegrationRuntimeReference"
}
}
}
```
**Example: using Windows authentication**
```json
{
"name": "HDFSLinkedService",
"properties": {
"type": "Hdfs",
"typeProperties": {
"url" : "http://<machine>:50070/webhdfs/v1/",
"authenticationType": "Windows",
"userName": "<username>@<domain>.com (for Kerberos auth)",
"password": {
"type": "SecureString",
"value": "<password>"
}
},
"connectVia": {
"referenceName": "<name of Integration Runtime>",
"type": "IntegrationRuntimeReference"
}
}
}
```
## Dataset properties
For a full list of sections and properties that are available for defining datasets, see [Datasets](concepts-datasets-linked-services.md).
[!INCLUDE [data-factory-v2-file-formats](includes/data-factory-v2-file-formats.md)]
The following properties are supported for HDFS under `location` settings in the format-based dataset:
| Property | Description | Required |
| ---------- | ------------------------------------------------------------ | -------- |
| type | The *type* property under `location` in the dataset must be set to *HdfsLocation*. | Yes |
| folderPath | The path to the folder. If you want to use a wildcard to filter the folder, skip this setting and specify the path in activity source settings. | No |
| fileName | The file name under the specified folderPath. If you want to use a wildcard to filter files, skip this setting and specify the file name in activity source settings. | No |
**Example:**
```json
{
"name": "DelimitedTextDataset",
"properties": {
"type": "DelimitedText",
"linkedServiceName": {
"referenceName": "<HDFS linked service name>",
"type": "LinkedServiceReference"
},
"schema": [ < physical schema, optional, auto retrieved during authoring > ],
"typeProperties": {
"location": {
"type": "HdfsLocation",
"folderPath": "root/folder/subfolder"
},
"columnDelimiter": ",",
"quoteChar": "\"",
"firstRowAsHeader": true,
"compressionCodec": "gzip"
}
}
}
```
## Copy activity properties
For a full list of sections and properties that are available for defining activities, see [Pipelines and activities](concepts-pipelines-activities.md). This section provides a list of properties that are supported by the HDFS source.
### HDFS as source
[!INCLUDE [data-factory-v2-file-formats](includes/data-factory-v2-file-formats.md)]
The following properties are supported for HDFS under `storeSettings` settings in the format-based Copy source:
| Property | Description | Required |
| ------------------------ | ------------------------------------------------------------ | --------------------------------------------- |
| type | The *type* property under `storeSettings` must be set to **HdfsReadSettings**. | Yes |
| ***Locate the files to copy*** | | |
| OPTION 1: static path<br> | Copy from the folder or file path that's specified in the dataset. If you want to copy all files from a folder, additionally specify `wildcardFileName` as `*`. | |
| OPTION 2: wildcard<br>- wildcardFolderPath | The folder path with wildcard characters to filter source folders. <br>Allowed wildcards are: `*` (matches zero or more characters) and `?` (matches zero or single character). Use `^` to escape if your actual folder name has a wildcard or this escape character inside. <br>For more examples, see [Folder and file filter examples](#folder-and-file-filter-examples). | No |
| OPTION 2: wildcard<br>- wildcardFileName | The file name with wildcard characters under the specified folderPath/wildcardFolderPath to filter source files. <br>Allowed wildcards are: `*` (matches zero or more characters) and `?` (matches zero or single character); use `^` to escape if your actual file name has a wildcard or this escape character inside. For more examples, see [Folder and file filter examples](#folder-and-file-filter-examples). | Yes |
| OPTION 3: a list of files<br>- fileListPath | Indicates to copy a specified file set. Point to a text file that includes a list of files you want to copy (one file per line, with the relative path to the path configured in the dataset).<br/>When you use this option, do not specify file name in the dataset. For more examples, see [File list examples](#file-list-examples). |No |
| ***Additional settings*** | | |
| recursive | Indicates whether the data is read recursively from the subfolders or only from the specified folder. When `recursive` is set to *true* and the sink is a file-based store, an empty folder or subfolder isn't copied or created at the sink. <br>Allowed values are *true* (default) and *false*.<br>This property doesn't apply when you configure `fileListPath`. |No |
| deleteFilesAfterCompletion | Indicates whether the binary files will be deleted from source store after successfully moving to the destination store. The file deletion is per file, so when copy activity fails, you will see some files have already been copied to the destination and deleted from source, while others are still remaining on source store. <br/>This property is only valid in binary files copy scenario. The default value: false. |No |
| modifiedDatetimeStart | Files are filtered based on the attribute *Last Modified*. <br>The files are selected if their last modified time is greater than or equal to `modifiedDatetimeStart` and less than `modifiedDatetimeEnd`. The time is applied to the UTC time zone in the format of *2018-12-01T05:00:00Z*. <br> The properties can be NULL, which means that no file attribute filter is applied to the dataset. When `modifiedDatetimeStart` has a datetime value but `modifiedDatetimeEnd` is NULL, it means that the files whose last modified attribute is greater than or equal to the datetime value are selected. When `modifiedDatetimeEnd` has a datetime value but `modifiedDatetimeStart` is NULL, it means that the files whose last modified attribute is less than the datetime value are selected.<br/>This property doesn't apply when you configure `fileListPath`. | No |
| modifiedDatetimeEnd | Same as above.
| enablePartitionDiscovery | For files that are partitioned, specify whether to parse the partitions from the file path and add them as additional source columns.<br/>Allowed values are **false** (default) and **true**. | No |
| partitionRootPath | When partition discovery is enabled, specify the absolute root path in order to read partitioned folders as data columns.<br/><br/>If it is not specified, by default,<br/>- When you use file path in dataset or list of files on source, partition root path is the path configured in dataset.<br/>- When you use wildcard folder filter, partition root path is the sub-path before the first wildcard.<br/><br/>For example, assuming you configure the path in dataset as "root/folder/year=2020/month=08/day=27":<br/>- If you specify partition root path as "root/folder/year=2020", copy activity will generate two more columns `month` and `day` with value "08" and "27" respectively, in addition to the columns inside the files.<br/>- If partition root path is not specified, no extra column will be generated. | No |
| maxConcurrentConnections | The upper limit of concurrent connections established to the data store during the activity run. Specify a value only when you want to limit concurrent connections.| No |
| ***DistCp settings*** | | |
| distcpSettings | The property group to use when you use HDFS DistCp. | No |
| resourceManagerEndpoint | The YARN (Yet Another Resource Negotiator) endpoint | Yes, if using DistCp |
| tempScriptPath | A folder path that's used to store the temp DistCp command script. The script file is generated and will be removed after the Copy job is finished. | Yes, if using DistCp |
| distcpOptions | Additional options provided to DistCp command. | No |
**Example:**
```json
"activities":[
{
"name": "CopyFromHDFS",
"type": "Copy",
"inputs": [
{
"referenceName": "<Delimited text input dataset name>",
"type": "DatasetReference"
}
],
"outputs": [
{
"referenceName": "<output dataset name>",
"type": "DatasetReference"
}
],
"typeProperties": {
"source": {
"type": "DelimitedTextSource",
"formatSettings":{
"type": "DelimitedTextReadSettings",
"skipLineCount": 10
},
"storeSettings":{
"type": "HdfsReadSettings",
"recursive": true,
"distcpSettings": {
"resourceManagerEndpoint": "resourcemanagerendpoint:8088",
"tempScriptPath": "/usr/hadoop/tempscript",
"distcpOptions": "-m 100"
}
}
},
"sink": {
"type": "<sink type>"
}
}
}
]
```
### Folder and file filter examples
This section describes the resulting behavior if you use a wildcard filter with the folder path and file name.
| folderPath | fileName | recursive | Source folder structure and filter result (files in **bold** are retrieved) |
| :--------- | :------------------- | :-------- | :----------------------------------------------------------- |
| `Folder*` | (empty, use default) | false | FolderA<br/> **File1.csv**<br/> **File2.json**<br/> Subfolder1<br/> File3.csv<br/> File4.json<br/> File5.csv<br/>AnotherFolderB<br/> File6.csv |
| `Folder*` | (empty, use default) | true | FolderA<br/> **File1.csv**<br/> **File2.json**<br/> Subfolder1<br/> **File3.csv**<br/> **File4.json**<br/> **File5.csv**<br/>AnotherFolderB<br/> File6.csv |
| `Folder*` | `*.csv` | false | FolderA<br/> **File1.csv**<br/> File2.json<br/> Subfolder1<br/> File3.csv<br/> File4.json<br/> File5.csv<br/>AnotherFolderB<br/> File6.csv |
| `Folder*` | `*.csv` | true | FolderA<br/> **File1.csv**<br/> File2.json<br/> Subfolder1<br/> **File3.csv**<br/> File4.json<br/> **File5.csv**<br/>AnotherFolderB<br/> File6.csv |
### File list examples
This section describes the behavior that results from using a file list path in the Copy activity source. It assumes that you have the following source folder structure and want to copy the files that are in bold type:
| Sample source structure | Content in FileListToCopy.txt | Configuration |
| ------------------------------------------------------------ | --------------------------------------------------------- | ------------------------------------------------------------ |
| root<br/> FolderA<br/> **File1.csv**<br/> File2.json<br/> Subfolder1<br/> **File3.csv**<br/> File4.json<br/> **File5.csv**<br/> Metadata<br/> FileListToCopy.txt | File1.csv<br>Subfolder1/File3.csv<br>Subfolder1/File5.csv | **In the dataset:**<br>- Folder path: `root/FolderA`<br><br>**In the Copy activity source:**<br>- File list path: `root/Metadata/FileListToCopy.txt` <br><br>The file list path points to a text file in the same data store that includes a list of files you want to copy (one file per line, with the relative path to the path configured in the dataset). |
## Use DistCp to copy data from HDFS
[DistCp](https://hadoop.apache.org/docs/current3/hadoop-distcp/DistCp.html) is a Hadoop native command-line tool for doing a distributed copy in a Hadoop cluster. When you run a command in DistCp, it first lists all the files to be copied and then creates several Map jobs in the Hadoop cluster. Each Map job does a binary copy from the source to the sink.
The Copy activity supports using DistCp to copy files as is into Azure Blob storage (including [staged copy](copy-activity-performance.md)) or an Azure data lake store. In this case, DistCp can take advantage of your cluster's power instead of running on the self-hosted integration runtime. Using DistCp provides better copy throughput, especially if your cluster is very powerful. Based on the configuration, the Copy activity automatically constructs a DistCp command, submits it to your Hadoop cluster, and monitors the copy status.
### Prerequisites
To use DistCp to copy files as is from HDFS to Azure Blob storage (including staged copy) or the Azure data lake store, make sure that your Hadoop cluster meets the following requirements:
* The MapReduce and YARN services are enabled.
* YARN version is 2.5 or later.
* The HDFS server is integrated with your target data store: **Azure Blob storage** or **Azure Data Lake Store (ADLS Gen1)**:
- Azure Blob FileSystem is natively supported since Hadoop 2.7. You need only to specify the JAR path in the Hadoop environment configuration.
- Azure Data Lake Store FileSystem is packaged starting from Hadoop 3.0.0-alpha1. If your Hadoop cluster version is earlier than that version, you need to manually import Azure Data Lake Store-related JAR packages (azure-datalake-store.jar) into the cluster from [here](https://hadoop.apache.org/releases.html), and specify the JAR file path in the Hadoop environment configuration.
* Prepare a temp folder in HDFS. This temp folder is used to store a DistCp shell script, so it will occupy KB-level space.
* Make sure that the user account that's provided in the HDFS linked service has permission to:
* Submit an application in YARN.
* Create a subfolder and read/write files under the temp folder.
### Configurations
For DistCp-related configurations and examples, go to the [HDFS as source](#hdfs-as-source) section.
## Use Kerberos authentication for the HDFS connector
There are two options for setting up the on-premises environment to use Kerberos authentication for the HDFS connector. You can choose the one that better fits your situation.
* Option 1: [Join a self-hosted integration runtime machine in the Kerberos realm](#kerberos-join-realm)
* Option 2: [Enable mutual trust between the Windows domain and the Kerberos realm](#kerberos-mutual-trust)
For either option, make sure you turn on webhdfs for Hadoop cluster:
1. Create the HTTP principal and keytab for webhdfs.
> [!IMPORTANT]
> The HTTP Kerberos principal must start with "**HTTP/**" according to Kerberos HTTP SPNEGO specification. Learn more from [here](https://hadoop.apache.org/docs/current/hadoop-project-dist/hadoop-hdfs/WebHDFS.html#HDFS_Configuration_Options).
```bash
Kadmin> addprinc -randkey HTTP/<namenode hostname>@<REALM.COM>
Kadmin> ktadd -k /etc/security/keytab/spnego.service.keytab HTTP/<namenode hostname>@<REALM.COM>
```
2. HDFS configuration options: add the following three properties in `hdfs-site.xml`.
```xml
<property>
<name>dfs.webhdfs.enabled</name>
<value>true</value>
</property>
<property>
<name>dfs.web.authentication.kerberos.principal</name>
<value>HTTP/_HOST@<REALM.COM></value>
</property>
<property>
<name>dfs.web.authentication.kerberos.keytab</name>
<value>/etc/security/keytab/spnego.service.keytab</value>
</property>
```
### <a name="kerberos-join-realm"></a>Option 1: Join a self-hosted integration runtime machine in the Kerberos realm
#### Requirements
* The self-hosted integration runtime machine needs to join the Kerberos realm and canβt join any Windows domain.
#### How to configure
**On the KDC server:**
Create a principal, and specify the password.
> [!IMPORTANT]
> The username should not contain the hostname.
```bash
Kadmin> addprinc <username>@<REALM.COM>
```
**On the self-hosted integration runtime machine:**
1. Run the Ksetup utility to configure the Kerberos Key Distribution Center (KDC) server and realm.
The machine must be configured as a member of a workgroup, because a Kerberos realm is different from a Windows domain. You can achieve this configuration by setting the Kerberos realm and adding a KDC server by running the following commands. Replace *REALM.COM* with your own realm name.
```cmd
C:> Ksetup /setdomain REALM.COM
C:> Ksetup /addkdc REALM.COM <your_kdc_server_address>
```
After you run these commands, restart the machine.
2. Verify the configuration with the `Ksetup` command. The output should be like:
```cmd
C:> Ksetup
default realm = REALM.COM (external)
REALM.com:
kdc = <your_kdc_server_address>
```
**In your data factory or Synapse workspace:**
* Configure the HDFS connector by using Windows authentication together with your Kerberos principal name and password to connect to the HDFS data source. For configuration details, check the [HDFS linked service properties](#linked-service-properties) section.
### <a name="kerberos-mutual-trust"></a>Option 2: Enable mutual trust between the Windows domain and the Kerberos realm
#### Requirements
* The self-hosted integration runtime machine must join a Windows domain.
* You need permission to update the domain controller's settings.
#### How to configure
> [!NOTE]
> Replace REALM.COM and AD.COM in the following tutorial with your own realm name and domain controller.
**On the KDC server:**
1. Edit the KDC configuration in the *krb5.conf* file to let KDC trust the Windows domain by referring to the following configuration template. By default, the configuration is located at */etc/krb5.conf*.
```config
[logging]
default = FILE:/var/log/krb5libs.log
kdc = FILE:/var/log/krb5kdc.log
admin_server = FILE:/var/log/kadmind.log
[libdefaults]
default_realm = REALM.COM
dns_lookup_realm = false
dns_lookup_kdc = false
ticket_lifetime = 24h
renew_lifetime = 7d
forwardable = true
[realms]
REALM.COM = {
kdc = node.REALM.COM
admin_server = node.REALM.COM
}
AD.COM = {
kdc = windc.ad.com
admin_server = windc.ad.com
}
[domain_realm]
.REALM.COM = REALM.COM
REALM.COM = REALM.COM
.ad.com = AD.COM
ad.com = AD.COM
[capaths]
AD.COM = {
REALM.COM = .
}
```
After you configure the file, restart the KDC service.
2. Prepare a principal named *krbtgt/REALM.COM\@AD.COM* in the KDC server with the following command:
```cmd
Kadmin> addprinc krbtgt/REALM.COM@AD.COM
```
3. In the *hadoop.security.auth_to_local* HDFS service configuration file, add `RULE:[1:$1@$0](.*\@AD.COM)s/\@.*//`.
**On the domain controller:**
1. Run the following `Ksetup` commands to add a realm entry:
```cmd
C:> Ksetup /addkdc REALM.COM <your_kdc_server_address>
C:> ksetup /addhosttorealmmap HDFS-service-FQDN REALM.COM
```
2. Establish trust from the Windows domain to the Kerberos realm. [password] is the password for the principal *krbtgt/REALM.COM\@AD.COM*.
```cmd
C:> netdom trust REALM.COM /Domain: AD.COM /add /realm /password:[password]
```
3. Select the encryption algorithm that's used in Kerberos.
a. Select **Server Manager** > **Group Policy Management** > **Domain** > **Group Policy Objects** > **Default or Active Domain Policy**, and then select **Edit**.
b. On the **Group Policy Management Editor** pane, select **Computer Configuration** > **Policies** > **Windows Settings** > **Security Settings** > **Local Policies** > **Security Options**, and then configure **Network security: Configure Encryption types allowed for Kerberos**.
c. Select the encryption algorithm you want to use when you connect to the KDC server. You can select all the options.
:::image type="content" source="media/connector-hdfs/config-encryption-types-for-kerberos.png" alt-text="Screenshot of the "Network security: Configure encryption types allowed for Kerberos" pane":::
d. Use the `Ksetup` command to specify the encryption algorithm to be used on the specified realm.
```cmd
C:> ksetup /SetEncTypeAttr REALM.COM DES-CBC-CRC DES-CBC-MD5 RC4-HMAC-MD5 AES128-CTS-HMAC-SHA1-96 AES256-CTS-HMAC-SHA1-96
```
4. Create the mapping between the domain account and the Kerberos principal, so that you can use the Kerberos principal in the Windows domain.
a. Select **Administrative tools** > **Active Directory Users and Computers**.
b. Configure advanced features by selecting **View** > **Advanced Features**.
c. On the **Advanced Features** pane, right-click the account to which you want to create mappings and, on the **Name Mappings** pane, select the **Kerberos Names** tab.
d. Add a principal from the realm.
:::image type="content" source="media/connector-hdfs/map-security-identity.png" alt-text="Screenshot of the "Security Identity Mapping" pane":::
**On the self-hosted integration runtime machine:**
* Run the following `Ksetup` commands to add a realm entry.
```cmd
C:> Ksetup /addkdc REALM.COM <your_kdc_server_address>
C:> ksetup /addhosttorealmmap HDFS-service-FQDN REALM.COM
```
**In your data factory or Synapse workspace:**
* Configure the HDFS connector by using Windows authentication together with either your domain account or Kerberos principal to connect to the HDFS data source. For configuration details, see the [HDFS linked service properties](#linked-service-properties) section.
## Lookup activity properties
For information about Lookup activity properties, see [Lookup activity](control-flow-lookup-activity.md).
## Delete activity properties
For information about Delete activity properties, see [Delete activity](delete-activity.md).
## Legacy models
>[!NOTE]
>The following models are still supported as is for backward compatibility. We recommend that you use the previously discussed new model, because the authoring UI has switched to generating the new model.
### Legacy dataset model
| Property | Description | Required |
|:--- |:--- |:--- |
| type | The *type* property of the dataset must be set to *FileShare* |Yes |
| folderPath | The path to the folder. A wildcard filter is supported. Allowed wildcards are `*` (matches zero or more characters) and `?` (matches zero or a single character); use `^` to escape if your actual file name has a wildcard or this escape character inside. <br/><br/>Examples: rootfolder/subfolder/, see more examples in [Folder and file filter examples](#folder-and-file-filter-examples). |Yes |
| fileName | The name or wildcard filter for the files under the specified "folderPath". If you don't specify a value for this property, the dataset points to all files in the folder. <br/><br/>For filter, allowed wildcards are `*` (matches zero or more characters) and `?` (matches zero or a single character).<br/>- Example 1: `"fileName": "*.csv"`<br/>- Example 2: `"fileName": "???20180427.txt"`<br/>Use `^` to escape if your actual folder name has a wildcard or this escape character inside. |No |
| modifiedDatetimeStart | Files are filtered based on the attribute *Last Modified*. The files are selected if their last modified time is greater than or equal to `modifiedDatetimeStart` and less than `modifiedDatetimeEnd`. The time is applied to the UTC time zone in the format *2018-12-01T05:00:00Z*. <br/><br/> Be aware that the overall performance of data movement will be affected by enabling this setting when you want to apply a file filter to large numbers of files. <br/><br/> The properties can be NULL, which means that no file attribute filter is applied to the dataset. When `modifiedDatetimeStart` has a datetime value but `modifiedDatetimeEnd` is NULL, it means that the files whose last modified attribute is greater than or equal to the datetime value are selected. When `modifiedDatetimeEnd` has a datetime value but `modifiedDatetimeStart` is NULL, it means that the files whose last modified attribute is less than the datetime value are selected.| No |
| modifiedDatetimeEnd | Files are filtered based on the attribute *Last Modified*. The files are selected if their last modified time is greater than or equal to `modifiedDatetimeStart` and less than `modifiedDatetimeEnd`. The time is applied to the UTC time zone in the format *2018-12-01T05:00:00Z*. <br/><br/> Be aware that the overall performance of data movement will be affected by enabling this setting when you want to apply a file filter to large numbers of files. <br/><br/> The properties can be NULL, which means that no file attribute filter is applied to the dataset. When `modifiedDatetimeStart` has a datetime value but `modifiedDatetimeEnd` is NULL, it means that the files whose last modified attribute is greater than or equal to the datetime value are selected. When `modifiedDatetimeEnd` has a datetime value but `modifiedDatetimeStart` is NULL, it means that the files whose last modified attribute is less than the datetime value are selected.| No |
| format | If you want to copy files as is between file-based stores (binary copy), skip the format section in both the input and output dataset definitions.<br/><br/>If you want to parse files with a specific format, the following file format types are supported: *TextFormat*, *JsonFormat*, *AvroFormat*, *OrcFormat*, *ParquetFormat*. Set the *type* property under format to one of these values. For more information, see the [Text format](supported-file-formats-and-compression-codecs-legacy.md#text-format), [JSON format](supported-file-formats-and-compression-codecs-legacy.md#json-format), [Avro format](supported-file-formats-and-compression-codecs-legacy.md#avro-format), [ORC format](supported-file-formats-and-compression-codecs-legacy.md#orc-format), and [Parquet format](supported-file-formats-and-compression-codecs-legacy.md#parquet-format) sections. |No (only for binary copy scenario) |
| compression | Specify the type and level of compression for the data. For more information, see [Supported file formats and compression codecs](supported-file-formats-and-compression-codecs-legacy.md#compression-support).<br/>Supported types are: *Gzip*, *Deflate*, *Bzip2*, and *ZipDeflate*.<br/>Supported levels are: *Optimal* and *Fastest*. |No |
>[!TIP]
>To copy all files under a folder, specify **folderPath** only.<br>To copy a single file with a specified name, specify **folderPath** with folder part and **fileName** with file name.<br>To copy a subset of files under a folder, specify **folderPath** with folder part and **fileName** with wildcard filter.
**Example:**
```json
{
"name": "HDFSDataset",
"properties": {
"type": "FileShare",
"linkedServiceName":{
"referenceName": "<HDFS linked service name>",
"type": "LinkedServiceReference"
},
"typeProperties": {
"folderPath": "folder/subfolder/",
"fileName": "*",
"modifiedDatetimeStart": "2018-12-01T05:00:00Z",
"modifiedDatetimeEnd": "2018-12-01T06:00:00Z",
"format": {
"type": "TextFormat",
"columnDelimiter": ",",
"rowDelimiter": "\n"
},
"compression": {
"type": "GZip",
"level": "Optimal"
}
}
}
}
```
### Legacy Copy activity source model
| Property | Description | Required |
|:--- |:--- |:--- |
| type | The *type* property of the Copy activity source must be set to *HdfsSource*. |Yes |
| recursive | Indicates whether the data is read recursively from the subfolders or only from the specified folder. When recursive is set to *true* and the sink is a file-based store, an empty folder or subfolder will not be copied or created at the sink.<br/>Allowed values are *true* (default) and *false*. | No |
| distcpSettings | The property group when you're using HDFS DistCp. | No |
| resourceManagerEndpoint | The YARN Resource Manager endpoint | Yes, if using DistCp |
| tempScriptPath | A folder path that's used to store the temp DistCp command script. The script file is generated and will be removed after the Copy job is finished. | Yes, if using DistCp |
| distcpOptions | Additional options are provided to DistCp command. | No |
| maxConcurrentConnections | The upper limit of concurrent connections established to the data store during the activity run. Specify a value only when you want to limit concurrent connections.| No |
**Example: HDFS source in Copy activity using DistCp**
```json
"source": {
"type": "HdfsSource",
"distcpSettings": {
"resourceManagerEndpoint": "resourcemanagerendpoint:8088",
"tempScriptPath": "/usr/hadoop/tempscript",
"distcpOptions": "-m 100"
}
}
```
## Related content
For a list of data stores that are supported as sources and sinks by the Copy activity, see [supported data stores](copy-activity-overview.md#supported-data-stores-and-formats).
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