The SFTP Connector transfers files to and from a remote SFTP server.
Each SFTP Connector connects uploads to a specified folder and downloads from a set of folders on the remote SFTP server.
Files that reach the SFTP Connector in the CData Arc flow are uploaded to the upload target folder, and files found in the download target folder(s) are downloaded and entered into the Arc flow. The connector supports upload and download filters to only send and receive specified file names and/or file extensions.
This section contains all of the configurable connector properties.
Settings related to establishing the connection to the remote SFTP host.
- Connector Id The static, unique identifier for the connector.
- Connector Description An optional field to provide a free-form description of the connector and its role in the flow.
- Remote Host The hostname or IP address of the SFTP server.
- Remote Port The port on which to connect to the SFTP server.
Settings related to authenticating to the SFTP server.
- Authentication Mode The type of authentication to use with the SFTP server.
- User The username for logging in to the SFTP server.
- Password The password for logging in to the SFTP server.
- Client Certificate The certificate with a private key to use during public key authentication. Only available when Authentication Mode is set to Public Key or Multi-Factor Authentication. Optionally, you can use the Create Certificate button to create a new certificate.
- Certificate Password The password required to access the Client Certificate.
Setting related to verifying the SFTP server’s identity.
- Server Thumbprint The thumbprint of the certificate that identifies the SFTP server. You can also set this to a certificate file containing the server’s public key. When you test the connection, the connector prompts you to accept/trust the thumbprint presented by the server.
Setting related to uploading files to the SFTP server.
- Remote Path Files processed by the connector are uploaded to this remote folder.
Settings related to downloading from the SFTP server.
- Remote Path The remote folder from which files are downloaded. Use a comma-delimited list to specify multiple paths.
- File Mask A glob pattern that determines which files in the Remote Path should be downloaded (for example, *.txt).
- Delete files (after received) Check this to delete successfully downloaded files from the SFTP server.
Settings related to caching and comparing files between multiple downloads.
- File Size Comparison Check this to keep a record of downloaded file names and sizes. Previously downloaded files are skipped unless the file size is different than the last download.
- Timestamp Comparison Check this to keep a record of downloaded file names and last-modified timestamps. Previously downloaded files are skipped unless the timestamp is different than the last download.
Settings related to the automatic processing of files by the connector.
- Upload Whether files arriving at the connector should automatically be uploaded.
- Retry Interval The number of minutes before a failed upload is retried.
- Max Attempts The maximum number of times the connector processes the input file. Success is measured based on a successful server acknowledgement. If you set this to 0, the connect retries the file indefinitely.
- Download Whether the connector should automatically poll the remote download path(s) for files to download.
- Download Interval The interval between automatic download attempts.
- Minutes Past the Hour The minutes offset for an hourly schedule. Only applicable when the interval setting above is set to Hourly. For example, if this value is set to 5, the automation service downloads at 1:05, 2:05, 3:05, etc.
- Time The time of day that the attempt should occur. Only applicable when the interval setting above is set to Daily, Weekly, or Monthly.
- Day The day on which the attempt should occur. Only applicable when the interval setting above is set to Weekly or Monthly.
- Minutes The number of minutes to wait before attempting the download. Only applicable when the interval setting above is set to Minute.
- Cron Expression A five-position string representing a cron expression that determines when the attempt should occur. Only applicable when the interval setting above is set to Advanced.
Settings related to the allocation of resources to the connector.
- Max Workers The maximum number of worker threads consumed from the threadpool to process files on this connector. If set, this overrides the default setting on the Settings > Automation page.
- Max Files The maximum number of files sent by each thread assigned to the connector. If set, this overrides the default setting on the Settings > Automation page.
These options allow you to execute custom commands on the remote server at various times during connector execution.
- After Connect Execute this command directly after connecting.
- After Get Execute this command after downloading each file.
- After Put Execute this command after uploading each file.
- Before Get Execute this command before downloading each file.
- Before Put Execute this command before uploading each file.
Note: During processing, the macros %SourceFilename% and %SourceFilenameNoExt% resolve to the name of the current file and the name of the current file without an extension.
Example: After downloading, you need to move each file from the download folder to a History subfolder. Use the After Get field to supply the
The available commands are described below:
onerror: Pass the
failargument to instruct the connector to treat errors that come from the custom scripts as errors for the overall transaction. Wthout
failthe connector logs any exceptions and continues processing.
cd: Change directory.
mkdir: Create directory.
move: Rename or move file.
rm: Delete or remove file.
rmdir: Remove directory.
These are a collection of settings that identify and authenticate to the proxy through which the SFTP connection should be routed. By default, this section uses the global settings on the Settings Page. Clear the checkbox to supply settings specific to your SFTP connector.
- Proxy Type The protocol used by a proxy-based firewall.
- Proxy Host The name or IP address of a proxy-based firewall.
- Proxy Port The TCP port for a proxy-based firewall.
- Proxy User The user name to use to authenticate with a proxy-based firewall.
- Proxy Password A password used to authenticate to a proxy-based firewall.
- Authentication Scheme Leave the default None or choose from one of the following authentication schemes: Basic, Digest, Proprietary, or NTLM.
Settings not included in the previous categories.
- Connection Pooling Check this to have the connector utilize a pool to access and store connections. This is useful in scenarios where the server places restrictions on the frequency of logon attempts.
- Download Excluded Extensions A comma-delimited list of file extensions that should not be downloaded by the connector.
- Download Excluded Prefixes A comma-delimited list of prefixes that instructs the connector not to download filenames that begin with a specified prefix.
- Max Download Files The maximum number of files to be downloaded from the SFTP server in one polling interval. Set to -1 to allow all files to be downloaded.
- Minimum File Size The minimum file size to process. If a file being uploaded is smaller than the specified size, it is finalized as Skipped. For files being downloaded, the connector adds a transaction log entry indicating that the file was skipped because of its size.
- Monitor File Growth Check this to have the application store the file sizes of the remote files between polling intervals, and only download files that do not change in size. This prevents the connector from downloading files that are still in the process of being written on the server.
- Processing Delay The amount of time (in seconds) by which the processing of files placed in the Input folder is delayed. This is a legacy setting. Best practice is to use a File connector to manage local file systems instead of this setting.
- Recurse Check this to download files in subfolders of the target remote path. The subdirectories are preserved for the received files.
- Resume Downloads If enabled, when an error occurs during a file download, the connector stores the portion of the file that was downloaded and attempts to download the remainder of the file on the next download attempt.
- Resume Uploads If enabled, when an error occurs during a file upload, the connector notes the number of bytes that were transferred and attempts to upload the remainder of the file on the next upload attempt.
- SSH Encryption Algorithms A comma-delimited list of algorithms to use during SSH encryption. By default, all algorithms are enabled. Arc supports the following algorithms:
aes256-ctr, aes256-cbc, aes192-ctr, aes192-cbc, aes128-ctr, aes128-cbc, 3des-ctr, 3des-cbc, cast128-cbc, blowfish-cbc, arcfour, arcfour128, arcfour256, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org
- Local File Scheme A filemask for determining local file names as they are downloaded by the connector. You can use the following macros to reference contextual information:
%ConnectorId%, %Filename%, %FilenameNoExt%, %Ext%, %ShortDate%, %LongDate%, %RegexFilename:%, %DateFormat:%.
For example: %FilenameNoExt%_%ShortDate%%Ext%
- Receive Filter A glob pattern filter to determine which files should be downloaded from the remote storage (for example, *.txt). You can use negative patterns to indicate files that should not be downloaded (for example, -*.tmp). Use this setting when you need multiple File Mask patterns. Multiple patterns can be separated by commas, with later filters taking priority except when an exact match is found.
- Temp Download Extension A temporary file extension to append to file downloads while the transfer is in progress.
- Temp Upload Extension A temporary file extension to append to file uploads while the transfer is in progress.
- Temp Upload Prefix A temporary file prefix to prepend to file uploads while the transfer is in progress.
- Temp Upload Path A temporary path on the remote SFTP server where files are uploaded. The file is moved into the permanent upload path after the transfer is complete.
- Timeout The duration the connector waits for a connection response before throwing a timeout error.
- Wait for Channel Close Check this to have the conector wait for the server to close the SSH channel before disconnecting. If timeouts occur during the logoff sequence, you should disable this setting.
- Save to Sent Folder Check this to copy files processed by the connector to the Sent folder for the connector.
- Sent Folder Scheme Instructs the connector to group messages in the Sent folder according to the selected interval. For example, the Weekly option instructs the connector to create a new subfolder each week and store all messages for the week in that folder. The blank setting tells the connector to save all messages directly in the Sent folder. For connectors that process many messages, using subfolders helps keep messsages organized and improves performance.
- Log Level The verbosity of logs generated by the connector. When you request support, set this to Debug.
- Log Subfolder Scheme Instructs the connector to group files in the Logs folder according to the selected interval. For example, the Weekly option instructs the connector to create a new subfolder each week and store all logs for the week in that folder. The blank setting tells the connector to save all logs directly in the Logs folder. For connectors that process many transactions, using subfolders helps keep logs organized and improves performance.
- Log Messages Check this to have the log entry for a processed file include a copy of the file itself. If you disable this, you might not be able to download a copy of the file from the Input or Output tabs.
Miscellaneous settings are for specific use cases.
- Other Settings Enables you to configure hidden connector settings in a semicolon-separated list (for example,
setting1=value1;setting2=value2). Normal connector use cases and functionality should not require the use of these settings.
Establishing a Connection
The following settings are required to connect to a remote SFTP server:
- Remote Host
- Remote Port
- Authentication Mode
- Password or Client Certificate/Certificate Password
- Server Thumbprint
When testing the connection to the server, the connector prompts you to accept/trust the thumbprint of the server’s public key.
The SFTP Connector uploads files from the Input/Send Folder that match the Send Filter set on the Advanced tab. Files are automatically uploaded to the SFTP server if Upload Automation is enabled in the connector.
Remote Path should be set to the folder on the remote SFTP server where files should be uploaded. The application changes directories to the specified folder after logging in to the server.
If any files could not be uploaded, the connector attempts to send them again after Retry Interval minutes have elapsed. This process continues until the Max Attempts setting is reached, after which the connector raises an error and the file is longer sent automatically.
Downloaded files are displayed in the Output/Receive Folder of the connector, or passed along to the next connector in the flow. Files are automatically downloaded from the SFTP server if Download Automation is enabled in the connector, and can be manually downloaded by clicking the Receive button on the Output tab.
Remote Path should be set to the folder on the remote SFTP server from which files should be downloaded. The application changes directories to the specified folder after logging in to the server. The File Mask property filters files so that only filenames matching the glob pattern are downloaded from the server.
You can use the Delete files (after download) setting to delete the files on the remote server after successfully downloading them. On the Output tab, click the Receive button to test the settings and retrieve the matching files from the server.
If Recurse is checked on the Advanced tab, when receiving a file from the Remote Path in the SFTP connector:
- The message for the file that is received contains a Subfolder header in its metadata.
- This header contains the subfolder, relative to the Remote Path in the SFTP connector, that the file was received from.
- This subfolder header is supported by other connectors that support a subfolder header in Send operations.
When sending files, if a Subfolder header is present on the message that is sent to the Upload Path in the SFTP connector:
- The file is placed in the subfolder, relative to the Upload Path in the SFTP connector, that is specified in the subfolder header.
- The subfolder is created if permissions are available.