> For the complete documentation index, see [llms.txt](https://docs.pentaho.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.pentaho.com/pdia-data-integration/9.3-data-integration/data-integration-perspective-in-the-pdi-client/advanced-topics-pdi-perspective/pdi-run-modifiers/parameters/vfs-properties/specifying-vfs-properties-as-parameters.md).
# Specifying VFS properties as parameters
VFS properties can be specified as [parameters](/pdia-data-integration/9.3-data-integration/data-integration-perspective-in-the-pdi-client/advanced-topics-pdi-perspective/pdi-run-modifiers/parameters.md). The format of the reference to a VFS property is **vfs.scheme.property.host**.
The following list describes the subparts of the format:
* The **vfs** subpart is required to identify this as a virtual file system configuration property.
* The **scheme** subpart represents the VFS driver's scheme (or VFS type), such as HTTP, SFTP, or ZIP.
* The **property** subpart is the name of a VFS driver's ConfigBuilder's setter (the specific VFS element that you want to set).
* The **host** optionally defines a specific IP address or hostname that this setting applies to.
You must consult each scheme's API reference to determine which properties you can create variables for. Apache provides VFS scheme documentation at . The **org.apache.commons.vfs.provider** package lists each of the configurable VFS providers (FTP, HTTP, SFTP, etc.). Each provider has a **FileSystemConfigBuilder** class that in turn has **set\*(FileSystemOptions, Object)** methods. If a method's second parameter is a **String** or a **number** (Integer, Long, etc.) then you can create a PDI variable to set the value for VFS dialog boxes.
The table below explains VFS properties for the SFTP scheme. Each property must be declared as a PDI variable and preceded by the `vfs.sftp` prefix as defined above.
| SFTP VFS Property | Purpose |
| ------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| **compression** | Specifies whether ZLIB compression is used for the destination files. Possible values are `zlib` and `none`. |
| **identity** | The private key file (fully qualified local or remote path and filename) to use for host authentication. |
| **authkeypassphrase** | The passphrase for the private key specified by the **identity** property. |
| **StrictHostKeyChecking** | If this is set to `no`, the certificate of any remote host will be accepted. If set to `yes`, the remote host must exist in the known hosts file (`~/.ssh/known_hosts`). |
**Note:** All of these properties are optional.
The following examples show how to specify parameters as VFS properties:
---
# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.
## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.
Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:
```
GET https://docs.pentaho.com/pdia-data-integration/9.3-data-integration/data-integration-perspective-in-the-pdi-client/advanced-topics-pdi-perspective/pdi-run-modifiers/parameters/vfs-properties/specifying-vfs-properties-as-parameters.md?ask=&goal=
```
`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.