---
title: "DAF Files & DupArchive Extraction Tool"
url: https://phatdev.net/en/docs/sl-migrations/how-to-work-with-daf-files-and-the-duparchive-extraction-tool
lang: en
updated: 2026-10-20
alternate:
  vi: https://phatdev.net/docs/sl-migrations/how-to-work-with-daf-files-and-the-duparchive-extraction-tool
markdown: https://phatdev.net/en/docs/sl-migrations/how-to-work-with-daf-files-and-the-duparchive-extraction-tool.md
---

# DAF Files & DupArchive Extraction Tool

Part of the doc set: [SL Migrations](https://phatdev.net/en/docs/sl-migrations.md)

> The .daf format: its structure, how the installer extracts it, and a note on command-line tools.

## DAF Files & Extraction Tool

`.daf` (DupArchive Format) is the archive format of the DupArchive engine. Unlike ZIP, the archive is written and read in small blocks, each with its own hash → it supports resuming after an interruption and has no size limit like ZipArchive on older PHP builds.

## Structure

```
[Header]
  - Flags (compression, encryption) and format version
[Entries, one after another]
  - Folder: path, permissions, modification time
  - File: path, size, hash
          + content blocks (each block has its own hash)
```

## Extraction

The supported way is to open `installer.php` on the destination server: the installer reads the archive in small batches over AJAX, calls the next batch by itself and can continue after an interruption. See [Classic Install](https://phatdev.net/en/docs/sl-migrations/classic-install).

> Note: the current SL Migrations build ships no dedicated command-line extraction tool for `.daf` (there is no `duparchive-extract.phar`, and no `--list`, `--info`, `--verify` or `--extract-file` flags). To extract manually from the command line, build a **ZIP** archive (ZipArchive or Shell Exec engine) and follow [Two-Part Install](https://phatdev.net/en/docs/sl-migrations/two-part-install).

## Integrity check

Every content block in a `.daf` has its own hash, and the installer checks it while reading. If the archive is damaged or was not fully uploaded, the extraction step reports an error on the affected file; download the archive again from the source or from a backup and run it again.

## See also

- [Two-Part Install](https://phatdev.net/en/docs/sl-migrations/two-part-install)
- [Zip engines](https://phatdev.net/en/docs/sl-migrations/how-to-work-with-the-different-zip-engines)