ZBackup
What ZBackup is
ZBackup is free, self-hosted backup software for Linux that performs global deduplication, keeping repeated data regions only once. It accepts almost any file data through standard input, including archives, proprietary formats, and raw disk images, then restores through standard output. Deduplication works with uncompressed, unencrypted input. LZMA compression is the default, with optional LZO, and AES-128 encryption is available in CBC mode with PKCS#7 padding. SHA256 checks run during backup creation and restoration; restoration fails when the check differs. Repository files are immutable, so new backups do not modify or delete existing files. ZBackup does not transfer data over a network itself; repositories can be copied with rsync or file-storing cloud tools. It is listed for Debian, Ubuntu, Arch Linux, Fedora/EPEL, and FreeBSD. Known block hashes stay in memory, which may limit very large repositories, and retrieving one file requires restoring the complete backup.
Who it suits
ZBackup suits Linux users wanting self-hosted, deduplicated backups and control over repository storage. It can handle varied file formats and supports command-line input and output workflows.
What it does well
- Global deduplication stores repeated regions once
- Accepts archives, proprietary formats, and raw disk images
- LZMA default with optional LZO compression
- SHA256 checks verify creation and restoration
- Immutable repository files preserve existing backups
What to know first
- No built-in network transfer facility
- Large repositories may hit in-memory hash limits
- Retrieving one file requires full restoration
- Deduplication needs uncompressed, unencrypted input
Verdict
ZBackup provides a free Linux backup workflow with broad input support, compression, encryption, integrity checks, and immutable repositories. Its storage-transfer and file-retrieval limitations matter for large or frequently selective restores.
Facts from ZBackup's own pages
- Backup scope
- mixed · github.com, 20 Sept 2026
- Compression
- It supports LZMA compression by default and optional LZO compression. · zbackup.org, 12 Oct 2026
- Computer backup
- Yes · github.com, 20 Sept 2026
- Encryption
- It supports AES-128 encryption in CBC mode with PKCS#7 padding. · zbackup.org, 12 Oct 2026
- Free plan
- Yes · github.com, 20 Sept 2026
- Immutable repository files
- During backup, it creates new files and does not modify or delete existing repository files. · zbackup.org, 12 Oct 2026
- Input and restore
- It accepts data through standard input and restores backups through standard output. · zbackup.org, 12 Oct 2026
- Input formats
- It accepts virtually any file data, including archives, proprietary formats, and raw disk images. · github.com, 12 Oct 2026
- Input limitation
- For deduplication to work, input data should be uncompressed and unencrypted. · github.com, 12 Oct 2026
- Integrity checks
- It checks backup data with SHA256 when creating and restoring backups, and fails if the restore check does not match. · zbackup.org, 12 Oct 2026
- License
- The project is licensed under GNU GPL version 2 or later, with OpenSSL. · github.com, 12 Oct 2026
- Linux availability
- The site says ZBackup is included in Debian, Ubuntu, and Arch Linux distributions. · zbackup.org, 12 Oct 2026
- Mobile backup
- No · github.com, 20 Sept 2026
- Supported platforms
- linux · github.com, 20 Sept 2026
- Purpose
- ZBackup is a globally deduplicating backup tool that stores repeated data regions only once. · github.com, 12 Oct 2026
- Ransomware protection
- No · github.com, 20 Sept 2026
- Repository behavior
- Repository files are immutable, so backups create new files without modifying existing ones. · github.com, 12 Oct 2026
- Repository memory use
- ZBackup keeps known block hashes in an in-memory table, which can create scalability limits for large repositories. · zbackup.org, 12 Oct 2026
- Restore limitation
- A backup must be fully restored to access a required file; the site says there is no quick file selection option. · zbackup.org, 12 Oct 2026
- Restore modes
- file · github.com, 20 Sept 2026
- Scalability limit
- The program keeps hashes of known blocks in an in-memory hash table, which may cause scalability problems for very large repositories. · github.com, 12 Oct 2026
- Storage integrations
- It has no built-in network transfer facility; the site says users can copy the repository with rsync or use cloud storage that stores files. · zbackup.org, 12 Oct 2026
- Storage workflow
- ZBackup does not send backups over the network itself; the repository can be copied using rsync or a cloud storage tool. · github.com, 12 Oct 2026
- Support
- The project points users to its Google Groups discussion forum for help. · github.com, 12 Oct 2026
Where ZBackup stands on Freedom251
- Backup software#91 of 151