Proxmox Backup

ZFS is a combined file system and logical volume manager used to provide enterprise-grade storage features on budget hardware. It is highly recommended for Proxmox Backup Server environments due to its data protection and performance capabilities.

Key Features:

• Data Integrity: Protection against data corruption, self-healing, and continuous integrity checking.
• Storage Efficiency: Data compression at the file system level, snapshots, and copy-on-write clones.
• Redundancy: Supports various RAID levels including RAID0, RAID1, RAID10, RAIDZ-1, RAIDZ-2, and RAIDZ-3.
• Performance: Support for SSD caching and asynchronous network replication.
• Security: Built-in encryption.

Note: ZFS modules are included in the packages; manual compilation is not required.

The proxmox-backup-client is a command-line tool that acts as a client for Proxmox Backup Server. It allows users to connect to backup servers to perform two primary categories of tasks:

1. Management Commands: Issuing commands to manage the server and its resources.
2. Backup and Restore Operations: Creating new backups of data and restoring existing backups from the server.

Proxmox Backup Server provides several enterprise-grade features for data protection:

• Deduplication & Incremental Backups: Minimizes storage usage and network impact by only storing and transferring unique data deltas.
• Data Integrity: Uses SHA-256 checksums to ensure backup accuracy.
• Compression: Utilizes ultra-fast Zstandard compression.
• Encryption: Supports client-side encryption using AES-256 GCM (Authenticated Encryption). All client-server communication is secured via TLS.
• Remote Sync: Efficiently synchronizes data to remote sites by transferring only new data deltas.
• Tape Backup: Provides support for long-term archiving to tape and tape library management.
• Ransomware Protection: Achieved through fine-grained access control, integrity verification, and off-site synchronization/tape backups.

Proxmox Backup Server uses several specific configuration files to manage different aspects of the service. The following files are used for configuration:

• acl.cfg: Access Control Lists and roles.
• datastore.cfg: Datastore definitions and options.
• domains.cfg: Domain configurations.
• media-pool.cfg: Media pool settings.
• notifications.cfg: Notification settings.
• notifications-priv.cfg: Private notification settings.
• tape.cfg: Tape drive configurations.
• tape-job.cfg: Tape job definitions.
• user.cfg: User management and options.
• remote.cfg: Remote endpoint configurations.
• sync.cfg: Synchronization job settings.
• verification.cfg: Data verification settings.

The Proxmox Backup Server ecosystem consists of the following core components:

• Server-daemon: Provides a RESTful API, manages asynchronous tasks, collects usage statistics, and handles scheduling.
• JavaScript management web interface: A web-based UI for managing the server.
• proxmox-backup-manager: A CLI tool used for managing the server itself.
• proxmox-backup-client: A CLI tool used by clients (in any Linux amd64 environment) to interact with the server and perform backups/restores.

A Datastore is a location where backups are stored. In the current implementation, a datastore is a directory within a standard Unix filesystem (such as ext4, xfs, or zfs).

Key Characteristics

• Identification: Datastores are identified by a unique ID (or name).
• Configuration: Datastore configuration is stored in /etc/proxmox-backup/datastore.cfg.
• Filesystem Requirements: The underlying filesystem must support at least 65,538 subdirectories per directory. This is required to accommodate the 2^16 pre-created chunk namespace directories plus the . and .. entries. Filesystems like ext3 or ext4 with dir_nlink disabled may not be supported.
• Retention & Maintenance: Each datastore can have its own retention settings (hourly, daily, weekly, monthly, yearly), pruning schedules, and garbage collection (GC) schedules.

The web interface is organized into three main functional areas:

1. Header: Located at the top. It displays version information and provides access to documentation, running task monitoring, language settings, display configurations, and the logout button.
2. Sidebar: Located on the left. This is the primary navigation menu containing administration options and management categories.
3. Configuration Panel: Located in the center. This area displays the specific control interfaces and settings corresponding to the item selected in the Sidebar.

Authentication realms are configured using a specific header format: <realm-type>: <name>. Each realm is followed by its specific configuration options.

Common realm types include openid and ldap.

Note for LDAP: The LDAP bind password is not stored directly in the realm configuration file; it is stored in ldap_passwords.json.

openid: master
  client-id pbs
  comment
  issuer-url http://192.168.0.10:8080/realms/master
  username-claim username

ldap: ldap-server
  base-dn OU=People,DC=ldap-server,DC=example,DC=com
  mode ldaps
  server1 192.168.0.10
  sync-attributes email=mail
  sync-defaults-options enable-new=0,remove-vanished=acl;entry
  user-attr uid
  user-classes inetorgperson,posixaccount,person,user