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Vera Crypt

Backup VeraCrypt using Urbackup.

VC container file incremental backup

In result this is not incremental backup. Every backup is a full backup, but only changes are transferred.

Setup

Example client setup:

  • Windows Client
  • Dedicated NTFS partition (32GB)
  • VC container file on dedicated NTFS partition (10GB file)
    • encrypted empty space looks like data, so empty VC container is using 10GB of data on 32GB disc.

Urbackup client:

  • set to image backup of whole NTFS drive (partition).

Urbackup server:

  • Backup storagae on BTRS file system
  • Image backup storage set to Raw copy-on-write file” (COW)

Results

  • Urbackup clients can handle NTFS file system during image backup so only used area is backed up
    • for first backup (full backup), 10GB was transferred.
  • Urbackup server tracks hashes of block on disc to detect only changed blocks so only changed blocks are transferred
  • Urbackup server creates 32GB .raw file for each image backup. This file can be mount as normal disc using loop device.
    • Urbackup server is using sparse files, so only 10GB of filesystem is used for 32GB image file.
  • Urbackup server is using BTRFS CoW (Copy-on-Write) filesystem with all its benefits, so:
    • every next backup is a reflink-copy of previous one (it points to the same data), and only changed blocks are modified
      • so with our example setup next backup create new directory with 32GB .raw file, but it only takes few MB more data on BTRS.
    • There is no real incremential backups chain. There is no risk of loosing one element from chain. Every backup looks like full backup - 32GB .raw file with full disc image is present. No need to refresh full backup every n-th backup. It is possible too keep unfinished number of incremental backups without risk.