qubes-doc/BackupEmergencyRestoreV3.md

5.0 KiB

layout title permalink
doc Emergency Backup Recovery - format version 3 /doc/BackupEmergencyRestoreV3/

Emergency Backup Recovery without Qubes - format version 3

This page describes how to perform emergency restore of backup created on Qubes R2 or later (which uses backup format 3).

The Qubes backup system has been designed with emergency disaster recovery in mind. No special Qubes-specific tools are required to access data backed up by Qubes. In the event a Qubes system is unavailable, you can access your data on any GNU/Linux system with the following procedure.

Note: In the following example, the backup file is assumed to be both encrypted and compressed.

  1. Untar the main backup file.

    [user@restore ~]$ tar -i -xvf qubes-backup-2013-12-26-123456 backup-header backup-header.hmac qubes.xml.000 qubes.xml.000.hmac vm1/private.img.000 vm1/private.img.000.hmac vm1/icon.png.000 vm1/icon.png.000.hmac vm1/firewall.xml.000 vm1/firewall.xml.000.hmac vm1/whitelisted-appmenus.list.000 vm1/whitelisted-appmenus.list.000.hmac dom0-home/dom0user.000 dom0-home/dom0user.000.hmac

  2. Verify the integrity of the backup-header file contains basic information about your backup. [user@restore ~]$ cd vm1/ [user@restore ~]$ openssl dgst -sha512 -hmac "your_passphrase" backup-header HMAC-SHA512(backup-header)= 5b266783e116fe3b2601a54c249ca5f5f96d421dfe6828eeaeb2dcd014e9e945c27b3d7b0f952f5d55c927318906d9c360f387b0e1f069bb8195e96543e2969c [user@restore ~]$ cat backup-header.hmac (stdin)= 5b266783e116fe3b2601a54c249ca5f5f96d421dfe6828eeaeb2dcd014e9e945c27b3d7b0f952f5d55c927318906d9c360f387b0e1f069bb8195e96543e2969c

Note: The hash values should match. If they do not match, then the backup file may have been tampered with, or there may have been a storage error.

Note: If your backup was hashed with a message digest algorithm other than sha512, you must substitute the correct message digest command. A complete list of supported message digest algorithms can be found with openssl list-message-digest-algorithms.

  1. Read the backup-header. You'll need some of this information later. The file will look similar to this: version=3 hmac-algorithm=SHA512 crypto-algorithm=aes-256-cbc encrypted=True compressed=True

If you see version=2 here, go to Emergency Backup Recovery - format version 2 page instead.

  1. Verify the integrity of the private.img file which houses your data.

    [user@restore ~]$ cd vm1/ [user@restore vm1]$ openssl dgst -sha512 -hmac "your_passphrase" private.img.000 HMAC-SHA512(private.img.000)= cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e [user@restore vm1]$ cat private.img.000.hmac (stdin)= cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e

Note: The hash values should match. If they do not match, then the backup file may have been tampered with, or there may have been a storage error.

Note: If your backup was hashed with a message digest algorithm other than sha512, you must substitute the correct message digest command. A complete list of supported message digest algorithms can be found with openssl list-message-digest-algorithms. You can check backup-header file for the hash used to create the backup.

  1. Decrypt the private.img file.

    cat private.img.??? | openssl enc -d -pass pass:your_passphrase -aes-256-cbc -out private.img.dec

Note: If your backup was encrypted with a cipher algorithm other than aes-256-cbc, you must substitute the correct cipher command. A complete list of supported cipher algorithms can be found with openssl list-cipher-algorithms. You can check backup-header file to get that information.

  1. Decompress the decrypted private.img file.

    [user@restore vm1]$ zforce private.img.dec [user@restore vm1]$ gunzip private.img.dec.gz

Note: If your backup was compressed with a program other than gzip, you must substitute the correct compression program. backup-header file contains name of program used to compress the data.

  1. Untar the decrypted and decompressed private.img file.

    [user@restore vm1]$ tar -xvf private.img.dec vm1/private.img

  2. Mount the private.img file and access your data.

    [user@restore vm1]$ sudo mkdir /mnt/img [user@restore vm1]$ sudo mount -o loop vm1/private.img /mnt/img/ [user@restore vm1]$ cat /mnt/img/home/user/your_data.txt This data has been successfully recovered!

Note: You may wish to store a plain text copy of these instructions with your Qubes backups in the event that you fail to recall the above procedure while this web page is inaccessible. You may obtain a plaintext version of this file in Git repository housing all the documentation at:

https://github.com/QubesOS/qubes-doc.git