**Caution:** The Qubes R3.2 backup system currently relies on a [weak key derivation scheme](https://github.com/QubesOS/qubes-issues/issues/971).
Although resolved in R4.0 and higher with the switch to scrypt, it is *strongly recommended* that users select a *high-entropy* passphrase for use with Qubes backups.
As of Qubes R2B3, these functions are integrated into the Qubes VM Manager GUI.
There are also two command-line tools available which perform the same functions: [qvm-backup](/doc/dom0-tools/qvm-backup/) and [qvm-backup-restore](/doc/dom0-tools/qvm-backup-restore/).
If you wish to send your backup to a [USB mass storage device](/doc/usb/), you can use the directory selection widget to mount a connected device (under "Other locations" item on the left); or first mount the device in a VM, then select the mount point inside that VM as the backup destination.
You must also specify a directory on the device or in the VM, or a command to be executed in the VM as a destination for your backup.
For example, if you wish to send your backup to the `~/backups` folder in the target VM, you would simply browse to it using the convenient directory selection dialog (`...`) at the right.
This destination directory must already exist.
If it does not exist, you must create it manually prior to backing up.
By specifying the appropriate directory as the destination in a VM, it is possible to send the backup directly to, e.g., a USB mass storage device attached to the VM.
Likewise, it is possible to enter any command as a backup target by specifying the command as the destination in the VM.
This can be used to send your backup directly to, e.g., a remote server using SSH.
**Warning: Saving the settings will result in your backup passphrase being saved in plaintext in dom0, so consider your threat model before checking this box.**
If you wish to send your backup to a [USB mass storage device](/doc/usb/), you can use the directory selection widget to mount a connected device (under "Other locations" item on the left); or first mount the device in a VM, then select the mount point inside that VM as the backup destination.
You must also specify a directory on the device or in the VM, or a command to be executed in the VM as a destination for your backup.
For example, if you wish to send your backup to the `~/backups` folder in the target VM, you would simply browse to it using the convenient directory selection dialog (`...`) at the right.
If it does not exist, you must create it manually prior to backing up.
By specifying the appropriate directory as the destination in a VM, it is possible to send the backup directly to, e.g., a USB mass storage device attached to the VM.
Likewise, it is possible to enter any command as a backup target by specifying the command as the destination in the VM.
This can be used to send your backup directly to, e.g., a remote server using SSH.
**Note:** The supplied passphrase is used for **both** encryption/decryption and integrity verification.
If you decide not to encrypt your backup (by unchecking the **Encrypt backup** box), the passphrase you supply will be used **only** for integrity verification.
If you supply a passphrase but do not check the **Encrypt backup** box, your backup will **not** be encrypted!
You must also specify the directory and filename of the backup (or a command to be executed in a VM) in the **Backup file** field.
If you followed the instructions in the previous section, "Creating a Backup," then your backup is most likely in the location you chose as the destination in step 3.
For example, if you had chosen the `~/backups` directory of a VM as your destination in step 3, you would now select the same VM and again browse to (using `...`) the `backups` folder.
Once you've located the backup file, double-click it or select it and hit **OK**.
1.**ignore missing templates and net VMs**: If any of the VMs in your backup depended upon a NetVM or TemplateVM that is not present in (i.e., "missing from") the current system, checking this box will ignore the fact that they are missing and restore the VMs anyway and set them to use the default NetVM and system default template.
2.**ignore username mismatch**: This option applies only to the restoration of dom0's home directory.
If your backup was created on a Qubes system which had a different dom0 username than the dom0 username of the current system, then checking this box will ignore the mismatch between the two usernames and proceed to restore the home directory anyway.
3.**Verify backup integrity, do not restore the data**: This will scan the backup file for corrupted data.
However, it does not currently detect if it is missing data as long as it is a correctly structured, non-corrupted backup file.
See [issue #3498](https://github.com/QubesOS/qubes-issues/issues/3498) for more details.
You must also specify the directory and filename of the backup (or a command to be executed in a VM) in the **Backup file** field.
If you followed the instructions in the previous section, "Creating a Backup," then your backup is most likely in the location you chose as the destination in step 3.
For example, if you had chosen the `~/backups` directory of a VM as your destination in step 3, you would now select the same VM and again browse to (using `...`) the `backups` folder.
Once you've located the backup file, double-click or select it and hit **OK**.
1.**ignore missing**: If any of the VMs in your backup depended upon a NetVM, ProxyVM, or TemplateVM that is not present in (i.e., "missing from") the current system, checking this box will ignore the fact that they are missing and restore the VMs anyway and set them to use the default NetVM and system default template.
2.**ignore username mismatch**: This option applies only to the restoration of dom0's home directory.
If your backup was created on a Qubes system which had a different dom0 username than the dom0 username of the current system, then checking this box will ignore the mismatch between the two usernames and proceed to restore the home directory anyway.
3.**Verify backup integrity, do not restore the data**: This will scan the backup file for corrupted data.
However, it does not currently detect if it is missing data as long as it is a correctly structured, non-corrupted backup file. See [issue #3498](https://github.com/QubesOS/qubes-issues/issues/3498) for more details.
In order to migrate your Qubes system from one physical machine to another, simply follow the backup procedure on the old machine, [install Qubes](/downloads/) on the new machine, and follow the restoration procedure on the new machine.
* If you plan to store the backup for a long time or on third-party servers, you should make sure to use a very long, high-entropy passphrase.
(Depending on the decryption passphrase you use for your system drive, this may necessitate selecting a stronger passphrase.
If your system drive decryption passphrase is already sufficiently strong, it may not.)
* An adversary who has access to your backups may try to substitute one backup for another.
For example, when you attempt to retrieve a recent backup, the adversary may instead give you a very old backup containing a compromised VM.
If you're concerned about this type of attack, you may wish to use a different passphrase for each backup, e.g., by appending a number or date to the passphrase.
* If you're forced to enter your system drive decryption passphrase in plain view of others (where it can be shoulder-surfed), then you may want to use a different passphrase for your backups (even if your system drive decryption passphrase is already maximally strong).
On the other hand, if you're careful to avoid shoulder-surfing and/or have a passphrase that's difficult to detect via shoulder-surfing, then this may not be a problem for you.
* The Qubes R3.2 and earlier backup system relies on `openssl enc`, which is known to use a very weak key derivation scheme.
The Qubes backup system also uses the same passphrase for authentication and for encryption, which is problematic from a security perspective.
Users are advised to use a very high entropy passphrase for Qubes backups.
For a full discussion, see [this ticket](https://github.com/QubesOS/qubes-issues/issues/971) and [this thread](https://groups.google.com/d/msg/qubes-devel/CZ7WRwLXcnk/u_rZPoVxL5IJ).
