kvm.full_backup_info

This method is only available when using RVC version 3.13.0 or later.

Describe a full backup archive without extracting it and without affecting the virtual machine. Only the leading members of the archive are read, so the method returns in under a second even for large archives, compressed or not.

The result describes the file itself, how and when the backup was taken, the virtual machine as its saved definition describes it, its firmware (NVRAM and vTPM), and the members of the archive. For archives created before RVC 3.13.0, virtual_machine and firmware are null. For more about what an archive contains, see kvm.full_backup.

JSON-RPC Request

{"jsonrpc":"2.0","id":1,"method":"kvm.full_backup_info","params":{"filename":"<backup_file_path>"}}

Request Parameters

Argument	Type	Description	Required
`filename`	String	The path to the backup file.	Yes

JSON-RPC Response

{
    "jsonrpc": "2.0",
    "id": 1,
    "result": {
        "file": {"name": "<file_name>", "path": "<backup_file_path>", "size": "<bytes>", "modified": "<timestamp>", "compressed": "<boolean>"},
        "backup": {"format": "<format>", "rvc": "<rvc_version>", "vm": "<kvm_hostname>", "host": "<node_hostname>", "created": "<timestamp>", "optimized": "<boolean>", "compressed": "<boolean>", "automatic": "<boolean>", "cluster_managed": "<boolean>", "uncompressed_size": "<bytes>", "disk_path": "<disk_path>", "disk_virtual_size": "<bytes>", "disk_cluster_size": "<bytes>", "files": ["<archive_member>"]},
        "virtual_machine": {"name": "<kvm_hostname>", "uuid": "<uuid>", "arch": "<arch>", "machine": "<machine_type>", "firmware": "<firmware>", "vcpus": "<vcpus>", "memory": "<bytes>", "clock": "<clock>", "boot": ["<boot_device>"], "video": "<video_model>", "guest_agent": "<boolean>", "disks": [], "interfaces": [], "graphics": [], "host_devices": []},
        "firmware": {
            "type": "<firmware>",
            "secure_boot": "<boolean>",
            "nvram": {"path": "<nvram_path>", "member": "<archive_member>", "size": "<bytes>", "in_backup": "<boolean>", "secure_boot_enable": "<boolean>", "keys": {"pk": "<bytes>", "kek": "<bytes>", "db": "<bytes>", "dbx": "<bytes>"}},
            "vtpm": {"state_path": "<vtpm_state_path>", "in_backup": "<boolean>", "certificates": []}
        },
        "members": [
            {"name": "<archive_member>", "size": "<bytes>"}
        ]
    }
}

Response parameters

Parameter	Type	Description
`file`	Object	The name and size of the backup file, and whether it is compressed.
`backup`	Object	How, when, and where the backup was taken, as recorded in the archive's `backup.metadata` file.
`virtual_machine`	Object	The virtual machine as described by the definition saved in the archive. `null` for archives created before RVC 3.13.0.
`firmware`	Object	The VM's firmware type and Secure Boot setting, and whether its NVRAM store and vTPM state are in the archive. For a VM that uses neither UEFI nor a vTPM, only `type` and `secure_boot` are returned. `null` for archives created before RVC 3.13.0.
`members`	Array	The name and size of each member of the archive, in archive order.

In RVC 3.13.0, the CLI output for an archive created before RVC 3.13.0 shows 0.0 for the fields the archive does not carry, such as the disk size and cluster size, instead of leaving them empty. The JSON response also reports the size of the backup.metadata member as 2 bytes smaller than it is.

RVC CLI Example

rvc kvm full-backup-info --filename /mnt/backups/kvm1-backup-1.tar

Response

kvm1-backup-1.tar  17.2G
taken 2026-09-18T14:57:26Z from kvm1 on sit0001red0, RVC 3.13.0

Backup
  Format             3
  Host Versions      libvirt 11.3.0, QEMU 10.0.2
  Taken By           request
  Disk               /kvm/kvm1/disk0.qcow2
  Disk Size          17.2G on disk, 79.6G as the guest sees it
  Disk Cluster Size  524k
  Optimized          no
  Cluster Managed    yes

Virtual Machine
  Name    kvm1
  Type    kvm on pc-q35-10.0 (x86_64)
  CPU     1 vCPU
  Memory  1.07G
  Boot    hd, network

Firmware
  Firmware    uefi, Secure Boot enforced
  NVRAM       /kvm/kvm1/nvram/OVMF_VARS.fd
              in this backup
              Secure Boot turned on in the variables
  Keys        pk 1005B, kek 4071B, db 6133B, dbx 20716B
  TPM         emulator 2.0 at /kvm/kvm1/swtpm
              in this backup

Contents
  backup.metadata        1.27k
  xml/vm/vm.xml          5.58k
  xml/vm/vm.ini          680
  nvram/OVMF_VARS.fd     541k
  swtpm/tpm2-00.permall  8.85k
  disk0.qcow2            17.2G