Storware Backup & Recovery supports backup for OpenStack:

  • Disk attachment through Cinder with changed block tracking (preferred):

    • supports all hypervisors and storages

    • supports incremental backup

    • proxy VM is required - used for the disk attachment process.

  • Disk image transfer - for KVM hypervisors with VMs using QCOW2

  • Volumes or Ceph-based storage:

    • supports incremental backup

    • disk images are transferred directly from API (no Proxy VM required)

  • Disk attachment through Cinder:

    • supports all hypervisors and storages

    • no incremental backup

    • proxy VM is required - used for the disk attachment process.

Backup Strategies

Libvirt strategy

Storware Backup & Recovery supports OpenStack environments that use KVM hypervisors and VMs running on QCOW2 or RAW files. Storware Backup & Recovery communicates with OpenStack APIs such as Nova and Glance to collect metadata and for the import of the restored process. However, the actual backup is done over SSH directly from the hypervisor. The process is exactly the same as in Deployment in the KVM/Xen environment. Storware Backup & Recovery Node can be installed anywhere - it just needs to have access to the OpenStack APIs and hypervisor SSH via a network. Both full and incremental backups are supported.

Backup Process

  • direct access to the hypervisor over SSH

  • crash-consistent snapshot taken directly using virsh (QCOW2/RAW file), rbd snapshot for Ceph (separate call for each storage backend)

  • optional application consistency using pre/post snapshot command execution • QCOW2/RAW-file data exported over SSH (optionally with netcat)

  • Ceph RBD data exported using rbd export or RBD-NBD when incremental is used

  • metadata exported from OpenStack APIs (nova, glance, cinder)

  • the last snapshot kept on the hypervisor for the next incremental backup (if at least one schedule assigned to the VM has backup type set to incremental)

  • restore recreates files/volumes according to their backend (same transfer mechanism as used in backup) and then defines VM on the hypervisor

Disk attachment

Storware Backup & Recovery also supports the disk-attachment method using cinder. This should allow you to use cinder-compatible storage and still allow Storware Backup & Recovery to create backups. Incremental backup is supported in disk attachment changed block tracking (which has higher CPU overhead). Storware Backup & Recovery needs to communicate OpenStack service's API to attach drives to the proxy VM with Storware Backup & Recovery Node installed.

Backup Process

  • crash-consistent snapshot using cinder API

  • optional application consistency using pre/post snapshot command execution

  • metadata exported from API

  • volumes created from snapshotted disks are mounted one by one to the Proxy VM

  • data read directly on the Proxy VM

  • incremental backups supported for Ceph RBD - a list of the changed blocks are fetched from the monitors, and only these blocks are read from the attached disk on the Proxy VM

  • if an instance is created from the glance image and "download image from glance" option is enabled data is downloaded from glance API, an instance is created from the instance metadata, and the images which are fetched from the glance API

  • restore creates empty disks on the Proxy VM, imports merged data then recreates the VM using these volumes, it will try to use the image from a glance if present in the target environment or it will upload the image to the glance and register it with the restored VM

Ceph RBD storage backend

Storware Backup & Recovery also supports deployments with Ceph RBD as a storage backend. Storware Backup & Recovery communicates directly with Ceph monitors using RBD export/RBD-NBD when used with the Libvirt strategy or - when used with the Disk-attachment method - only during incremental backups (snapshot difference).

Libvirt strategy

Disk attachment strategy

Storware Backup & Recovery supports OpenStack with Ceph RBD volumes. Here is an example of a typical (expected) section that needs to be added in cinder.conf for Ceph in the OpenStack environment:

volume_backend_name = rbd
volume_driver = cinder.volume.drivers.rbd.RBDDriver
rbd_pool = volumes
rbd_ceph_conf = /etc/ceph/ceph.conf
rbd_flatten_volume_from_snapshot = false
rbd_max_clone_depth = 5
rbd_store_chunk_size = 4
rados_connect_timeout = -1
glance_api_version = 2
rbd_user = volumes
rbd_secret_uuid = ce6d1549-4d63-476b-afb6-88f0b196414f

A good article on how to set up Ceph with OpenStack can be found here.

To set up the Openstack HVM with Ceph RBD volumes in Storware Backup & Recovery:

  1. Add Ceph storage as described here

  2. Add the hypervisor manager as described here.

  3. Go to Virtual Environments -> Infrastructure -> Clusters and select cluster that is used by Openstack.

  1. In Storage Provider field select previously added Ceph storage.

Now you can save and sync the inventory - if Ceph communication works properly you should be able to see Hypervisor Storage entries (in Hypervisors -> Storage tab) representing your Ceph storage pools.

QCOW2 files on NFS storage

Example: scenario QCOW2 files residing on NFS

You can configure the NFS volume backend here:

Make sure the QCOW2 volumes are enabled.

For an NFS backend, it's recommended to set these values in /etc/cinder/cinder.conf:

default_volume_type = nfs
nfs_sparsed_volumes = true
nfs_qcow2_volumes = true
volume_driver = cinder.volume.drivers.nfs.NfsDriver
enabled_backends = nfs

Nova volumes

Storware Backup & Recovery is able to backup nova volumes using libvirt strategy. In the hypervisor manager settings there is an option Download image from glance. When this option is enabled the original image from glance is downloaded. If it is disabled, then the image is not downloaded, however the nova volume created from it is backed up.

Adding hypervisor managers

When creating the hypervisor manager, provide the following data in the fields:

URL - Keystone API URL, e.g.

Authentication domain:

  • name - name of domain

  • domainId - optional domain id

  • user - OpenStack user.

  • password - password for that user.

  • default project - name of default project in domain.

Scope VMs to Domain - you can create one or more Authentication Domains based on this setting, as described in the Authentication Domains section below.

Download image from a glance - allows Storware Backup & Recovery to use images from a glance as described in the disk attachment strategy

When you index the hypervisor manager, make sure you provide the correct SSH credentials for each hypervisor that appeared on the Hypervisors tab. You can also use SSH public key authentication.

Note: When restoring the instances, make sure that the provided user is a member of the target tenant.

Authentication Domains

Storware Backup & Recovery supports OpenStack environments with multiple domains. Each OpenStack Hypervisor Manager needs to have at least one Authentication Domain provided.

Storware Backup & Recovery supports two types of domain authorization:

  • Unscoped - single credentials to multiple domains

  • Scoped - single credentials to single domain

Single credentials to single domain

Scoping VMs to Domain option needs to be turned on.

In that setup user can create Authentication Domains for every Domain in OpenStack environment. Projects and Virtual Machines are only scanned in provided Authentication Domains.

Single credentials to multiple domains

Scoping VMs to Domain option needs to be turned off.

In that setup user need to create only one Authentication Domain. Projects and Virtual Machines are scanned in every domain that provided user has access to.

Openstack tags

To list tags for specific instance:

root@c254:~# nova show d6787375-ea0c-49fd-878b-35b71747c62a |grep tags
| tags                                 | ["test"]

Tags for Openstack requires nova API version >= 2.26.

Openstack Access Keys

During Inventory Synchronization, Storware Backup & Recovery scans all Keypairs (to which a user has access) and stores them as Access Keys. When restoring an instance, the user can specify the Access Key.

Note: If the access key selected for restore is no longer present in the Openstack environment, it will be restored.

Openstack Flavor

During Inventory Synchronization, Storware Backup & Recovery scans all Flavors and saves their configuration. When restoring an instance, the user can specify the flavor.

Note: If the flavor selected for restore is no longer present in the Openstack environment, it will be restored with the same configuration and availability as the original flavor.


  • Storware Backup & Recovery does not backup and restores keypairs that user used in Storware Backup & Recovery doesn't have access to. The restored instance will have no keypairs assigned. In such a case, the keypairs have to be backed up and restored manually under the same name before restoring the instance.

  • For the libvirt strategy only, QCOW2/RAW files or Ceph RBD are supported as the backend.

  • The disk attachment method with Ceph requires access to the monitors from the Proxy VM.

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