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#!/usr/bin/env python # -*- coding: utf-8 -*- # # Copyright (c) 2017 Red Hat, Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # import logging import os import time import uuid import ovirtsdk4 as sdk import ovirtsdk4.types as types logging.basicConfig(level=logging.DEBUG, filename='example.log') # This example shows how the virtual machine backup process. # The connection details: API_URL = 'https://engine40.example.com/ovirt-engine/api' API_USER = 'admin@internal' API_PASSWORD = 'redhat123' # The file containing the certificat of the CA used by the server. In # an usual installation it will be in the file '/etc/pki/ovirt-engine/ca.pem'. API_CA_FILE = 'ca.pem' # The name of the application, to be used as the 'origin' of events # sent to the audit log: APPLICATION_NAME = 'mybackup' # The name of the virtual machine that contains the data that we # want to back-up: DATA_VM_NAME = 'myvm' # The name of the virtual machine where we will attach the disks in # order to actually back-up them. This virtual machine will usually have # some kind of back-up software installed. AGENT_VM_NAME = 'myagent' # Connect to the server: connection = sdk.Connection( url=API_URL, username=API_USER, password=API_PASSWORD, ca_file=API_CA_FILE, debug=True, log=logging.getLogger(), ) logging.info('Connected to the server.') # Get the reference to the root of the services tree: system_service = connection.system_service() # Get the reference to the service that we will use to send events to # the audit log: events_service = system_service.events_service() # In order to send events we need to also send unique integer ids. These # should usually come from an external database, but in this example we # will just generate them from the current time in seconds since Jan 1st # 1970. event_id = int(time.time()) # Get the reference to the service that manages the virtual machines: vms_service = system_service.vms_service() # Find the virtual machine that we want to back up. Note that we need to # use the 'all_content' parameter to retrieve the retrieve the OVF, as # it isn't retrieved by default: data_vm = vms_service.list( search='name=%s' % DATA_VM_NAME, all_content=True, )[0] logging.info( 'Found data virtual machine \'%s\', the id is \'%s\'.', data_vm.name, data_vm.id, ) # Find the virtual machine were we will attach the disks in order to do # the backup: agent_vm = vms_service.list( search='name=%s' % AGENT_VM_NAME, )[0] logging.info( 'Found agent virtual machine \'%s\', the id is \'%s\'.', agent_vm.name, agent_vm.id, ) # Find the services that manage the data and agent virtual machines: data_vm_service = vms_service.vm_service(data_vm.id) agent_vm_service = vms_service.vm_service(agent_vm.id) # Create an unique description for the snapshot, so that it is easier # for the administrator to identify this snapshot as a temporary one # created just for backup purposes: snap_description = '%s-backup-%s' % (data_vm.name, uuid.uuid4()) # Send an external event to indicate to the administrator that the # backup of the virtual machine is starting. Note that the description # of the event contains the name of the virtual machine and the name of # the temporary snapshot, this way, if something fails, the administrator # will know what snapshot was used and remove it manually. events_service.add( event=types.Event( vm=types.Vm( id=data_vm.id, ), origin=APPLICATION_NAME, severity=types.LogSeverity.NORMAL, custom_id=event_id, description=( 'Backup of virtual machine \'%s\' using snapshot \'%s\' is ' 'starting.' % (data_vm.name, snap_description) ), ), ) event_id += 1 # Save the OVF to a file, so that we can use to restore the virtual # machine later. The name of the file is the name of the virtual # machine, followed by a dash and the identifier of the virtual machine, # to make it unique: ovf_data = data_vm.initialization.configuration.data ovf_file = '%s-%s.ovf' % (data_vm.name, data_vm.id) with open(ovf_file, 'w') as ovs_fd: ovs_fd.write(ovf_data.encode('utf-8')) logging.info('Wrote OVF to file \'%s\'.', os.path.abspath(ovf_file)) # Send the request to create the snapshot. Note that this will return # before the snapshot is completely created, so we will later need to # wait till the snapshot is completely created. # The snapshot will not include memory. Change to True the parameter # persist_memorystate to get it (in that case the VM will be paused for a while). snaps_service = data_vm_service.snapshots_service() snap = snaps_service.add( snapshot=types.Snapshot( description=snap_description, persist_memorystate=False, ), ) logging.info( 'Sent request to create snapshot \'%s\', the id is \'%s\'.', snap.description, snap.id, ) # Poll and wait till the status of the snapshot is 'ok', which means # that it is completely created: snap_service = snaps_service.snapshot_service(snap.id) while snap.snapshot_status != types.SnapshotStatus.OK: logging.info( 'Waiting till the snapshot is created, the satus is now \'%s\'.', snap.snapshot_status, ) time.sleep(1) snap = snap_service.get() logging.info('The snapshot is now complete.') # Retrieve the descriptions of the disks of the snapshot: snap_disks_service = snap_service.disks_service() snap_disks = snap_disks_service.list() # Attach all the disks of the snapshot to the agent virtual machine, and # save the resulting disk attachments in a list so that we can later # detach them easily: attachments_service = agent_vm_service.disk_attachments_service() attachments = [] for snap_disk in snap_disks: attachment = attachments_service.add( attachment=types.DiskAttachment( disk=types.Disk( id=snap_disk.id, snapshot=types.Snapshot( id=snap.id, ), ), active=True, bootable=False, interface=types.DiskInterface.VIRTIO, ), ) attachments.append(attachment) logging.info( 'Attached disk \'%s\' to the agent virtual machine.', attachment.disk.id, ) # Now the disks are attached to the virtual agent virtual machine, we # can then ask that virtual machine to perform the backup. Doing that # requires a mechanism to talk to the backup software that runs inside the # agent virtual machine. That is outside of the scope of the SDK. But if # the guest agent is installed in the virtual machine then we can # provide useful information, like the identifiers of the disks that have # just been attached. for attachment in attachments: if attachment.logical_name is not None: logging.info( 'Logical name for disk \'%s\' is \'%s\'.', attachment.disk.id, attachment.logicalname, ) else: logging.info( 'The logical name for disk \'%s\' isn\'t available. Is the ' 'guest agent installed?', attachment.disk.id, ) # Insert here the code to contact the backup agent and do the actual # backup ... logging.info('Doing the actual backup ...') # Detach the disks from the agent virtual machine: for attachment in attachments: attachment_service = attachments_service.attachment_service(attachment.id) attachment_service.remove() logging.info( 'Detached disk \'%s\' to from the agent virtual machine.', attachment.disk.id, ) # Remove the snapshot: snap_service.remove() logging.info('Removed the snapshot \'%s\'.', snap.description) # Send an external event to indicate to the administrator that the # backup of the virtual machine is completed: events_service.add( event=types.Event( vm=types.Vm( id=data_vm.id, ), origin=APPLICATION_NAME, severity=types.LogSeverity.NORMAL, custom_id=event_id, description=( 'Backup of virtual machine \'%s\' using snapshot \'%s\' is ' 'completed.' % (data_vm.name, snap_description) ), ), ) event_id += 1 # Close the connection to the server: connection.close() (责任编辑：IT) |