Understanding crash-consistent and application-consistent backups
When protecting virtual machines agentlessly using the Rapid Snap for Virtual feature, the data in the backup snapshots you capture can be in one of two states:
-
Crash-consistent. At minimum, all agentless backups captured by the Rapid Recovery Core are crash-consistent. The backup is a snapshot in time of all the data and operating system files on each protected volume, at the time those files were captured. If you restore from a crash-consistent recovery point, the VM OS starts and can read and understand the file system, and all files in it.
If you recover a transactional application from a crash-consistent state, the database returns to the last valid state. That most recent valid state may be from the time of the crash, or it may be from earlier than the crash. If it is from earlier, then the database must roll forward some work to make the data files match the information in the logs. This process takes some time when you first open the database, which causes a delay when starting up the machine.
- Application-consistent. Application-consistent backups use Microsoft's Volume Shadow Copy Service (VSS) to ensure the consistency of application data when a shadow copy is created. Using VSS writers, pending input/output operations are completed and log files committed prior to snapshots being captured. As a result, if you restore from an application-consistent recovery point, the VM OS starts and can read and understand the file system. Additionally, files for transactional applications such as SQL Server or Exchange are in a consistent state. For example, SQL Server logs match the data files, and the database opens quickly without needing any repairs.
Support for Hyper-V guest cluster
Rapid Recovery can protect shared virtual hard disks in the VHDX format on a Hyper-V host by using agentless protection.
|
|
NOTE: Rapid Recovery does not support protection of shared VHD sets. |
A shared VHDX is a virtual hard disk on a Hyper-V host that is shared among a cluster of guests. When the Agent is installed on the Hyper-V host for agentless — or host-based — protection, protects the shared VHDXs at the host level. can also protect a shared VHDX at the guest level when the Agent is installed on the guest.
When you select and protect the virtual machines (VMs) available on the host, protects all virtual hard disks associated with those VMs, including any shared VHDXs. After protection is complete, you can edit the protection schedule and remove or protect shared VHDXs at the host level under Volumes on the Summary page for the host. All recovery points of these shared virtual hard disks are displayed on the Recovery Points tab for the host, not for the individual VMs.
When using agentless protection, automatically detects new VHDXs and offers the option to protect them. Unprotected disks are displayed in a separate Shared Disks section. Metadata is not gathered for these disks until after they are protected.
On the Summary page for a guest virtual machine, shared VHDXs are listed under Shared Volumes. A clickable icon next to the volume name opens a dialog that displays the VMs that are connected to that disk. If a connected VM is not protected, then the option to protect that VM is available.
Understanding the Rapid Recovery Agent software installer
You can download installers from the Rapid Recovery Core. From the Downloads page on the Core Console, you can choose to download the Agent Installer, the Local Mount Utility (LMU), or an SNMP MIB file For more information about SNMP, see Understanding SNMP settings.
|
|
NOTE: For access to the Agent Installer, see Downloading the Rapid Recovery Agent Installer. For more information about deploying the Agent Installer, see the Rapid Recovery Installation and Upgrade Guide. |
The Agent installer is used to install the Rapid Recovery Agent application on machines that are intended to be protected by the Rapid Recovery Core. If you determine that you have a machine that requires the Agent Installer, you can download the web installer from the Downloads page of the Rapid Recovery Core Console.
|
|
NOTE: You can download the Core, Agent, and other Rapid Recovery software from the QorePortal. Log into the QorePortal at https://qoreportal.quest.com/ and click Settings, and then click |
Downloading the Rapid Recovery Agent Installer
Download the Rapid Recovery Agent Installer and deploy it to any machine that you want to protect on the Rapid Recovery Core. Complete the steps in this procedure to download the installer.
- To download the Agent installer directly from the machine you want to protect, do the following:
- In a web browser, open the QorePortal at https://qoreportal.quest.com/.
- Click Settings, and then click
Downloads.
- Under Applications, locate Agent Software. If you want a full Windows 64-bit installer, click Full Installer. To download a smaller package that streams the latest version of the installer over the web, click Web Installer.
The installer file, for example
Agent-X64-6.3.xxxx.exe, saves to the downloads destination folder.
- To download the web installer from the Core, on the Core Console icon bar, click the
More icon and then select
Downloads.
- On the Downloads page, from the Agent pane, click Download web installer.
- If prompted, from the Opening Agent-Web.exe dialog box, click Save File.
The installer file, for example
Agent-X64-6.3.xxxx.exe, saves to the downloads destination folder. - Move the installer to the appropriate machine and install the Rapid Recovery Agent software.
For more information about installing the Rapid Recovery Agentsoftware, see the Rapid Recovery 6.4 Installation and Upgrade Guide.