Backup & Recovery for VMware Environments with Avamar 6.0

Transcription

1 White Paper Backup & Recovery for VMware Environments with Avamar 6.0 A Detailed Review Abstract With the ever increasing pace of virtual environments deployed in the enterprise cloud, the requirements for protecting these environments is quickly being identified as the bottleneck to deployment expansion. This white paper highlights several new features within EMC Avamar 6.0 that specifically target and greatly advance the capabilities and performance of VMware data protection. With these features, EMC Avamar is enabling the rapid continued expansion of cloud environments, required by the demand for IT-as-a-Service (ITaaS) October 2011

2 Copyright 2011 EMC Corporation. All Rights Reserved. EMC believes the information in this publication is accurate of its publication date. The information is subject to change without notice. The information in this publication is provided as is. EMC Corporation makes no representations or warranties of any kind with respect to the information in this publication, and specifically disclaims implied warranties of merchantability or fitness for a particular purpose. Use, copying, and distribution of any EMC software described in this publication requires an applicable software license. For the most up-to-date listing of EMC product names, see EMC Corporation Trademarks on EMC.com. VMware is a registered trademark of VMware, Inc. All other trademarks used herein are the property of their respective owners. Part Number h8945 2

3 Table of Contents Executive summary... 4 Audience... 4 Introduction... 5 Avamar: Efficient Data Protection for VMware Environments Guest-level Backup & Restore... 6 Image-level Backup & Restore... 7 VM Data Protection Management: Avamar vcenter Integration... 9 Conclusion References

4 Executive summary IT backup administrators face many challenges as they witness virtual cloud environments growing exponentially, and no aspect can pose greater difficulty to this growth than in the area of backup and recovery. While virtualization technology optimizes the use of the physical resources on a physical server basis, ultimately the underlying resources and applications available to efficiently protect these environments can limit planned expansion from a data protection manageability perspective. Today s virtual environments typically contain hundreds if not thousands of VMs. With the lower amount of VMs as we have seen in the past, the data protection scenario can be thought of as somewhat manageable, however given the more recent higher VM counts we have witnessed today, data protection of the environment is no trivial task. Balancing limits on VM growth due to data protection requirements and the expansion requirements requested from business units to cloud administrators is a daunting challenge. Oftentimes the environment continues to grow but portions are left unprotected or protected with less than ideal processes in place. The EMC Avamar deduplication backup software and system, with the use of VMware s vstorage APIs for Data Protection (VADP), addresses and removes these constraints for VMware environments. Avamar s data deduplication technology seamlessly integrates into virtual environments, providing rapid backup capabilities utilizing the Changed Block Tracking (CBT) feature within the API. Newly introduced in Avamar 6.0, the CBT process is now leveraged to speed the restore process as well. In some VMware cloud environments, administrators have made use of lower cost NAS or iscsi based storage as an option for storage of VMDKs. With this new release, Avamar can now extend its backup and restore feature set to those Data stores residing on NAS or iscsi platforms. Avamar s proven deduplication process along with these latest enhancements result in vastly less data traversing the virtual and physical network, and greatly reduces the amount of data being physically stored translating into realized capital savings and operational benefits for protecting virtualized environments and their data. Audience The white paper assumes the reader has a general understanding of the basic concepts and technologies behind EMC Avamar and VMware, and is intended for systems engineers, technical architects, implementation specialists, technical consultants, and individuals interested in leveraging the integration of currently shipping products and emerging technologies. 4

5 Introduction This whitepaper provides an overview of the features implemented in Avamar for fast, efficient, and secure backups of VMware virtual environments. This paper will particularly emphasize the newly introduced features for virtual environment data protection introduced in Avamar 6.0. There are essentially two methods of employing Avamar for virtual machine backup: Guest-level backup Image-level backup via VMware s vstorage APIs for Data Protection (VADP) While Guest-level backup may provide the necessary solutions for some virtual cloud environments, the Image-level backup feature leveraging the VADP feature set from VMware is where the maximum benefit can be achieved when leveraging Avamar. This is especially true in larger virtual cloud environments where scale and backup windows are the ultimate concern. Avamar allows for both guest-level and image-level backups to run simultaneously, allowing the administrator greater flexibility and efficiency of deployment in their particular environment s use case. For the scope of this paper we will concentrate mostly on the features implemented via VADP to enable Image-level VM backups and restores. The reader should familiarize himself with the following terms used throughout this document in the context of backup and recovery. A virtual machine (VM) houses the production data in its virtual environment. This solution was tested in an enterprise environment, so ESX Server was used as the VMware platform. Virtualization allows customers to reduce IT costs while improving efficiency, availability, flexibility, and manageability of their environment. Datastore is a VMware term for the storage that is added to house VMware File Systems (VMFS). The VMFS holds all of the files needed to leverage virtual machines. A VMDK file is a VMware image file that has the data that will be accessed by the application that runs in this VM. It is where the operating system and application are installed along with the data for the respective application. Changed Block Tracking (CBT) is a new VMkernel feature that keeps track of the storage blocks of virtual machines as they change over time. The VMkernel keeps track of block changes on virtual machines, which enhances the backup process for applications that have been developed to take advantage of VMware s new vstorage APIs. VMware vstorage APIs for Data Protection (VADP) enable backup software to perform centralized virtual machine backups without the disruption and overhead of running backup tasks from inside each virtual machine. 5

6 EMC Avamar is a deduplication backup and recovery software and system solution. It embodies client deduplication that eliminates data from backup streams before it crosses the network. Savings are realized on bandwidth, storage, and backup windows. EMC Avamar Data Store is a bundled EMC solution that combines Avamar software and EMC hardware in a preconfigured, turnkey solution for simplified ordering, installation, and service. The Avamar Data Store scales from a single node to a multi-node solution in order to meet the needs of remote offices to data centers. Avamar: Efficient Data Protection for VMware Environments. Guest-level Backup & Restore With the guest backup option client agents are deployed in the same manner as an Avamar solution is implemented for physical server backup. The Avamar client package is installed on each individual virtual machine and backups are sent to the Avamar server via the VMs virtual network interface. Just as with physical servers, specific configuration may need to be done via application specific plugins to support various application consistent backups supported via the agents installed on each client. As shown in Figure 1 below, the same efficiencies apply as is observed with physical server backup using Avamar, however naturally in this use case, the savings are in virtual resources allocated to the VM, not physical client hardware resources. Figure 1: Client Resource Usage for Traditional vs. Avamar Backups Some of the highlighted advantages to the Guest-level feature set: 6

7 Highest level of data deduplication Support for backup of applications inside the virtual machines Application consistent backups Support for partial or file-level restores Identical backup methods for physical and virtual machines No requirement for advanced scripting or VMware software knowledge Unchanged day-to-day procedures for backing up Image-level Backup & Restore With the image based backup option EMC Avamar integrates with VMware s vstorage API for Data Protection, a feature set within the vsphere server to offload the backup processing overhead from the client to a backup proxy server running as a VM. This proxy server can communicate with the vcenter server to mount a snapshot of a particular VM s vmdk to perform image level backup of that virtual machine. With this method deduplication is provided on the file level as well as on the.vmdk level. Performing an image-level backup of a VMDK, the ability to execute a bare metal restore replacing a VM instance or creating a separate instance is also possible and supported. VMs protected via Image-level in Avamar 6.0 can reside on NFS, iscsi, or SAN storage. Given the scalability and sheer explosion in the size of some VM environments the workload burden placed on one proxy server can quickly build up. In this scenario, the recommendation is to provision multiple proxies to handle the combined workload and increase the amount of parallelism occurring when performing VADP processes. With the provisioning of two proxy servers, we can now perform the VADP process on two VMs simultaneously for backup by Avamar. Previously, VMs were assigned manually by the administrator to specific proxy servers to assure proper load balancing. With the latest enhancements introduced within Avamar, this load balancing occurs natively. Avamar will now utilize any idle proxy server to automatically load balance workload and maximize parallelism through the backup process. While offloading the backup-processing overhead from the client under backup to a proxy server provides a lot of benefit, the usage of a proxy alone does not introduce efficiencies and intelligence needed to reduce the amount of data blocks which are scanned and processed by that proxy server. To introduce further efficiency into the VMware image backup process, Avamar fully utilizes the power of VADPs Changed Block Tracking (CBT) feature. As depicted in Figure 3 below, leveraging CBT allows the VM Image Proxy to query the vsphere environment and obtain an intelligent list of which blocks have changed on a specific VM since the last backup. Therefore, Avamar will only scan and process blocks which are included in the changed-block list provided by the CBT mechanism within vsphere. This greatly 7

8 reduces the backup time of a given VM image and is the cornerstone of Avamar s ability to process large numbers of VMs within a particular given backup window. Figure 2: Avamar VM Image Backup utilizing Changed-Block Tracking (CBT) Prior to Avamar 6.0, Restore operations were an all-or-nothing implementation as depicted in Figure 4. When restoring a particular VM image from a backup within Avamar, the entire VMDK would need to be sent over the network and restored.. Recovery of only the individual changed blocks since the last backup within that VM image was not possible. Figure 3: Avamar VM Image Restore classic scenario (not utilizing CBT) With the introduction of Avamar 6.0, CBT is now leveraged by Avamar software to introduce more efficient and lightning-fast restores. In this scenario, depicted in Figure 5, Avamar will query the VADP to determine which blocks have changed since the last backup, and then only recover or replace those blocks within the VM image file. This reduces data transfer traffic within the vsphere environment traversing the wire during a restore operation, and more importantly reducing the restore time objective (RTO) of a Virtual Machine Image. To further add to this intelligence, the Avamar software will automatically evaluate the workload between both restore methods (Full Image Restore, or a recovery leveraging CBT) and perform which method will result in the fastest restore times. This is particularly useful in the scenario where the change rate since the last backup on a VM being restored is very high and the overhead of a CBT analysis operation would be more costly than a direct full image recover. Avamar will intelligently decide which deployment method will result in the fastest VM Image recovery times for your particular scenario or enviornment. 8

9 Figure 4: Avamar VM Image Restore CBR scenario (utilizing CBT) Some of the highlighted advantages to this VMware Image backup feature set: Provides full image backups of running virtual machines Utilizes efficient transport (SCSI hotadd), which avoids copying the entire vmdk image over the network Provides file-level restores from image-level backups for Windows Deduplicates within and across all.vmdk files protected by Avamar Uses changed block tracking for faster backups & restores. Minimizes network traffic by deduplicating and compressing data Eliminates the need to manage backup agents in each virtual machine for most scenarios Leverages proxy server load balancing to achieve parallelism for superior backup throughput VM Data Protection Management: Avamar vcenter Integration Avamar 6.0 provides unique integration capabilities with VMware s vcenter management utility. The integration to the vcenter APIs allows the Avamar Management Console to routinely query a single instance or group of vcenter instances, and provide key data protection information that will simplify management of backup and recovery activities. One of the important features possible with this management integration with vcenter as shown in Figure 6 below, is the ability to quickly see from one userinterface the current protection status of each VM on a vcenter server, which is imported into the Avamar environment. This saves the backup administrator the trouble of having to correlate backup policies with newly created VMs that the application administrators are deploying. Most likely, this would be done by cross correlating the backup policy management UI with VMware s vcenter client UI. Now, the backup administrator, or even the application administrator (with the correct Avamar management permissions assigned) can be given access to the Avamar administrator UI and quickly assure that newly deployed VMs are indeed protected under policy and exactly which policy is protecting them. 9

10 For Recovery, Avamar s integration with vcenter provides the backup administrator with the flexibility for different VM recovery options. A VM backup can be restored to the same VM instance from which the backup was taken or, we can perform a redirected restore and create an entirely new VM instance within vcenter. All of the steps required to create the VM entry within vcenter have been done for you through this integration with Avamar. Once the recovery is complete, the only remaining step is to power on the VM that was created from the recovery process. As shown in Figure 7, Avamar even gives you the flexibility to deploy a re-directed restore of a VM to a different VM data store entirely. By implementing these features, the Avamar vcenter integration provides the administrator with the highest degree of flexibility to fit any recovery scenario. Key benefits and features of Avamar vcenter integration include: Discovery of VMs and their associated groups in the Avamar UI Ability to add individual VMs or groups and define image and/or guest backup policies Ability to define multiple VMware Image Proxies Ability to initiate VM image or guest backup/restore operations Ability to monitor backup/restore operations in the Activity Monitor Ability to view VM protection status (guest, image, or none) Simple views of whether VMs have been backed up or not; and the simple ability to remediate by quickly adding unprotected VMs to a backup policy group. Automatically adding a backup policy to virtual machines as they are added Figure 5: Determine a data protection approach by virtual machine 10

11 Figure 6: Ability to recover.vmdk files to different storage 11

12 Conclusion With the ever-increasing demands placed on virtual cloud infrastructures via new ITas-a-service deployments, the need to protect the environments with some sort of data protection scheme still remains. Employing traditional backup methods to the virtual environment may be sufficient at the onset, however as the environment quickly grows in size, backup windows begin to be largely unmanageable. Avamar has implemented the VMware features described in this paper and is already providing customers today with a more efficient VMware backup and recovery solution. Avamar 6.0 extends the improvement in backup process efficiency for VM backups, and continues to build upon its feature set with tighter integration and backup process options for the administrator. With features detailed in this whitepaper, EMC Avamar is continues to lead the industry making backup and restores for virtual environments more efficient and more importantly faster, allowing for worry-free and cost-effective expansion. References White Paper: Data Protection for Large VMware and Vblock Environments Using EMC Avamar Applied Technology VMware product pages on VMware.com Avamar Product Page on EMC.com Powerlink, EMC s customer- and employee-only extranet (registration required) 12