PERFORMANCE Analysis: Optimal Virtual & Physical Backup

Transcription

1 Data Center Management openbench Labs PERFORMANCE Analysis: Optimal Virtual & Physical Backup AppAssure v4.7 Backup and Replication Software vs. Acronis Backup & Recovery 11

2 PERFORMANCE Analysis: Optimal Virtual & Physical Backup AppAssure v4.7 Backup and Replication Software vs. Acronis Backup & Recovery 11 Author: Jack Fegreus, Ph.D. Managing Director openbench Labs October 12, 2011 Jack Fegreus is Managing Director of openbench Labs and consults through Ridgetop Research. He also contributes to InfoStor, Virtual Strategy Magazine, and Open Magazine, and serves as CTO of Strategic Communications. Previously he was Editor in Chief of Open Magazine, Data Storage, BackOffice CTO, Client/Server Today, and Digital Review. Jack also served as a consultant to Demax Software and was IT Director at Riley Stoker Corp. Jack holds a Ph.D. in Mathematics and worked on the application of computers to symbolic logic.

3 Table of Contents Table of Contents Executive Brief 04 Building Data Protection on Virtual Blocks 04 Test 1: Universal Backup Execution 08 Tracking Disk Blocks 08 Keeping Things Simple 09 Real Synthetic Differences 10 Test 2: Granular Application Recovery 12 The Road to Application-Centric SLAs 12 Finding Files 12 Automated Application Verification 13 Test 3: Standby VMs and Near-Zero DR 15 DR: The New Backup and Restore 15 Instant Volume Recovery 17 Test Summary 18 Rewriting the Rules of Business Continuity 18 03

4 Executive Brief Executive Brief F or Windows-centric sites, AppAssure Backup and Replication provides a powerful, cost-effective, unified, backup and Disaster Recovery solution that implements a changed-block methodology for both physical and virtual systems with unmatched RTO and RPO levels. BUILDING DATA PROTECTION ON VIRTUAL BLOCKS In this study of data protection for environments with virtual and physical servers running Windows, openbench Labs tested AppAssure Backup and Replication software v 4.7 and Acronis Backup & Recovery 11. Both solutions utilize block-based technology to unify data protection operations; however, the way each product implements a solution creates significant differences in performance and functionality. We designed our tests to stress IT management simplification and operating expense (OPEX) reduction via uniform access to all data protection options. We ran all tests within the context of a disk-to-disk (D2D) backup strategy using continuous incremental backups of virtual and physical servers, data deduplication, and full vaerification of each backup. In our tests, AppAssure ran 5X faster than Acronis on full and incremental backups with data deduplication and verification. Also, we found that Acronis backup files were typically 100X larger before data deduplication and Acronis agents imposed 4X more overhead on CPU during backups. OpenBench Labs conducted all tests using five physical systems, which included two Windows servers, two ESXi 5 servers, and a Windows workstation. All of these systems utilized a Fibre Channel storage area network (SAN) for storage resources. Within this environment, openbench Labs set up three different IT scenarios to host and evaluate our data protection tests. A D2D strategy provides IT with a number of operating efficiencies, to be economically viable versus a disk-to-tape (D2T) strategy; however, the storage utilization ratio between actual production data and a backup of that data must be on the order of 25 to 1. In addition to providing an excellent basis for storage space savings, the time needed to complete an incremental backup makes it possible to repeat backups frequently and thereby minimize the time differential between recovery points. Given the growth of application-specific SLAs for business continuity, recovery testing included an functional assesment of support for deep validation of application recoverability, operating tests concentrated on two scenarios for data-item level recovery: recovery of individual SQL Server databases and recovery of Exchange mailboxes and 04

5 Executive Brief messages. In addition we examined both products for specialized recovery features that support immediate recovery for a perceived near-zero recovery time. Under TesT: WindoWs server data-protection AppAssure Value Proposition 1) Live Recovery with Near-Zero Data Recovery Time: AppAssure intelligently reorders blocks during volume recovery to permit immediate access to critical application data during the recovery of a full volume 2) Assured Recovery for Automatic Application Validation: Extend backup validation processes by automatically discovering key applications, including SQL Server and Exchange, on clients and then testing application recoverability in each backup 3) Cross-platform Universal Recovery to any VM or physical server: Any backup can be restored to a hot-metal backup CD for any hardware or used to build a VM on any Virtual Infrastructure host 4) Universal Recovery for Disaster Recovery (DR): Automatically update system and data files on a warm standby VM and user data on a hot standby physical server after every backup 5) Granular Universal Recovery of Files and Application Items: Retrieve files or individual data objects, such as an messages and database objects by mounting and sharing any backup as a virtual disk 6) Changed Block Tracking on All Backups: AppAssure Backup and Replication client installs a filter driver that tracks all data changes by disk blocks on virtual and physical systems running Windows 7) Minimal Data Loss with Near-Continuous Recovery Points: AppAssure leverages block-level data change tracking to provide fast, small footprint, incremental backups with automatic roll up to synthetic full backups, which can be scheduled in five minute intervals 8) Off-site DR via WAN and LAN Backup Replication: Automatically replicate backup archives for enhanced off-site availability of warm, standby, virtual servers and hot, standby, physical servers In our third test suite, we examined the ability of AppAssure and Acronis Backup & Recovery 11 to extend data protection to disaster recovery functionality. Beyond generation of a bare metal installation CD, which leaves IT with several hours of work to configure a new system, we examined the ability to leverage a warm standby VM. By aggressively exploiting its changed block tracking mechanism across all data protection operations, AppAssure was able to forge a measurable advantage in all three of our test suites. More importantly, AppAssure leveraged block-based tracking in the introduction of three key technologies: Live Recovery to meet nearzero RTO and five-minute RPO; Assured Recovery to automatically verify that both a backup is recoverable and that application data within the backup is recoverable; and Universal Recovery to support granular recovery of files and application items, as well as bare metal recovery that can be physical-to-physical (P2P), virtual-to-virtual (V2V), physical-to-virtual (P2V), or virtual-to-physical (V2P). In our tests, AppAssure s changed block tracking proved to be the key distinguishing technology when comparing data protection performance and functionality with Acronis Backup & Recovery 11. Since Acronis Backup & Recovery 11 transfers entire files during full, differential and incremental backups, it creates much larger backup files than those of AppAssure, which makes data deduplication a top priority. While deduplication time differentials between Acronis and AppAssure were most dramatic on initial full backups, the time needed for incremental backups has the most 05

6 Executive Brief impact on the ability of IT to meet stringent Restore Point Objectives (RPOs). By maintaining minimal time intervals between incremental backups, IT can use near continuous incremental backups to minimize potential data loss. Nonetheless, to enable frequent incremental backups, CPU overhead must also be kept to a minimum. Data Protection Test Suite Universal Backup Execution Granular Application Recovery Standby VMs and Near-zero Disaster Recovery openbench LABS DATA PRoTECTIoN TESTING SUMMARy Key Test Metrics Analysis AppAssure v4.7 Unified execution of all commands Backup time Client CPU overhead Backup file size Extended validation of data objects Restoration of itemlevel data from any backup Utilize VM clones of physical and virtual systems for DR Restore applications and data with no perceived delay Execution of all options from a single GUI lowers operation complexity Backup time governs RPO Service overhead restricts backup window options Backup size directly affects resource costs Application validation essential for SLA support ot both RTO and RPO Tested the ability to restore objects from a SQL Server database and messages from an Exchange 2010 mailbox Update standby VMs OS and data with production server disk snapshots from backups Restore applications and data with no perceived delay All options run from a single management GUI Fastest backup times Minimal CPU overhead Smallest incremental backup files Protected applications automatically discovered and validation tests added Status of databases and mailboxes shown in GUI and any backup can be used to recover data objects Standby VMs configured identically to production servers Supported an Exchange mailbox restore while passing a Jetstress benchmark Acronis Backup & Recovery 11 Data item backup requires additional modules and agents Data deduplication significantly extended backup time Moderate CPU overhead Data deduplication needed for small backup files Separate application modules and clients that create application-specific backups SQL Server 2008 R2 databases could be backed up and restore, but not Exchange 2010 mailboxes Minimally configured standby VMs Active With AppAssure, CPU usage by the client service peaked at 8% in an initial backup that lasted 24 minutes. On the same server, Acronis Backup & Recovery 11 peaked at 58% CPU utilization and averaged over 30% for 80 minutes. What s more, this overhead was measured with data deduplication run on the backup server. Acronis offers the option to run data deduplication on the client system to lower network overhead; however, with gigabit networking, openbench Labs did not invoke that option given the 06

7 Executive Brief added processing overhead and inherent insecurity of leaving single instance data on the client. Equally important for today s CIO is the openbench LABS DATA PRoTECTIoN TEST SCENARIoS ability to support an application-specific 1) Corporate Scenario: SLA for business one virtual server running Windows Server 2008 R2 as a Domain Controller continuity. This one virtual server running Exchange Server 2010 means IT operations one physical workstation running Windows 7 and outlook 2007 managers must know 2) Database-driven Business Process Scenario: that applications one physical server running Windows Server 2003 R2 as a Domain Controller within a backup will one virtual server running Windows Server 2008 R2 and SQL Server 2008 R2 be recovered in one physical server running Windows Server 2008 R2 and SQL Server 2008 R2 working order when a backup is restored. 3) End-User Desktop Workstation Scenario: To meet that one physical workstation running Windows 7 requirement, one virtual workstation running Windows 7 AppAssure provides Assured Recovery to automatically test that applications can be recovered as part of the normal restore process. In contrast to the automation of AppAssure, Acronis requires IT administrators to manually install optional modules for SQL Server and Exchange, which create separate client services to handle their respective applications. These modules also require IT to create separate application-specific backups. With Acronis Backup & Recovery 11, an IT administrator cannot simply recover a database from a standard backup of a system containing SQL Server. As a result, AppAssure uniquely empowers a CIO to confidently agree to and deliver on very aggressive RTO and RPO propositions. What s more, AppAssure dramatically reduces both the capital and operating costs associated with data protection and DR while simultaneously addressing the issues of fine-grained data item recovery, system replication, and bare-metal system restoration. 07

8 Universal Backup Execution A ppassure is able to meet a 5-minute RPO by Test Suite1: Universal Backup Execution aggressively leveraging its disk block tracking scheme to only processes data blocks altered when changes are made to a file: There are no unchanged segments of data that need to be deduplicated. TRACKING DISK BLOCKS To protect data, traditional backup solutions transfer server files to an alternate storage medium. Unfortunately, file-level backups do not extend easily to other data objects. When IT needs to recover data items contained in files or virtual systems hosting files, traditional backup packages often require optional modules, which increase capital and operating costs by introducing new logical processing models. In sharp contrast, AppAssure introduces a deceptively simple mechanism to track and flag data changes to disk blocks rather than files. By using changes to disk blocks instead of files, AppAssure supports a unified, disk-imaging approach for all data protection and DR functionality. APPASSURE I/O REDIRECTION On a workstation, we observed AppAssure client service activity, while generateing a high level of I/O writes. As the benchmark changed file data, AppAssure s client service logged meta data about the block changes to an AppAssure (AA) log file in the disk s System Volume Information directory. At the same time, the client service was also updating the AppAssure service on the Core server. To establish a generalized disk-block tracking mechanism on Windows-based systems, an IT administrator installs an AppAssure service agent on every client system to collect, package, and send block data to a central AppAssure Core server. The AppAssure agent installs a filter driver between the Windows file system and the Windows kernel, to capture blocklevel changes on the underlying logical disk volume associated with data changes in files made by applications. Using the filter driver, AppAssure service agents on client systems log meta data about 08

9 Universal Backup Execution disk-block changes in the System Volume directory for each logical disk. During a backup, the agent utilizes meta-data logs to send just the block-level data changes that occurred since the last time an AppAssure Core server requested a backup data transfer. More importantly, since AppAssure data protection is based on using disk images, IT administrators are able to immediately mount and share any AppAssure backup as a virtual volume. In this and other recovery processes, AppAssure automatically rolls up a synthetic backup for the selected recovery point. In addition, administrators are able to set up replication between two AppAssure Core servers across a LAN or WAN to improve data availability and DR performance with respect to RTO. KEEPING THINGS SIMPLE Of particular concern for openbench Labs is the ability of software packages to simplify IT operations. For data protection software, a critical factor is the ability to minimize operating complexity by allowing IT administrators to implement all backup and recovery options using a minimal set of GUI commands. A central issue in comparing the ease of use and performance of AppAssure with that of Acronis Backup & Recovery 11 is the intended scope of the two products. AppAssure is designed explicitly for use in an environment that enables implementation of its blocklevel tracking. Acronis Backup & Replication 11, on the other hand, is designed to support the largest possible range of servers in the largest possible number of environments. To meet this goal, Acronis supports two paradigms: individual servers with self-managed backup and centrally managed backup for all servers. ACRONIS DATA DEDUPLICATION We set up a special storage vault for backup files that were created using a backup plan invoking data deduplication. This vault worked with both full and incremental backups. After running a small number of backups, the overall data reduction rate reached 20 to 1, a level considered critical for D2D backup to be cost competitive with tape. With our cross-platform mix of physical and virtual servers, we attempted to restrict our evaluation to the Acronis centralized management scheme, which propagates management operations to clients. On our management server, we created centralized backup plans for 09

10 Universal Backup Execution all clients and two centralized archive storage vaults for use with plans that either did or did not apply data deduplication. We stored all backups with data deduplication on our centrally managed archive to restrict data deduplication processing to our central server and avoid adding excessive CPU overhead to production systems. The need for a separate storage vault for data deduplication points to an important architectural difference between AppAssure and Acronis. To maintain compatibility with the broadest number of client systems, Acronis Backup & Recovery 11 performs a number of advanced features, including data deduplication, in the same way that traditional file-oriented data protection packages do. This means that Acronis Backup & Recovery 11 transfers entire files during full, differential and incremental backups, which creates much larger backup files than those of AppAssure. Before applying data deduplication, a typical Acronis incremental backup file averaged 5GB, while an AppAssure incremental backup file averaged 5MB. The larger backup files created by Acronis are of no consequence for a D2T backup plan; however, a cost-effective D2D backup strategy will require data deduplication. To deduplicate data, Acronis Backup & Recovery 11, breaks a stream of backup data into segments and attempts to match each segment with a hash-coded fingerprint that identifies a previously stored copy of the segment. If a match does occur, Acronis simply replaces the known segment in the backup file with a copy of the fingerprint pointer to the stored segment. If no match occurs, Acronis stores the segment as a new singleinstance segment and creates an associated fingerprint. REAL SYNTHETIC DIFFERENCES Storage Reduction: Full Backup & Verification Data Deduplication and Compression Target (Backup Type) Physical Server (Initial Full) Windows 2008 Server R2, SQL Server 2008 R2, 49.1GB active data Physical Server (Incremental) Windows 2003 Server, Domain Controller, 21.8GB active data Virtual Server (Initial Full) Windows 2008 Server R2, SQL Server 2008 R2, 29.5GB active data Virtual Server (Incremental) Windows 2008 Server R2, SQL Server 2008 R2, 29.5GB active data Backup Software Backup File Backup Window AppAssure 23.1GB 38 minutes Acronis 19.5GB 166 minutes AppAssure 32MB 2 minutes Acronis 95MB 13 minutes AppAssure 10.3GB 27 minutes Acronis 8.8GB 73 minutes AppAssure 3MB 1 minute Acronis 18.6MB 7 minutes As with AppAssure, we were able to use the Acronis data deduplication scheme with any backup, including full and incremental backups. What s more, we encountered no problems rolling up incremental backups with deduplication into synthetic backups. What we could not do with Acronis Backup & Recovery 11 was intermix backups with and without data deduplication. The size of full and incremental backup files were relatively close between two data protection packages. As a result, an 10

11 Universal Backup Execution DATA DEDUPLICATION DOWNSIDE AppAssure archive and an Acronis archive for a continuous incremental backup strategy should exhibit similar capacity utilization patterns over time. In contrast to storage capacity requirements, Acronis typically took 4 to 5 times longer than AppAssure when running either an initial full backup or an incremental backup using data deduplication. While deduplication time differentials between Acronis and AppAssure were most dramatic on initial full backups, the time needed for incremental backups has the most impact on the ability of IT to meet stringent Restore Point Objectives (RPOs). By maintaining minimal time intervals between incremental backups, IT can use near continuous incremental backups to minimize potential data loss. We tracked CPU usage by the AppAssure and Acronis services during initial and incremental backups. Even with data deduplication processing running exclusively on the central backup server, overhead on the production server being backed up was significantly higher. With AppAssure, CPU usage by the client service peaked at 8% in an initial backup that lasted 24 minutes. On the same server, Acronis Backup & Recovery 11 peaked at 58% CPU utilization and averaged over 30% for 80 minutes. AppAssure is able to meet a 5-minute RPO by aggressively leveraging its disk block tracking scheme to only processes data blocks altered when changes are made to a file: There are no unchanged segments of data that need to be deduplicated. The only potential source of duplicate data is the changed block backup data itself: There may be multiple instances of a change within a document or multiple documents with the same change. To deal with data duplication within changed blocks, AppAssure restricts deduplication to just the current backup and avoids the level of extended wall clock time and CPU processing overhead that characterizes Acronis global deduplication scheme. 11

12 Granular Application Recovery F or an SMB site with overly stretched IT Test Suite 2: Granular Application Recovery resources, the value of AppAssure s Assured Recovery for automatic discovery of critical applications and automatic configuration of data validation tests for the restoration of data items cannot be over estimated. THE ROAD TO APPLICATION-CENTRIC SLAS For IT, backup has long been a necessary daily activity centered on backing up data, applications, and OS files in a minimal amount of time. From the perspective of a Line of Business (LoB) executive, however, the value of any data-protection operation rests solely in recovery processes. That s why Service Level Agreements (SLAs) for data protection focus on applications and target an RPO and RTO: Backup is simply a means to provide a recovery point. With the growth of application-specific SLAs for business continuity, we focused recovery testing suite on an assesment of each package s ability to go beyond verification of backup recoverability and validate the recoverability of applications within a backup. We followed this assessment with operating tests centered on two business scenarios. Specifically, we attempted to restore individual SQL Server databases and messages in an Exchange mailbox. The lion s share of restore operations for IT, however, remain dominated by the simple retrieval of individual files inadvertently lost or corrupted in daily use by end users. For this reason, we began our testing with the issue of recovering a single file for use on our physical domain controller running Windows Server 2003 R2. FINDING FILES With AppAssure s aggressive leveraging of disk blocks and imaging technology, an IT administrator can instantly mount any backup file as a logical volume on an AppAssure Core server. Then using standard Windows file sharing, the AppAssure Core server can distribute the mounted volume over a LAN. With the capability to mount and share any backup file incremental backups are automatically rolled up as a logical disk volume, IT can easily turn the task of file-and item-level data recovery into a simple, self-serve, end-user process. More importantly, the ability to mount and share a backup file also opens the door to providing end users with the ability to use existing application tools to manipulate any application-level data items. File restoration with Acronis Backup & Recovery 11, however, was burdened by multiple incompatible features and functions. Like AppAssure, Acronis allows a backup file to be mounted on a client system. Nonetheless, this process can not be run from a centrally managed backup vault. To mount a backup as a disk on a client system, the backup file needed to be stored in a local unmanaged vault on the remote client. The critical issue in this scenario is the need to keep a separate backup on the client system. 12

13 Granular Application Recovery The alternative to the scenario of mounting a backup file as a volume requires IT administrators to follow a classic file-oriented recovery process. An IT administrator drills down on a managed archive and searches for files rather than volumes. When the appropriate file is discovered, the administrator will have a choice of backup restore points based on backup dates. Nonetheless, this process can be deceptive: Any backup date corresponding to an incremental backup will not be automatically rolled up and can result in the restoration of a pointer rather than the desired file. AUTOMATED APPLICATION VERIFICATION For IT, the ability to support an application-specific SLA for business continuity begins with knowing that applications within a backup will be recovered in working order whenever the backup is restored. To meet that requirement, AppAssure has introduced Assured Recovery, which automatically validates the application as part of a normal backup process. APPASSURE APPLICATION VALIDATION When a client system is added to an AppAssure Core server, the client is scanned to discover if any protected applications are installed. If AppAssure discovers a protected application, such as Exchange, SQL Server, and Sharepoint, it will add applicationspecific validations for that client and schedule those validation tests along with AppAssure s standard backup validation. The new validation tests include checks for database integrity and database attachability. In contrast to the automation of AppAssure, Acronis requires IT administrators to manually install optional modules for SQL Server and Exchange, which create separate client services to handle their respective applications. What s more, these modules also require IT to create an application-specific backup. IT When a client system was added to an AppAssure Core administrators cannot simply recover a database from a server for backup, it was automatically scanned for the backup of a system containing SQL Server. Using presence of protected applications and application-specific Acronis, we needed to generate a database-aware validation tests were added to its properties. backup of all database instances running on a server, before we were able to restore any of those database instances on any server running SQL Server. Nonetheless, we were not able to create a special backup of an Exchange 2010 mailbox database. While we were able to backup and restore systems running Exchange 2010, the special module to backup mailbox databases could not parse an Exchange 2010 mailbox. On the other hand, we easily ran all restoration options for Exchange and SQL Server from the main AppAssure GUI. The GUI presented the application s validation state and all recoverable items, such as an SQL Server databases and Exchange mailboxes. For our 13

14 Granular Application Recovery Exchange 2010 server, we were able to drill down on an Exchange mailbox using an ersatz Outlook GUI and select items for recovery directly from any backup. UNIVERSAL ITEM-LEVEL RECOVERY We mounted and shared an AppAssure backup of a server running SQL Server 2008 R2 as a logical disk. Using the SQL Server Management Studio, we were able to import the volume and attach any database contained in the backup. Once backup was attached to our local database, we could browse and save data items, including tables and views. To recover a SQL Server 2008 R2 database with AppAssure, we started with an existing server backup that included validated database instances. We then mounted and shared that backup as a disk volume from the AppAssure Core server. On any server running SQL Server 2008 R2, we were able to mount that volume and attach any of the databases contained in the backup in order to retrieve fine grain items such as views and queries using standard SQL Server tools. The key added value from AppAssure were the tests that we would be able to attach all of the databases contained in the restore point. For an SMB site with overly stretched IT resources, the value of AppAssure s Assured Recovery for automatic discovery of critical applications and automatic configuration of data validation tests for the restoration of data items cannot be over estimated. 14

15 Standby VMs and Near-zero DR W hen a protected AppAssure client Test Suite 3: Standby VMs and Near-zero DR crashes, a warm standby VM server can be booted in seconds, come online to process data in minutes, and satisfy the most stringent business continuity SLA with respect to an aggressive RTO. DR: THE NEW BACKUP AND RESTORE DR VM STANDBY & REPLICATION TOPOLOGY AppAssure is able to automatically turn any incremental backup into a bare-metal recovery CD or update the user files on a running standby physical server. Similar DR functionality can found within Acronis Backup & Recovery 11, however, AppAssure also features a far more powerful third option derived through AppAssure s use of block-based disk imaging. For our Exchange 2010 server, we set up data protection to include a warm standby VM. on an ESXi host. Following each incremental backup of the Exchange server, AppAssure sent an update snapshot for each of the standby VMs disk to the ESXi host. Next, we added replication of the backup files to a second AppAssure Core server and made that server the new source of disk snapshots for the VM. ESXi and ESX hosts can update VMs that are not in a running state. That allows an AppAssure Core server to use incremental backups of any physical or virtual system to generate disk snapshots for a warm standby VM, which can be a perfect copy of the original system down to the state of the OS. While Acronis Backup & Recovery 11 can create a warm backup VM of a physical server, that backup is not provisioned with identical resources, such as memory, and the update process requires the presence of an Acronis appliance on the host server. On the other hand, the AppAssure standby VM is configured to boot directly from a standard host datastore and will immediately exhibit full I/O performance. What s more, the 15

16 Standby VMs and Near-zero DR standby VM server will take the complete identity of the original system on the site s LAN. As a result, when a protected AppAssure client crashes, a warm standby VM server can be booted in seconds; come online to process data in minutes; and satisfy the most stringent business continuity SLA with respect to an aggressive RTO. LOW IMPACT APPASSURE BACKUP WITH HOT DR STANDBY Using AppAssure with incremental updates in 10-minute intervals, we easily met aggressive RTO and RPO levels while placing minimal overhead on IT infrastructure. Every 10 minutes, we ran an incremental backup process, which included data compression and deduplication. The backup took about 4 minutes to complete 3 minutes to back up and 1 minute to verify the data. Backup files for this process were typically well under 50MB. What s more, we were also able to automatically update a warm standby VM within that 10 minute window by applying snapshot updates. In about 7 minutes, we processed an incremental backup of our Exchange 2010 R2 server and updated a standby VM server for DR. 16

17 Standby VMs and Near-zero DR An important key to AppAssure s ability to keep a warm standby VM updated via disk snapshots is the minimal overhead required by an AppAssure Core server to process incremental updates and transfer corresponding disk snapshots to a VM. The entire process of capturing an incremental backup on the client, sending, processing, and saving the update on the AppAssure Core server can be repeated over very short intervals that are measured in minutes. As a result, the RPO for a business continuity SLA can be just as aggressive as the RTO. What s more, AppAssure backups are self contained, which allows backups on one Core server to be replicated to another Core server for an HA scenario. Replicating the small, compressed and, deduplicated incremental backups puts minimal stress on a LAN infrastructure and is very well suited to WAN infrastructure as well. As a result, IT can garner even greater efficiency by utilizing a WAN to keep an off-site secondary AppAssure Core server updated. That server can then securely update a VI host maintaining a warm standby VM at the off-site location using disk snapshots created from the incremental backups generated for a server at the home site. INSTANT VOLUME RECOVERY AppAssure Live Recovery is a unique volume restoration feature that leverages block data to provide end users with zero perceived restore time, which is manifested in immediate access to any data on the volume as it is being restored. With Live Recovery, the restoration legerdemain for a logical volume starts with the transfer of the volume s Master File Table (MFT). With the MFT in place, users immediately see all of the files that were on the drive at the time of the restore point. As a result, end users have the impression that the drive has been fully magically restored in seconds. The AppAssure instant recovery scheme is not without very serious potential pitfalls. The most obvious question is: What happens when an end user clicks on a file that is not there? Without a working solution to that problem, the consequences of such an action for a simple single-user application will probably be no more than a very annoyed end user spending an extended period of time watching a rotating mouse icon. In a databasedriven environment, however, there is the distinct risk of corrupting one or more critical internal tables or worse, causing considerable delays and problems for mission-critical, transaction-processing applications that are utilizing a database. To avoid these issues, AppAssure s Live Recovery relies on critical coordination between the AppAssure client service and the and the AppAssure service on the Core Server handling the Live Recovery process. When an application attempts to access any file or data item that is still queued on the AppAssure Core server, the requested data block addresses are transferred to the Core server which reorders the block stream queued for the client in order to put the requested addresses at the top of the queue. As a result, a large volume file server or Exchange mailbox database with hundreds of gigabytes of data can be restored instantaneously from the perspective of end users. 17

18 Test Summary Test Summary I T can leverage the incremental backup processing advantages of AppAssure to run frequent incremental backups in order to minimally space recovery points for mission critical systems and then use standby VM servers to double down on an aggressive DR plan with an RTO measured in minutes. REWRITING THE RULES OF BUSINESS CONTINUITY Concerns expressed by Line of Business (LoB) executives over business continuity are in part driving the next wave of IT projects. In a competitive 24x7 economic environment, computer downtime represents more than lost revenue to sales and marketing executives. These executives equate lengthy computer outages with potential losses in customer confidence and market share. As a result, senior LoB executives expect IT to meet an RTO that is measured in hours rather than days and an RPO that is close to lossless. APPASSURE FEATURE BENEFITS 1) Agent-based Changed Block Tracking: IT administrators install agents on client systems that utilize a filter driver to track block-level changes to greatly reduce the processing of incremental backups 2) Compress and Deduplicate Data on any Backup Process: AppAssure can apply both compression and data deduplication to incremental backups 3) Universal Recovery to Any Hardware: Recover systems using a bare metal recovery CD, a hot standby server or a warm standby VM 4) Universal Recovery at Any Granularity: Recover systems, disk volumes, files, or application-level data items, such as messages and database tables 5) Automatically Test and Verify Backups for Application Recoverability: AppAssure discovers key applications, such as SQL Server and Exchange, on clients and applies special item-level verification tests for these applications 6) Live Recovery Restores Volumes and Key Application Files with Zero Perceived Delay: Live Recovery immediately restores directory details and reorders the transfer of blocks based on user access of files during recovery 7) Automate Incremental Backups For Near-Lossless RPO: Incremental backups with both deduplication and compression can be automated to run in intervals as short as every 5 minutes for minimally spaced restore points 8) Restore or Repair Application Items: Mount and share backup files as virtual disks from AppAssure Core servers lab to enable the recovery of applicationrelated objects using existing application tools With respect to meeting stringent RPO and RTO goals, AppAssure Backup and Replication software is designed to leverage changed disk blocks in place of changed files on any Windows system whether physical or virtual. By installing a client service that includes a filter driver that updates logs in the system volume directory of each disk, AppAssure is able to leverage disk image technology to generate fast, low-impact, incremental backups. The incremental backups are maintained as restore points on an AppAssure Core server and automatically rolled up to a full synthetic backup when accessed for a recovery process. More importantly, the block-based architecture of AppAssure enables the universal application of all functions and features with all 18

19 Test Summary backups. In contrast, Acronis Backup and Recovery 11 has a list of features and functions that are not compatible. For an SMB site, feature and function incompatibility can excessively burden IT administrators with overly complex data protection procedures. Far more important, however, is the minimal amount of computer processing needed to support and optimize incremental backups made using changed disk blocks. In particular, the minimum amount of overhead generated by AppAssure empowers IT to implement a DR plan with aggressive RTO and RPO levels to support an SLA with Line of Business executives. In particular, IT can leverage the incremental backup processing advantages of AppAssure to run frequent incremental backups in order to minimally space recovery points for mission critical systems and then use a standby VM server to double down on an aggressive DR plan with an RTO measured in minutes. 19