WHITE PAPER: ENTERPRISE SECURITY Symantec Backup Exec Quick Recovery and Off-Host Backup Solutions for Microsoft Exchange Server 2003 and Microsoft SQL Server
White Paper: Enterprise Security Symantec Backup Exec Quick Recovery and Off-Host Backup Solutions Contents Introduction........................................................................4 Solution Components................................................................5 Symantec Backup Exec Advanced Disk-based Backup Option.............................5 Veritas Storage Foundation for Windows.................................................5 Veritas FlashSnap Option.............................................................5 Customer Advantages...............................................................6 Volume Shadow Copy Service.........................................................7 Quick Recovery.....................................................................8 Off-Host Backup....................................................................9 Deployment Information............................................................11 Software Components..............................................................12 Deployment Best Practices..........................................................13 For More Information...............................................................15
Introduction Microsoft Exchange Server and SQL Server are mission-critical components in today s business environment. IT administrators need to ensure that access to data and email communications for employees, customers, and partners is maintained 24 hours a day, 7 days a week. The greater reliance on all forms of electronic communication raises the potential of quickly escalating into a business disaster when any event causes mission-critical email and database data to become unavailable. The Symantec Backup Exec Advanced Disk-based Backup Option (ADBO) with Veritas Storage Foundation for Windows and the Veritas Storage Foundation for Windows (SFW) FlashSnap Option are combined to create the industry s first comprehensive solution for customers that want quick recovery and off-host backup support for Microsoft Exchange Server 2003 and Microsoft SQL Server. This solution eliminates backup windows, reduces the performance load on application servers, and quickly brings applications back online after data corruption issues. This solution leverages the Volume Shadow Copy Service (VSS) capabilities built into Microsoft Exchange Server 2003, Microsoft SQL Server, and Microsoft Windows Server 2003. The solution is hardware-independent and supports most leading Fibre Channel and iscsi SAN arrays. Additional, hardware-based VSS snapshot providers are supported with this solution but are outside the scope of this paper. Please see the Backup Exec Hardware Compatibility List for a complete listing of hardware-based VSS providers certified with Backup Exec 11d (http://support.veritas.com/menu_ddproduct_bewnt_view_cl.htm). 4
Solution components The Symantec Quick Recovery & Off-Host Backup Solution includes the Symantec Backup Exec Advanced Disk-Based Backup Option, Veritas Storage Foundation for Windows, and the Veritas FlashSnap Option. Customer prerequisites include: Microsoft Windows Server 2003 SP1, Microsoft Exchange Server 2003 SP1 or Microsoft SQL Server 2000 SP4, SQL Server 2005 SP1, a SAN or shared SCSI environment, Symantec Backup Exec Media Server, and the appropriate Backup Exec Agents for Exchange Server or SQL Server, which include a remote agent for Windows servers. Symantec Backup Exec Advanced Disk-based Backup Option Off-host backups virtually eliminate backup windows and network bandwidth requirements, and do not impact the production server. Additionally, off-host backups allow for quick client restore from a single backup image to reduce the number of tapes and eliminate the need to restore from incremental backups. The off-host backup feature enables better backup performance and eliminates backup processing overhead on the protected application server by processing the backup operation on a Backup Exec media server instead of on the application server. Veritas Storage Foundation for Windows By reducing both planned and unplanned downtime, Veritas Storage Foundation for Windows significantly increases the amount of time data is accessible to users. Traditional disk storage management is a labor-intensive process, often requiring systems to be taken offline for hours at a time, disabling users access to data and requiring tedious, manual intervention by system administrators. Storage Foundation overcomes the obstacles of traditional disk management by providing easy-to-use online disk storage management for mission-critical, enterprise Windows environments. Storage Foundation enables high availability of data and optimized storage I/O performance, and protects current storage investments while also allowing freedom of choice for future storage hardware investments. Veritas FlashSnap Option Veritas FlashSnap makes it possible to create independently addressable, point-in-time snapshots that are copies or mirrors of the volumes on a server. These snapshots can be easily moved to another server for backup or other purposes such as testing or data mining. These activities can be performed without affecting the normal functions of mission-critical servers. 5
The snapshots may also be kept on the same server for quick recovery from data corruption issues. Using roll-forward recovery, users may choose to recover to the point in time of the last snapshot or to the point of failure. Even when a FlashSnap operation is performed on the same server, its efficient mirror break-off and join processes are much faster and take fewer CPU cycles than other mirror break-off procedures that use ordinary mirroring. FlashSnap supports Windows Server 2003 Volume Shadow Copy Service (VSS) as a VSS Provider for Microsoft Exchange Server 2003 and Microsoft SQL Server 2000 and 2005 environments. By leveraging VSS, which is Microsoft s approved and supported technology for taking snapshots, Veritas Storage Foundation for Windows FlashSnap Option can create exact point-in-time copies of data to be used instantly for quick recovery, off-host backup and other processing. Customer advantages Easy to buy One part number includes all the software required Leverages Microsoft Volume Shadow Copy Service (VSS) architecture Microsoft Windows Server 2003 Microsoft Exchange Server 2003 Microsoft SQL Server 2000 and 2005 Heterogeneous array support works with most leading storage arrays Supports most leading Fibre Channel SAN arrays Supports most leading iscsi SAN arrays Quick recovery Point-in-time snapshots Point-of-failure or roll-forward recovery Quick recovery in minutes versus hours Off-host backup Minimal or no backup window No performance load on application server Backup server can back up at Fibre Channel speeds No LAN performance impact 6
Volume Shadow Copy Service With the release of Windows Server 2003, Microsoft introduced a new storage management technology called Volume Shadow Copy Service (VSS). VSS offers a framework for applications and storage to perform coordinated data snapshots. Because the business application (VSS writer), storage (VSS provider), and backup application (VSS requester) are tightly coordinated, Microsoft is able to coordinate the snapshot quiesce point while guaranteeing data integrity. The Microsoft VSS Shadow Copy technology is the basis of the backup/restore infrastructure in Windows Server 2003. VSS-enabled backup applications can utilize VSS to achieve consistent online backups of data and files that are open during the backup. This is accomplished by VSS facilitating communication between the following VSS components: VSS requestors Backup or management applications that invoke VSS to initiate basic functions such as creating, importing, or deleting snapshots. Examples: Backup Exec, Veritas NetBackup, FlashSnap. VSS writers Application-specific software modules that ensure the consistency and integrity of an application s data when a snapshot is taken. With VSS, the responsibility for data consistency shifts from the requestor application to the production application. The advantage is that application developers, who are most knowledgeable about their application, can ensure maximum effectiveness of the snapshot process through development of their own writers. Examples: Exchange Server 2003 Writer, SQL Server 2005 Writer. VSS providers Expose the mechanism for hardware- or software-based snapshots. Hardware vendors are responsible for writing providers for their storage arrays. Software vendors, such as Symantec, also write snapshot providers. Windows Server 2003 includes a system software provider with snapshot (shadow copy) functionality, and supports multiple hardware and software providers [On its own, VSS follows a default hierarchy when selecting a provider during the snapshot creation: hardware provider first, followed by software provider, then the system software provider (Copy-on-Write [COW] provider). The requestor can, however, override this hierarchy and specify the provider to use. 7
Writer (SQL) 2. Writer provides XML description of backup components and defines restore method Requestor Writer (Exchange) Writer (other app/store) 5. VSS freezes writers Volume Shadow Copy Service 1. Requestor asks VSS to enumerate writers and gather their metadata 4. Requestor asks VSS to create shadow copies Writer (other app/store) Writer ( ) 7. VSS thaws writers 3. VSS asks which providers can support a shadow copy for each of the required volumes 6. VSS tells providers to create the shadow copy of the current state on-disk Provider (Windows copy-on-write) Provider (EMC/Clarilion hardware) Provider (Veritas Storage Foundation for Windows FlashSnap) Disk 1 Disk 2 Disk 3 Disk 4 Disk 5 Disk 6 Figure 1. The Volume Shadow Copy Service process Quick recovery Usually backups or incremental backups are conducted nightly. In the example below, if a business is running all day and there is a failure at 13:00, it s necessary to go back and recover from media this can be a very lengthy and tedious process that causes an organization substantial downtime by the time it finally recovers. Restoring from backup takes hours at best and only provides the ability to restore to the point in time of the last backup. Transactions that occur after that point are lost. 8
2:00 10:00 12:00 14:00 16:00 18:00 Transactions Full Backup 13:00 Tape Restore In production Transactions Full Backup 13:00 In production much faster Snapshot on disk 2:00 10:00 12:00 14:00 16:00 18:00 Figure 2. Standard recovery vs. quick recovery Symantec provides administrators with the ability to recover in minutes. In this example, the administrator has taken a snapshot. Once created, the snapshot remains on the Exchange server where it s available to enable quick restoration; as stated earlier no data transfer from disk or tape is required. The Exchange or SQL databases can be mounted immediately using the snapshot volume. In the example above, if there is a failure at 13:00, all that is needed is to recover from the snapshot to achieve a point-in-time recovery. If a point-of-failure recovery is preferred, the transaction logs must be replayed before it s possible to return to production. This is an ideal way to painlessly recover from logical errors and increases a business ability to be resilient to unplanned downtime. The business can be up and running dramatically faster than with the standard data recovery techniques. Off-host backup Today s IT administrators are faced with the daunting task of ensuring business continuity by protecting their company s data. Backup operations are becoming increasingly complex due to mixed environments, as well as the need for increased application availability that requires those applications to be backed up even while in use. Three key challenges facing IT administrators during backup operations are: 9
Incomplete backups. One measurement of a quality backup is that all files are backed up completely, enabling a point-in-time recovery. In the event that a recovery is needed, the ability to recover all files at the point in time ensures data consistency. Minimal or no backup window. Today s fast-paced, competitive business environment requires networks to be operational around the clock. Web sites, email systems, and other databases must be available 24 hours a day, 365 days a year. This means that it is unacceptable to bring down a system or the entire network to perform backup operations. Application performance and availability. Traditional backup processing degrades the performance of other applications running on the server, and frequently requires a dedicated window of time when the system is unavailable to end users. Off-host technology allows the backup to run against a copy of the production data on a different server. This removes the performance overhead of backup processing from the production server and eliminates the need for a backup window. Traditional Client Backup using Backup Exec and the Exchange Agent Off-Host Backup using Backup Exec Advanced Disk-Based Backup Option and Storage Foundation for Windows FlashSnap Client Client LAN Media Server LAN Media Server CPU and I/O Impact CPU and I/O Impact Veritas FlashSnap Mirror Figure 3. Off-Host Snapshot Backup vs. Traditional Backup Creating snapshots for off-host backup requires minimal overhead and does not interfere with normal system operations. As a result, administrators can schedule snapshots frequently, minimizing potential data loss during a disaster. Off-host backups are a particularly good solution for organizations with stringent high availability requirements and large amounts of data. 10
LAN Exchange Server 2003 Backup Server Primary Mirror Storage Tape Library Exchange Data Flow Mirror mounted on backup server Backup data flow Disk Array SAN Figure 4. Common SAN Configuration Deployment information Backup Exec Media Server Symantec Advanced Disk-Based Backup Option Symantec Backup Exec Exchange Server Agent Veritas Storage Foundation 4.3 for Windows Shared SAN Storage, Hardware Arrays, or JBODs Exchange Server Microsoft Windows Server 2003 with SP1 Microsoft Exchange Server 2003 with SP1 Symantec Backup Exec Remote Agent for Windows Veritas Storage Foundation 4.3 for Windows Veritas FlashSnap Option Tape Library Figure 5. Symantec Backup Exec Quick Recovery and Off-Host Backup Solution 11
Software components Exchange Server Microsoft Windows Server 2003 SP1, Standard, Enterprise, or Datacenter Edition Microsoft Exchange Server 2003, Service Pack 1 (Service Pack 2 recommended) Symantec Backup Exec Remote Agent for Windows Servers (included with purchase of Symantec Backup Exec Agent for Microsoft Exchange Server) Veritas Storage Foundation for Windows Veritas FlashSnap Option SQL Server (not pictured) Microsoft SQL Server 2000 SP4 or Microsoft SQL Server 2005 SP1 Symantec Backup Exec Remote Agent for Windows Servers (included with purchase of Symantec Backup Exec Agent for Microsoft SQL Server) Veritas Storage Foundation for Windows Veritas FlashSnap Option Backup Exec Media Server Symantec Backup Exec for Windows Servers (Version 11d recommended) Symantec Backup Exec Agent for Microsoft Exchange Server (Version 11d recommended) Symantec Backup Exec Agent for Microsoft SQL Server (Version 11d recommended) Symantec Backup Exec Advanced Disk-based Backup Option (Version 11d recommended) Veritas Storage Foundation for Windows (Version 4.3 MP1 recommended) 12
Deployment best practices The VSS provider selected for snap (software or hardware) must be installed on both the application server and the media server. This means that Veritas Storage Foundation for Windows 4.3 MP1 or later must be installed on both the Backup Exec server and the Exchange Server and/or SQL Server system that it is protecting. Fibre Channel and iscsi SANs are both supported with this solution. The system and boot volumes should reside on a separate disk (Harddisk0). Using VSS, Microsoft Exchange Server supports snapshots at the Exchange Storage Group level only. The hardware for the snapshot solution should include sufficient storage to be able to create dynamic volumes on separate disks for the following purposes: Databases Transaction logs Split-mirror snapshots of the database stores and transaction logs volumes Exchange Storage Group databases and transaction logs can be located on direct attached storage (SCSI or ATA disk drives), or located on any SAN-based storage array or JBOD. Quick recovery snapshots can be located on direct attached storage (SCSI or ATA disk drives) or located in any SAN-based array or JBOD. Off-host backup snapshots must be located on SAN- or iscsi-based shared storage accessible by both Exchange Server and the Backup Exec media server. The initial Exchange Snapshots should be set up the first time during times when there is low system activity. This initial SnapStart operation through Storage Foundation for Windows is a one-time event that can be a lengthy process. Database stores and transaction logs for each storage group must be stored on disks contained within a single dynamic disk group. Each database should be in a separate volume, but the volumes may share the same dynamic disks. To enable independent recovery, mailbox stores and public stores should be on separate volumes. Database stores and transaction logs must be in separate volumes in order to perform a roll-forward recovery to the point of failure. Database stores and transaction logs should be on separate disks so that disk failure does not affect both the database stores and transaction logs. All SQL data and log volumes must be transportable. 13
Transaction logs should always be configured in a redundant layout. The preferred software layout is RAID 0+1 (mirrored striped) volumes as this provides better read and write performance than RAID 1 (mirrored) alone. The transaction log will generate the most I/O and thus should use the highest performance disks available. The preferred layout for the database stores is hardware RAID 5, software RAID 1 (mirrored with logging enabled), or software RAID 0+1 (mirrored striped). Note that FlashSnap is not supported for software RAID 5 volumes. No more than six volumes should be associated with a storage group. One volume should contain the transaction logs, and up to five other volumes may contain databases. By default, the First Storage Group is mapped to the boot drive. The boot drive cannot be snapshotted. Move the components of the First Storage Group to new volumes that are not on the boot drive. Create a unique name for the metadata file of each shadow copy set that is created and maintained. Periodically back up metadata files to ensure that they will be available for recovery. For quick recovery solutions, Symantec recommends creating or refreshing a shadow copy set immediately after a full backup just after the database has been checked for corruption and the transaction logs have been truncated. This process assures an image of a clean database. Additionally, to create another shadow copy set after an incremental backup, use a separate set of disks rather than refreshing the shadow copy set taken after the full backup. This practice prevents a shadow copy set of a clean database from being overwritten with an image of a potentially corrupted database. Limitations Off-host backup is not supported for differential or log backups of SQL databases. If off-host is used with the Backup Exec Central Admin Server Option, off-host backup jobs must target Backup Exec media servers that have Storage Foundation for Windows software installed on them. Restores are always done on-host back to the original Exchange Server or SQL Server system. Off-host restores are not supported. 14
Clusters: In a clustered setup, the media server and application server must not be in the same cluster group. This applies to both Veritas Cluster Server and Microsoft Cluster Services (MSCS) Exchange Server or SQL Server clusters. These clusters cannot support LUNs with duplicate signature and partition layout. The snapshot LUNs must be transported to a host outside the cluster. It is strongly recommended that Storage Foundation for Windows volumes be backed up using the ADBO off-host option reside in disk groups with either the private protection or cluster disk group disk group property. Private dynamic disk group protection and cluster disk group property settings use hardware locking techniques to protect a dynamic disk group located on shared storage from access by other hosts connected to the shared storage pool. A Backup Exec job cannot mix basic volumes with dynamic volumes in an off-host job. This restriction specifically applies to dynamic volumes mounted by mount points on basic volumes this configuration is not supported. For more information Symantec Backup Exec for Windows Servers www.veritas.com/products/www?c=product&refid=57 Symantec Backup Exec Advanced Disk-based Backup Option www.symantec.com/enterprise/products/agents_options_details.jsp?pcid=1018&pvid=57_1&aoid=368 Veritas Storage Foundation for Windows www.veritas.com/products/www?c=product&refid=31 Veritas Storage Foundation FlashSnap Option www.symantec.com/enterprise/products/agents_options_details.jsp?pcid=1019&pvid=31_1&aoid=261 15
About Symantec Symantec is a global leader in infrastructure software, enabling businesses and consumers to have confidence in a connected world. The company helps customers protect their infrastructure, information, and interactions by delivering software and services that address risks to security, availability, compliance, and performance. Headquartered in Cupertino, Calif., Symantec has operations in 40 countries. More information is available at www.symantec.com. For specific country offices and contact numbers, please visit our Web site. For product information in the U.S., call toll-free 1 (800) 745 6054. Symantec Corporation World Headquarters 20330 Stevens Creek Boulevard Cupertino, CA 95014 USA +1 (408) 517 8000 1 (800) 721 3934 www.symantec.com Copyright 2007 Symantec Corporation. All rights reserved. Symantec, the Symantec logo, Backup Exec, FlashSnap, NetBackup, Veritas Storage Foundation, and Veritas are trademarks or registered trademarks of Symantec Corporation or its affiliates in the U.S. and other countries. Microsoft, Windows, and Windows Server are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries. Other names may be trademarks of their respective owners. Printed in the U.S.A. 1/07 10753265