GoldenGate for Business Continuity Using Data Synchronization for HighAvailability July 2003

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Table of Contents Industry Perspective ........................................................................ 3

Business Continuity & Disaster Recovery ....................................... 3 Data: The Core Asset...................................................................... 5

Choosing The Right Data Availability Solution ............................. 5 Tape Backup ................................................................................... 5 Electronic Vaulting........................................................................... 6 Mirroring & Shadowing .................................................................... 7 Data Synchronization ...................................................................... 8 At a glance comparison................................................................... 9

Data Synchronization From GoldenGate ..................................... 10 GoldenGate Components (Capture/Delivery)................................ 11 GoldenGate Environments ............................................................ 11

Conclusion...................................................................................... 12 About the Author: .......................................................................... 12

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Industry Perspective The concepts of disaster recovery planning and business continuity planning have been part of the corporate landscape for as long as companies have relied on automated information technology systems. Within many organizations, however, these initiatives remained largely the concerns of IT departments or technology groups. And in many other organizations, business continuity was ignored altogether. In fact, a recent Gartner survey of IT managers found that more than 60 percent of businesses had no disaster recovery plans in place at all. Other Gartner surveys found that:

• Half of all businesses that are impacted by a disastrous event are out of business for two weeks following the event.

• Two out of five enterprises that experience a disaster will no longer be in business five years after the event.

As these numbers make evidently clear, outages in key business systems can severely impact productivity and ultimately the viability of the enterprise itself. This white paper examines the risks that today’s enterprises face, and the types of remediation or mitigation measures that organizations should take in order to ensure business continuity. It also describes in detail GoldenGate’s Data Synchronization solution, and demonstrates the reasons why the GoldenGate approach to business continuity and disaster recovery is superior to other methods.

Business Continuity & Disaster Recovery Though often used interchangeably in conversation, business continuity and disaster recovery are distinct concepts. Continuity is the quality or state of being continuous, an uninterrupted succession or unbroken course. Therefore, business continuity is the ability to effectively conduct business without interruption; or if there is an interruption, the ability to ensure that it is of such short duration as to not have any adverse effect on the business. Disaster recovery, on the other hand, refers to the ability to restart business processes after the occurrence of a system outage. Disaster recovery is essentially a response to an event whereas business continuity must be viewed in terms of the overall business need. The major components of business continuity are people, property and equipment, systems and data. Without the data, there is no recovery and certainly no continuity of the business. This is especially true in sectors that have become heavily reliant on network and e-business technologies, such as financial services, banking, telecommunications, healthcare and retail. As mentioned above, disaster recovery and business continuity have traditionally been exclusive to the technology groups within the organization. A major reason for this was that the theory, practices and terminology behind both formed around

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relevant infrastructures. For instance, Recovery Time Objectives (RTO) are based upon the impact of an interruption in information systems (IS) services to key business processes and/or functions, and Recovery Point Objectives (RPO) are based upon the critical nature of data currency. Today, however, with business units in the organization becoming much more sensitive to the continuous availability of information and processes, the impact of an interruption of IS services needs to be explained in business terms, not just in techspeak. With that in mind, consider RPO and RTO redefined in business terms:

• RPO – The maximum allowable age of data available, which when exceeded will adversely impact the accuracy, integrity and reliability of the information used or produced by the business units.

• RTO – The maximum period of time in which business processes can be unavailable before adversely affecting the goals and objectives of the organization.

Let’s apply these terms to the real world. What would be a reasonable RPO and RTO for a bank with a large ATM/POS network? Such networks can support tens of thousands of transactions per minute, and that includes both cash deposits/withdrawals as well as in-store purchases performed with bankcards. A bank that handles 15,000 transactions per minute will lose as many as 250 transactions per second during an outage, and with every passing second the age of the information increases. In an industry where trust and security are paramount concerns, such a failure could be catastrophic. Which is why for many banks the RPO and RTO on crucial systems such as an ATM network is zero. In other words, the business will be adversely impacted if ATM data ages and the system is unavailable for even one second. A situation such as this requires a business continuity plan (BCP) incorporating a disaster recovery infrastructure that could instantly restore the ATM system to full functionality without the loss of any data. This would necessarily entail

a) A backup system with the ability to capture and backup transactions as they happen

b) Procedures, measures and systems to ensure that this secondary system would instantly take over in the event of a disaster

In contrast, the RPO and RTO for less crucial enterprise applications (such as email or an analytical system, for instance) are likely to be somewhat less demanding. Of course, an interruption in email service can adversely affect business, but it is far less likely to result in catastrophic financial losses. Seen in the context of an overall business continuity plan, disaster recovery for email need not be as robust. Management’s understanding of these concepts and terms, and not just in banking but in many other industries also, are essential to

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formulating effective disaster recovery solutions that can ensure business continuity.

Data: The Core Asset With the bank ATM network example we see that business continuity today is often best understood in terms of data. The Internet and enterprise IT initiatives such as ERP and CRM, along with the growing abundance of inexpensive storage products, have dramatically increased the amount of data that the enterprise must manage. What’s more, as organizations age and add to their installed base of technology systems, enterprise data becomes increasingly diverse with respect to hardware platform, operating systems and databases. This holds true across nearly every major sector, from financial services, retail, telecommunications/media, healthcare, government, technology and so on. And as essential business processes become more automated in all these industries, so does it become increasingly important to maintain availability to this data. In fact, seen in light of business continuity, it is safe to say that data availability is the key to attaining both RPO and RTO. Which directly leads to the most important question confronting CIOs, vice presidents of IT and other executives responsible for business continuity: what is the most secure and efficient means or technology for protecting your data and ensuring its availability across the enterprise?

Choosing The Right Data Availability Solution As long as organizations have relied on data, so have they sought to protect their data. Tape backup and disk mirroring have traditionally been the most popular solutions for keeping data safe, but the landscape has changed significantly in recent years as newer technologies have emerged. Rather than relying on data backup simply for disaster recovery, more and more organizations today are seeking a robust replication topology to reduce or even eliminate outages in data availability that are both unplanned and planned. This ultimately means that mission-critical applications can continuously generate revenue and improve the company’s bottom line regardless of interruptions. That central premise should be the focal point of any business continuity planning. Let’s consider the strengths and weaknesses of several of the most widely used technologies.

Tape Backup Despite the fact that it has been around since the early days of computing, tape backup continues to maintain its status as a vital disaster recovery technology and a key element in the business continuity strategies of organizations worldwide. According to Gartner Dataquest figures, the total industry expenditure for tape drives in 2001 was US$2.62 billion. This was a significant decline from 2000 figure of US$3.01 billion in 2000, but seen in the context of the

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overall drop-off in post dotcom IT spending it was still an impressive number. As Gartner puts it, the reason that tape endures as the most popular data backup technology is that tape drives continue to deliver “the lowest cost per megabyte stored.” But while tape is relatively inexpensive, it is also labor intensive. In a traditional off-site archiving scenario, also known as physical offsite vaulting, a dedicated administrator is needed to execute the copying process for whatever application is determined to warrant backup. When the backup is finished (once a day is a typical scenario), the tape must be physically removed from the drive, packed and then shipped to a storage facility located a “safe” distance from the production system. Libraries of tapes must be scrupulously maintained and indexed in order to provide for quick retrieval in the event of a disaster. It’s a process that presents numerous drawbacks. With each manual step the potential for mistakes or mishaps increases, from car accidents to simple human error. Moreover, tape is far from ideal in terms of data integrity because it provides only a “point-in-time” snapshot of enterprise data. If backup is performed every night at midnight, the organization could potentially be without a whole day’s worth of data as it waited to retrieve the appropriate tape. And what happens when a disaster is declared? The administrator needs to gather all tape out of storage, determine which ones have the pertinent data, and then begin reloading them into the tape drives at the production site. It’s a cumbersome process that takes a long time, which inevitably leads to a large downtime window. Many organizations rely on third-party tape library services, which can expedite the disaster recovery process. But in the event of a geographically widespread disaster such as a flood or an earthquake, library or vaulting services are likely to be inundated with multiple claims from their client organizations in the affected areas. The more client firms they have in the area, the longer the recovery time is likely to be for all involved.

Electronic Vaulting Electronic vaulting (EV) uses network technologies to create backups at off-site facilities, usually with tape though disk mirroring data replication can also be used. Because the data is transmitted electronically, there is no need to physically process and deliver tapes via car or truck. The benefits over traditional physical offsite vaulting are clear: network transmission is faster, backups are created continuously and the vulnerabilities of moving tape from one location to another are eliminated. For these reasons EV has gained popularity over the years, but the technology does have certain disadvantages. First, EV is a volume replication technology: data is copied in blocks as they change on the source hard drive. The result is that if data is corrupted on the primary system, that corrupted data will in turn be replicated to the backup.

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During a disaster recovery situation this corrupt data could present significant problems. Moreover, if tape is being used as the backup environment, all of the negatives inherent with the medium noted above still apply. The appropriate tape must be located, transferred from tape back to disk and then the application environment must be rebuilt. Delays in getting your business back up and running are simply unavoidable. Where EV service providers rely on volume/disk replication, there are rigid requirements for highly mirrored primary and backup systems. In disaster recovery situations, volume/disk generally provides adequate coverage, yet copies are typically not accessible during replication—a potentially significant issue in instances where large amounts of data are being copied. Also, volume/disk replication relies on additional hardware, which can lead to greater expense that is inevitably passed along to the customer. As a result of all these concerns, EV is considered effective for cold site scenarios, but not where data availability needs are high and RTOs are short.

Mirroring & Shadowing Mirroring has long been considered the gold standard for maintaining optimum data availability and supporting the most demanding business continuity plans. Using synchronous or real-time volume/disk replication, mirroring continuously copies data between two geographically dispersed storage systems, in most cases via dedicated high speed connections. This method ensures that two or more exact copies of enterprise data are readily at hand at all times. Again, as with EV, the advantages over tape are obvious. Labor is minimized and physical transport issues are done away with. Moreover, in a disaster situation the backed-up data is available for immediate failover, so it is possible to avoid any downtime at all, even during a catastrophic event. The enormous expense of deploying and maintaining mirrored backup systems, however, makes them untenable for many organizations. Whereas off-the-shelf tape backup systems can be purchased for a few thousand dollars or less, a mirrored backup solution requires two identical systems, with no deviation in the configuration. It is not an option to go outside like-to-like hardware platforms, operating systems and databases (if you’re on Oracle 9i, your secondary has to be Oracle 9i.) Because of these hardware and software considerations, mirroring an enterprise-scale storage array or production mainframe can easily reach into the millions of dollars. In addition, because most mirroring replication schemes copy and write data at the volume/disk block level they are prone to block corruption. To guard against this type of corruption triple mirroring software is required, which adds to the expense. Furthermore, traditional mirror-based SAN disaster recovery solutions are in some cases constrained by the latency issues present with fibre channel, the high-speed transport technology used to connect SAN enclosures. In effect,

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the longer the fibre channel connection between SAN enclosures, the greater the latency, which can have a deleterious effect in disaster recovery scenarios. A technology that is similar to but distinct from disk-level mirroring is software-based volume replication. Using the same kind of replication logic as mirroring (data is copied as volumes) software-based volume replication frees the user in some cases from having to create an identical secondary system and configuration. With the ability to create a back-up system using off-the-shelf components, organizations get volume/disk-level replication quality at a much lower price point. In addition, this method works with IP networking technologies, providing further cost benefits. On the minus side, the added software layer results in more intensive use of network resources, which can have a negative impact on replication volumes and speeds.

Data Synchronization In recent years a fourth technology has gained popularity as a platform for data backup and business continuity planning. Known as data synchronization, this software-based technology optimizes data movement, availability and management through sub-second capture and delivery of large volumes of changing data across diverse environments. While providing a low impact mechanism for the capture and delivery of data, data synchronization can transport large volumes of data quickly and efficiently to remote systems via LAN or WAN with uncompromised accuracy. Data synchronization software maintains the transaction sequence and context as well as the read consistency from source to target instance, so that the target tables and sequences are updated exactly as they are on the source system. Not only can data synchronization deliver data to the secondary system in a read consistent manner, the system can also be tuned and configured to optimally support the desired application as it pertains to performance and throughput. Unlike disk mirroring, data synchronization software is not dependent on the source hardware, operating system or database. If the customer wants to create a synchronized or backup instance and, for example the source system is Oracle running on a Sun server, the target could be a LINUX server running MySQL with table structures and indices specific to the reporting instance, or any number of other OS/database configurations. The result is that backup copies of all your most critical data are available for nearly instantaneous failover in the event of a system outage. In effect, data synchronization delivers fundamentally all of the benefits of volume-disk and software-based volume replication with the added flexibility of system diversity: users can replicate data between systems with unlike operating systems and databases. In addition, by providing a host of data management capabilities data synchronization has positive implications far beyond simple disaster recovery. Consider the issues of data usability. It is often difficult to justify the additional hardware and software needed to build recovery solutions.

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Although it is important for all mission critical systems to have an insurance policy in the event of a disaster, material benefits are difficult to calculate when investing in redundant enclosures that typically sit idle waiting for a disaster to occur. For instance, when you replicate 100 gigabytes to a secondary network storage enclosure, those 100 gigs on both sides simply resides as volume-based data. There is no way to get a good view into the data because it is being replicated and formatted in blocks. Whenever any aspect of a particular block is changed, it is then replicated to the secondary site. You cannot tell if changes have been made to a single file, whether someone has moved a file or a group of files. With data synchronization however, replication happens at the transaction level, which provides unparalleled visibility into your data. This granularity makes data synchronization an excellent solution not just for disaster recovery and business continuity planning, but also for other initiatives such as:

Business Intelligence Integration • Data warehousing and data marts • Business activity monitoring • Operational data stores

Application Integration

• Consolidation • Data collaboration • CRM and supply chain

Operations Optimization

• Data migration • Database conversion • Load balancing

At a glance comparison Data

Availability Data

Protection Low Cost and

Low TCO Low Resource Requirements

Networking Capability

Tape Backup

N/A

Electronic Vaulting

N/A

Volume/Disk Mirroring

Data Synchronization

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Data Synchronization From GoldenGate GoldenGate pioneered the technology that has come to be known as data synchronization: the sub-second capture, transformation and delivery of large volumes of data across heterogeneous IT infrastructures. Predicated on the three-point ideal of speed, volume and diversity, the GoldenGate 7 Software Platform provides a single solution for achieving sub-second disaster recovery within virtually any enterprise environment. The following are some key features that distinguish GoldenGate’s data synchronization software:

• Native Change Data Capture – As a log-based synchronization solution the impact on the source system as well as the network is minimized

• Flexibility – Source and Target system do not have to have similar operating systems, hardware, disk configurations, databases and schemas (e.g. table structures, indexes, etc.). GoldenGate can also replicate between instances on the same system, to instances on a local area network, or to remote instances through a wide area network

• Migration without Downtime – GoldenGate can synchronize between different versions of the database and operating systems. An upgrade of the database, operating system or application can be performed on a secondary system. Once the upgrade has been fully tested, processing can be switched to the secondary system and upgrade the primary system. Once the upgrade completes the primary can be brought in sync with the secondary system without a system outage.

• Hardware and Database Independence – GoldenGate is operating system, database and hardware agnostic. Data can be moved between various environments, thereby eliminating the customer’s dependence on any one topology.

• RPO and RTO Objectives – GoldenGate facilitates instant recovery to backup because both the source and target can be configured/architecturally designed for bi-directional “peer-to-peer” capability.

• Bi-directional Replication – GoldenGate provides the ability to have two or more live systems all replicating to one another. The systems do not have to have the same characteristics or be of like operating system, database or database version.

• Data Consistency – The backup database can support read-consistent query activity (transaction integrity is preserved at all times).

• Flexible Topology – Assorted data distribution options are available at the database and table level. For example: one-to-many, many-to-one, many-to-many, and cascading scenarios are all supported.

• Mapping and Transformation Capabilities – Column transformations are possible to accommodate unique backup requirements, including lookup and the execution of stored procedures.

• Data Selectivity – Selected data, such as tables, rows and columns, can be replicated, rather than entire volumes.

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• Oracle Real Application Cluster Support (RAC) – A unique requirement specific to Oracle is the real-time support for RAC replication. Different from other approaches available today is the ability to capture and deliver data from online transaction logs.

GoldenGate Components (Capture/Delivery) Source D/B

DDeelliivveerryy LAN / WAN / Internet CCaappttuurree

Queue Transaction Log

Target D/B

GoldenGate Environments GoldenGate’s GDS Platform runs on today’s most popular databases, operating systems and hardware platforms: DATABASES OS/HARDWARE PLATFORMS Oracle UNIX DB2 Windows NT/2000/XP Microsoft SQL Server Linux Informix HP/UX Sybase IBM AIX Teradata Tru64 IMS/VSAM OS/390 z/OS MySQL OS/400 TimesTen Linux HP Non-Stop SQL MP SCO HP Non-Stop SQL MX VMS Enscribe Siemens All ODBC Compatible Databases For a more detailed technical overview of GoldenGate Data Synchronization please refer to the white paper GoldenGate Technical Overview, downloadable from our website at www.goldengate.com

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Conclusion Designing a cost-effective, continuously available environment for your enterprise applications requires that you understand the causes of outages in your organization and how disruptions impact your business in terms of downtime costs per hour, day, week, etc. Data Synchronization offers the opportunity to guarantee continuous access to the information that is vital across the enterprise. Business Continuity is extremely vital for a company’s prosperity. So much so that it can no longer remain the regard of IT departments alone. No matter the size of the company, any business disruption where there is a time, money or loss of customer confidence component associated with the downtime will have negative implications not easily regained. The peril for companies where customers demand 24/7 access to the business, exposes them to even greater vulnerability. To guarantee survivability, companies must select proven strategies to preserve both vital information and business processes and implement enterprise-wide solutions for continuity and recovery management GoldenGate is the “One Investment One Platform” solution for your entire enterprise that provides both technical adaptability offering speed, volume and diversity, as well as a low total cost of ownership, ultimately offering you the key to solid business continuity.

About the Author:

Warren T. Cross - Global Technology Director, CBCP

Warren has over 20 years of experience in the field of Computer Technology working with a diverse range of industries to include, Banking, Defense, Government, Insurance, Manufacturing, Retail, Software Development and web technology firms. Warren has created technology and practical business solutions with special emphasis on business contingency operations planning and disaster recovery preparedness. With degrees in Computer Science for Business and Computer Information Systems along with certification by DRI International’s Certification Commission he brings the technical, operational and business methodology needed for deploying high availability enterprise solutions.

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