|introduction by Zsolt Kerekes,
Network connected disk to disk backup systems for the enterprise have come a long way since the first pioneering products started to appear in the pages of StorageSearch.com in the late 1990s.
Some of the growing sophistication in the market can be seen by the way that the marketing terminology has morphed from the early D2d (let's kill tape backup), via D2D2T (let's be friends with tape / peaceful coexistence) to the current VTL (Virtual Tape Library - let's just see if they notice that it's more reliable and works faster - and don't tell them that there isn't a tape in the box) type of approaches.
But if you think that speed, reliability and cost are the only things you need to know about the "virtual" versus "real" tape library argument - take a look at this comprehensive article from MaXXan Systems which shows there are a lot more benefits than that.
Virtual Tape: Can You Afford to Ignore It?
|The advent of new,
lower cost disk-based technologies also brings with it a variety of new ways of
solving old backup problems. The terms, D2D (disk-to-disk) and D2D2T
(disk-to-disk-to-tape), are becoming more common nomenclature to describe the
various disk-based methods available to address the common data protection
issues experienced by many of today's organizations. Virtual tape is one method
gaining significant user interest, primarily due to its ease of implementation
and management within existing tape-based infrastructures. This white paper
attempts to answer reader questions about whether or not virtual tape is the
right disk-based technology for their own needs and environments. It describes
some of the common benefits of virtual tape, along with how it compares to
other, host-based backup methods, such as backups performed directly to disk.
Lastly, readers will learn of some ways virtual tape libraries are being used in
today's data center, along with some of the unique characteristics to be found
in MaXXan's own virtual tape solutions.|
IT Issues Influencing the Move to Virtual Tape Architectures
IT managers charged with overseeing their company's data protection efforts are in a tough position. Many find themselves actively waging an uphill battle to back up and protect the growing mountain of company data they face each year. At the same time, a new spate of compliancerelated legislation has left many IT managers with the task of adopting more stringent backup and disaster recovery-related practices that stress rapid access to older data -- at often a moment's notice. In their effort to keep up with these types of growing backup needs, however, data centers often run up against the limitations of their IT staff resources and the constraints of their own tape-based backup architectures. This chart from Enterprise Strategy Group shows the percentage of users who are encountering various problems with their current backup and recovery solutions.
|The following table describes some of the most common issues that make it difficult to achieve affordable, robust data protection goals:|
|Combined, these factors have
begun to put a serious strain on many already taxed tape-based backup
For these reasons, most IT groups have begun to look seriously at implementing some form of disk-based backup solution to alleviate many of the current pain points surrounding their reliance on tape. Virtual tape libraries (VTLs) are one class of disk-based backup solution that has been gaining momentum among IT managers for their ease of deployment and simple integration into existing tape infrastructures.
How Virtual Tape Works
To understand why VTLs have become an increasingly popular choice for backup, it's important to first understand how they work. Virtual tape libraries do just what their name implies: They emulate industry-leading physical tape drives and libraries, presenting themselves as tape to all of the common backup software applications -- even going so far as to assign appropriate bar codes to each virtual tape "cartridge" used by the backup software.
In actuality, while backup streams are being sent from a backup media server to a virtual tape library, the VTL is hard at work behind the scenes, writing the data sequentially in native tape format to some form of disk storage. Although it appears just like another automated tape library, the use of disk will cause administrators to see their backup jobs completing up to 10 times faster.
In the case of VTL solutions like the MaXXan SVT virtual tape standalone appliance (or its counterpart, the SVT application card for integration with the MaXXan MXV switch), this data can be exported from the virtual tape appliance to physical tape for off-site vaulting purposes. (See Figure 2 below - How Virtual Tape Works).
|Some benefits of this export
process include the fact that exports to tape can now be completed at a later,
more convenient time that won't impact production schedules. The export process
from the MaXXan virtual tape appliance has also been engineered to make the most
efficient use of the storage available in each tape cartridge, increasing tape
utilization rates by as much as 50% or more.
In the case of MaXXan SVT systems, the end result is amazingly fast backup and data restore rates. It's common to see MaXXan VTL-based backups complete up to 10 times faster than their traditional tape counterparts -- with zero media defects or mechanical failures. Restore times can also occur in seconds versus the hours spent with traditional restore-from-tape scenarios. Restores even have the option of being user-directed, which can serve to free up administrator overhead.
The Benefits of Using Virtual Tape Libraries
Virtual tape libraries have become an increasingly popular choice for companies striving to realize the performance benefits of disk-based backups and restores, while at the same time protecting the investment of time and money they've already made in their tape-based infrastructures.
Today, virtual tape appears to be finding a home in both enterprise data centers and mid-level organizations. Findings from one survey of IT managers report that as many as 23% of enterprise respondents have already deployed virtual tape in their environments.
This number appears to be growing substantially as well, given the results from another survey of high-level enterprise IT managers. TheInfoPro, also placed virtual tape among the top five storage networking technologies to watch in the firm's "Technology Heat Index." The Heat Index is a proprietary index that prioritizes the importance of more than 20 different storage networking technologies based on whether or not a majority of IT managers interviewed have already invested in the technology, or are planning to do so in the short term.
Many of today's IT managers have already made the decision to invest in virtual tape libraries. The following table lists just a few of the primary reasons VTLs are gaining a stronghold in today's IT environments.
|How to Seamlessly Implement
MaXXan SVT Systems in Your Environment
The concept behind virtual tape libraries may sound intriguing to readers who struggle with many of the same issues as earlier outlined. IT managers may still have valid concerns, however, about the amount of disruption and work involved in introducing any disk-based technology into their existing environments.
Backup teams in robust enterprise environments routinely spend as long as a few years tuning their backup environments and third-party backup software applications, adding custom backup scripts and creating workflows to manage hundreds or thousands of individual tapes.
Faced with the high incident of tape media failures and the growing risk of disasters that might require faster restores than allowed by tape media, IT managers are faced with a decision. They need to move to new ways of doing things, while at the same time protecting the investment they've already made in their tape-based infrastructures.
This is one of the main reasons for customer interest in virtual tape systems. Since they emulate physical tape drives, tape libraries and tape cartridges, they can be seamlessly added to existing environments -- without disruption to current processes, procedures or workflows. There's no need to change out or reconfigure existing backup software processes, for example.
The backup software sees the VTL as if it were a physical tape. The only thing IT managers will notice in its operation is significantly faster backup and restore speeds. Users can also quickly connect the VTL to existing tape libraries.
Exploring VTL Deployment
Comparing Virtual Tape Libraries to Other Disk-Based Backup Methods Using the MaXXan SVT appliance as an example, let's explore how quickly these types of virtual tape solutions can be deployed in existing tape environments. Typical installations of a MaXXan SVT appliance usually take the customer just 20 minutes to complete. This is because the SVT systems are built for simplicity -- from initial deployment straight through to their on-going system management functions. Very little preparation work is required before the SVT system is ready to read and write existing backup data streams to disk. The only real work involves adding another server to the network; namely, giving the MaXXan SVT device an IP address and a host name.
Then, using MaXXan's Web-based interface, you just configure the appliance as a new tape drive or automated tape library, and you're in business. All you now have to do is go into the backup application software provider's management console and reassign any designated backup stream to the new location. IT customers exploring the use of disk in their backup architectures may also look at the prospect of using just their current backup software application, with some type of built-in disk staging or cloning functionality, in conjunction with a less expensive ATA- or SATA-based disk system.
This method is often referred to as host-based D2D (disk-to-disk) or backup direct-to-disk.
Readers may wonder how this type of disk-based backup method compares to the use of a virtual tape library.
While both methods allow for faster writes and restores of backup data from disk, host-based D2D can involve significantly more barriers to deployment than VTLs. In order to deploy these types of solutions, customers typically need to address the added complexity they bring to existing environments. This complexity often requires the need to:
While most companies implement VTLs to improve their backup/restore performance, another powerful benefit has emerged to their use. Comapnies are also seeing a dramatic reduction in their per-server license fees paid to backup software providers. Here's how it works: VTLs like the MaXXan appliance can be configured to reflect a smaller number of virtual tape drives and libraries than the customer's current tape-based configuration. The VTL, however, still meets existing storage capacity requirements by configuring each virtual tape as a larger size tape within the VTL.
For example, using a MaXXan SVT appliance as a gateway that sits between a Veritas NetBackup media server and an ATL containing 20 tape drives, you could configure the MaXXan appliance to emulate one library with 4 larger tape drives. Without the MaXXan appliance, the customer would typically pay for 20 tape drive licenses. With the appliance, they now have to pay for only 4 tape drive licenses.
|How Virtual Tape Can
Improve Disaster Recovery for Remote Offices
Some organizations have multiple remote offices where it can be a challenge to ensure adequate backup and data protection efforts. Usually, this is due to the fact that there are seldom dedicated IT staff on the premises to monitor backup operations to physical tape. What often results is tape media that is misplaced or mislabeled, and spotty backup procedures that can leave critical remote data at risk in the event of a disaster.
Virtual tape libraries from MaXXan Systems offer an interesting alternative to this dilemma that allows IT managers to be assured of centralized backup control and DR protection for their remote data.
With one MaXXan SVT appliance at the data center and another appliance installed at a remote location, the dependence on physical tape at that remote site is now removed. (See Figure 3 below.) The data center can now take advantage of the MaXXan SVT system's remote replication features to move data over IP from the remote SVT standalone appliance to the MaXXan SVT system located back at the company's centralized data center. Remote data can then be exported to physical tape at the data center's SVT system for added protection.
|Using Virtual Tape for
Off-Site Disaster Recovery and Remote Vaulting
As a derivative of the above scenario, customers are also using the remote replication functionality in virtual tape to better automate and protect the process of getting their data off-site. Traditionally, customers have been accustomed to backing up their data to tape, then frequently shipping the tapes off to a remote archival or deep vault facility for long-term storage and added disaster recovery protection. The need for off-site disaster recovery and long-term tape archival is even stronger today, thanks to a host of compliance-related regulations that routinely require IT organizations to maintain off-site copies of key data for certain lengths of time.
With MaXXan SVT virtual tape systems, customers can now install one appliance at the central data center and another appliance at the remote DR site. The appliance at the remote site is usually directly attached to an automated tape library. With this configuration, customers can again take advantage of the remote replication features of their SVT systems to move tape from the data center to the off-site vault without requiring the need to physically ship the tapes from place to place. Backup data is replicated automatically over IP, then exported to local tape at the remote DR site. This type of "remote vaulting" can eliminate costly delivery truck services, higher incidence of tape failures or missing tapes due to handling, etc.
Virtual Tape and Regulatory Compliance: New Solutions for New Challenges
The era of digital data has posed new challenges for government bodies who seek to protect the joint interests of customer privacy and data security. The result has been a growing volume of federal and state legislation that requires companies to prove that they are adequately securing, storing and archiving regulated data so that it can be made readily available for auditing purposes or as a result of immediate legal or court request.
Compliance has added a new burden to the shoulders of IT managers who are already struggling to back up and store the ever-growing amount of company data. Virtual tape libraries can simplify some of the issues in this dilemma by allowing the majority of regulated data to remain on disk, as well as being exported to tape. If a need then arises for rapid restore of key data, administrators just need to access the proper "virtual tape" on disk and can usually restore specific data or files within just a few minutes.
Simply put, virtual tape libraries provide faster data access and a better performance alternative to support the compliance needs of today's IT enterprise. Virtual Tape and Regulatory Compliance: New Solutions for New Challenges
|The MaXXan SVT Advantage:
Speed, Remote Management, Reliability and Flexibility
MaXXan's family of virtual tape solutions brings a number of unique, differentiating features to market. These include:
Speed and Performance.
A survey by Enterprise Storage Group asked IT managers about the most important characteristics they looked for when evaluating disk-based backup technologies. At the top of their list was performance. This makes sense since most IT managers come to disk solutions in order to gain faster backups and restores.
Most virtual tape systems significantly surpass existing tape backup/restore speeds. It's not uncommon to see VTL solutions that conduct aggregate read/write operations at somewhere between 200 to 400 MB per second of sustained throughput. But, when backup windows are at a premium, it pays to use the fastest virtual tape library solution you can find.
The MaXXan SVT virtual tape systems are carefully designed with a unique, purpose-built hardware I/O engine designed for maximum speed and throughput. This means that MaXXan SVT solutions are able to achieve fast I/O throughput speeds:- 660 MB/sec for backups and 715 MB/sec for restores.
Innovative Design - MaXXan virtual tape systems come as either a standalone virtual tape appliance or as an application card that integrates into MaXXan's MXV intelligent SAN switch. MaXXan Systems, an industry pioneer in the development of intelligent SAN switches, has built a powerful switch-based architecture designed for the data center, which allows customers to quickly add other application cards to the switch, in order to perform added functions such as NAS gateways, or more robust disaster recovery and storage consolidation functions like snapshots and mirroring. With such a strong focus on switch-based intelligence, customers can be reassured that the products will also remain current with future advances in SAN speeds up to 4Gbps.
Non-proprietary approach - Many VTLs on the market choose to integrate disk into their VTL solutions. At MaXXan, we believe this limits the customer's choices regarding disk-based technologies. At MaXXan, we prefer to give customers the option of either adding their own disks, or purchasing a MaXXan appliance that includes its own disk array. That way, customers can choose to take advantage of existing disk storage they may already have, as well as being open to adopt newer disk technologies as they come to market.
Professional Services - In addition to hardware and software, MaXXan also provides professional services to ensure that the VTL is optimally configured for your environment and you'll gain the most rapid return from your investment.
Many IT organizations have already begun to enjoy the fast performance benefits of disk and reduced TCO inherent in virtual tape libraries. Is now the right time for your organization to explore the use of virtual tape in your environment? ...MaXXan Systems profile, Disk to disk backup