Optimizing your Tape Backup Strategy

Transcription

1 E-Guide Optimizing your Tape Backup Strategy Attention: Tape is not dead. This form of backup is still a preferred technology in SMBs which is understandable due to its low cost and long term archiving capabilities. And the recent advances in tape technology Linear Tape File System (LTFS) and LTO-5 prove the fact that tape is not going anywhere and that it should stay in your data center. Download this expert E-Guide to learn how to optimize your tape backup and recovery and criteria for choosing an offsite tape storage service. Sponsored By:

2 E-Guide Optimizing your Tape Backup Strategy Table of Contents Tape backup devices still used by majority of SMBs Offsite backup tape storage and choosing a tape vaulting service Linear Tape File System (LTFS) products seen as archiving boon Resources from Iron Mountain Sponsored By: Page 2 of 16

3 Tape backup devices still used by majority of SMBs By SearchSMBStorage Editorial Staff Tape backup devices are still a preferred technology in small- to medium-sized businesses (SMBs). According to a survey of 441 data protection professionals, Milford, Mass.-based Enterprise Strategy Group found that a tape-only backup strategy in companies with fewer than 1,000 employees is more predominant than in firms with more than 1,000 employees (by a 3:2 margin). In addition, recent advances in tape technology like the Linear Tape File System (LTFS) and the latest iteration of LTO tape, LTO-5, have boosted the appeal of using tape backup devices for data archiving. To help you get updated on the latest tape backup information, we've compiled our most recent news, tutorials and expert advice on tape backup devices in one place to help get up to speed quickly. The pros and cons of tape media storage for backup and recovery in SMB environments A major change in the enterprise data storage landscape over the past decade started once the cost per megabyte of tape storage became more than the cost per megabyte for disk storage. But tape still has its place in data backup and recovery for many companies, especially in small- to medium-sized businesses (SMBs). There are many advantages to using tape backup and tape libraries. For example, backup tapes can be removed and stored safely offsite. And tape cartridges can usually recover from drops and other damages that could make hard drives non-functional. Tape cartridges may even survive floods and other disasters that would wipe out systems based on disk storage. Also, in the case of a disaster, tape recovery services can be used to clean and dry tapes, and recover much of the data that was originally stored on them. In this tip, read about the pros and cons of tape storage, popular tape data storage technologies today, and how tape compares to other backup considerations in terms of reliability, cost and more. Sponsored By: Page 3 of 16

4 Longevity of tape media storage Tape cartridges may last for as long as 30 years if they are properly stored. In addition, many tape storage devices are backward compatible. For example, a tape written by a digital linear tape (DLT) drive, made nearly 20 years ago may be readable on recent DLT drives. Drives that can read nine-track tape from the 1980s are still available. And although many early tape formats are not well supported today, it is possible that tapes made today will be readable on future drives. Hard drive interfaces may not be as long-lived. The original, tiny capacity drives of the early 1980s that used MFM or RLL interfaces probably can't be read today because it is probably extremely difficult to find an old PC or a drive interface card that could read it. Parallel ATA (also known as IDE) drives are also well on their way to becoming dinosaurs. But SCSI has been around for more than two decades, and Fibre Channel (FC) has been in use for more than a decade, and they may continue to be around for a while longer. Serial ATA (SATA) is the new kid on the block, and drives as large as 2 TB in capacity are currently available, and it will probably be around for at least another decade. In general, for long-term storage and successful recovery of data, tapes may be the best option. Downsides of tape storage There are many reasons why SMBs may choose to use disk-to-disk backup instead of tape storage. Tapes are not random access like hard drives. If you want to restore a file that is at the end of a tape, the drive must go through the entire tape to find the file you want. If the data is on another cartridge, you have to eject the cartridge (or, if it's in a library with more than one drive, you have to load it into the other drive), and have the drive search for the file. In other words, tape may be a hassle for some people because it is slower than disk backup. Plus, the cost per megabyte of a tape cartridge and drive is often higher than the comparable hard drive backup. Today, terabyte hard drives are available for less than $100, and 1.5 terabyte drives can cost as little as $150. In contrast, LTO-3 tape cartridges, capable of storing 400 GB native (800 GB compressed) cost at least $25, when bought in large quantities. LTO-4 cartridges, with 800 GB native (about 1.6 TB compressed) cost around $40 or more, which in this case, may actually cost Sponsored By: Page 4 of 16

5 less than comparable hard drives. DAT72 tapes, with a raw capacity of 36 GB run around $10 each, and 20 of these cartridges, with a total capacity of 720 GB, would cost around $200. Depending on which technology you purchase, in most cases the cost per gigabyte of capacity for tape is usually higher than the cost for the SATA drives that form the basis of many disk-based data backup systems. Tape storage capacity is often less than disk storage capacity Tape cartridge capacities are smaller than the disk drives they'll be backing up. The latest LTO-4 tape drive only stores a total of 1.6 TB. The actual raw (uncompressed) capacity of this cartridge is 800 GB. For years, the tape industry has quoted capacities that reflect "compressed" storage. For text data and simple data files, the actual amount of storage may be more than double the raw capacity. However, if you're backing up already compressed files (i.e., ZIP, video, MP3, or JPEG images), these files won't be compressed. In other words, if you want to back up more data from your storage system than your tape can handle, you've got a few choices. First, you can have someone wait near the tape drive and, when prompted, switch out a blank tape to replace one that's already been filled with data. Or, you can get a tape library that can automatically remove a full tape and retrieve a blank tape from a storage slot in its enclosure, and load the tape into the drive. Similarly, the robot can automatically switch tapes to the appropriate volume when restoring files from the tape system. Popular tape data storage technologies today Over the years, many tape storage technologies have fallen out of favor and the industry has focused on two: LTO and DAT. LTO tape drives have a higher capacity than DAT, and use half-inch tape inside the cartridge. LTO drives are larger than DAT and in most cases, the drives and libraries are more expensive than DAT. The latest version of LTO is LTO-4, and the cartridges are capable of storing up to 800 GB of raw data (and about 1.6 TB of compressed data). Raw data transfer rates of up to 120 MB/sec are possible in full-height LTO-4 drives, with half-height drives capable of transfers of up to 80 MB/sec compressed data transfer rates may be roughly double those for raw data. LTO-5 and LTO-6 have been proposed, and will offer capacities that roughly double those of the prior versions. Sponsored By: Page 5 of 16

6 A handful of vendors offer LTO libraries, and they include: Hewlett-Packard (HP) Co.'s StorageWorks, IBM Corp., Quantum Corp., Spectra Logic Corp., Sun Microsystems Inc.'s StorageTek, Tandberg Data and others. Small libraries can house as few as one drive, with capacity for two or more drives that can be purchased along with the library or added later. Libraries typically start in a 2-U form factor, and these smaller form factors are probably best suited for SMBs, which may not have the need, or budget, for the larger units. In November 2009, a new DAT drive was announced, the DAT 320, which provides up to 320 GB of compressed storage capacity (160 native). Unlike the earlier DAT cartridges, which used 4mm tape, the cartridges used by DAT 320 use 8mm tape. The DAT 320 also has a transfer rate of 11.9 MBps. Earlier versions of DAT, the DAT 72 and DAT 160, offer compressed capacities of 72 GB and 160 GB, respectively. Because the cartridge sizes are different, it is unlikely that library systems designed for the DAT 72 and DAT 160 drives will support the DAT 320 cartridges. Tandberg Data, HP StorageWorks, and other vendors offer DAT libraries supporting 4mm DAT drives and cartridges. Tape storage and backup considerations for SMBs Based on cost, the decision between DAT and LTO may be fairly simple for many SMBs because the DAT products have considerably lower price entry points. However, it may be appropriate to consider earlier generation LTO-2 and LTO-3 systems that may provide comparable or superior performance and capacities in relation to DAT drives. For example, DAT 160 drives, which have a native capacity of 80 GB and a compressed capacity of 160 GB cost about $800. By contrast, an LTO-2 drive, with a native capacity of 200 GB and a compressed capacity of 400 GB costs about $200 to $400 more. The price of the new DAT 320 will probably be higher than an LTO-2 with slightly higher capacity. The estimated cost of a DAT 320 drive is between $850 and $1,300, according to a search of specialty storage websites. Interface choices are also an important consideration. LTO drives are often available with native Fibre Channel interfaces. Serial Attached SCSI (SAS) is also a frequent offering, as is the more standard SCSI. According to sites offering the DAT 320 drives for sale, these Sponsored By: Page 6 of 16

7 drives will initially be available with Serial Attached SCSI (SAS) or USB interfaces. DAT libraries may not offer Fibre Channel or SCSI. The move towards external SATA (e-sata) may make connections to computers easier and less expensive, because many computers are now equipped with e-sata ports, and e-sata adapter cards are available at low prices. When cost is a major consideration for an SMB, an esataii interface card that includes one esataii port, three internal SATA ports and RAID capabilities, can be purchased for less than $100. This controller can provide RAID for three internal SATA drives, and can connect to an external tape drive. Other tape technologies that have been eclipsed by the rise of DAT and LTO include DLT, SuperDLT, Exabyte and VXA (although, a VXA library is still offered by Tandberg Data). For some companies that don't mind risking the move to technologies that may not be as well supported in the future than DAT and LTO, the move to these other, still useful technologies may save you money. Moving to Fibre Channel may seem like a good idea for some SMBs. But keep in mind that Fibre Channel adapters can cost many hundreds of dollars. They are available in versions that support optical connections (using fiber optic cables and special adapters), and in copper FC adapters that provide lower performance but use copper wire instead of optical cables. The fiber optic cables can connect devices over many miles distance, while the copper cables support much less distance. High-end Fibre Channel can transfer up to 4 GBps. However, tape drives aren't able to read or write at these speeds, so moving to Fibre Channel is probably overkill and a waste of resources. As for SAS and SCSI? This also isn't the cheapest route to go. Their controller cards frequently include RAID capabilities for internal or external drives. These also typically cost at least $200 or more. For many SMBs, once a full backup is made, incremental backups only of changes to data will usually not take up nearly as much time. (For example, if you back up 3 TB of data, but only make a few hundred megabytes of changes each day, the incremental backup should take minutes to perform, rather than hours). For incremental backups of an SMB's drives, a Sponsored By: Page 7 of 16

8 high-speed interface like Fibre Channel is probably unnecessary. For your needs, a USB or esata should be more than adequate. In the end, when an SMB is choosing between the various tape library options, they must ask themselves several questions. How much data will actually be stored on tape, and how frequently will this data be written to tape? How important is form factor -- is there enough room in the physical location to support the library? What will the cost of the tape drives, libraries and media be over a few years of use? Does an upgrade path matter? How long a time window will there be for data transfers, and will the tape drives support it? What interfaces are supported and, if you don't have systems that use the interface, how much will it cost to upgrade your systems? What data backup or data archiving software is provided by the manufacturer? How much will support cost, if needed? And, finally, is tape really the best option to meet my SMB's needs? About this author: Mark Brownstein is a technology journalist with experience editing computer storage publications. He also runs his own networks, is owner and operator of a test lab, has written books about computing topics, and is an MCSA. Sponsored By: Page 8 of 16

9 Linear Tape File System (LTFS) products seen as archiving boon By Sonia R. Lelii, Senior News Writer It's been barely a year since IBM Corp. launched Linear Tape File System (LTFS) for LTO-5 tapes, and vendors are starting to roll out products that support the LTFS open-standard format to make it easier to write and read archived data. IBM, in May, added LTFS support to its tape libraries; Oracle supports LTO-5 on its StorageTek tape libraries and drives; and Hewlett-Packard (HP) Co. said it is working on LTFS support for tape automation in libraries. LTFS support is also showing up in products besides tape libraries. Crossroads Systems Inc. expects to ship StrongBox billed as network-attached storage (NAS) for tape with LTFS support later this year. Quantum Corp. said the ability to import and export to LTFS tapes is on the roadmap for its StorNext software, probably in the first half of In addition, Cache-A supports LTFS across its archive appliances for media and entertainment companies. IBM and HP are the developers of LTFS. IBM supports Linux, Windows and Mac OS, while HP only offers Linux support today and is working on Windows support. LTFS can simplify data archiving Vendors and analysts expect LTFS to eventually play a significant role in the way data is archived to and retrieved from tape. In both cases, it can remove the need for software applications to do some of those functions. Unlike previous versions of LTO, LTO-5 supports media partitioning. This lets the drive write two variable-length partitions on each tape. One partition contains a self-contained hierarchical file system index and a second partition holds the content. The tape contents represented by the file system index are available when a tape is loaded into the drive, and can be viewed by a browser or any application that has the tape attached to it. Sponsored By: Page 9 of 16

10 This is the first tape solution other than a USB [tape] drive that allows you to write data and remove the media and load it to a completely different system and read the files, Crossroads CEO Robert C. Sims said. Any server can read and write files to tape. That has never happened before. So now you can open your Windows Explorer, drag and drop files in the tape where before it was disk-based or a memory solution. Ultimately, LTFS is trying to do file I/O to tape, Evaluator Group senior strategist Randy Kerns said. LTFS has opened a new opportunity for archiving tape usage. Now with LTFS, I can write individual files sequentially on tape but I have an index so I can read the index and position the tape and read that file. The file system partition is organized across the length of the tape and reserves about 5% of the capacity for the file system index. When a tape with a file system index is inserted, the LTFS will present the file information representing the active files on tape. All standalone LTO-5 tape and drive configurations support LTFS without the requirement for backup or data archiving software. In a standalone configuration where the single tape and drive is connected to a client station, end users can retrieve data directly from tape by going into the directory on their client station. Matt Starr, CTO of tape vendor Spectra Logic, said archiving software usually separates the metadata from the content, which means the data is in a purposely formatted scenario and only the software that wrote the data knows the data. With LTFS, all the metadata needed to understand the data is stored on the tape, which makes that tape a self-describing, self-identifying entity, Starr said. It is the equivalent of plugging a USB key into the computer. Kerns said before LTFS, archiving software would invoke the data backup software to write the data to tape. With LTFS, the archiving software can write directly to LTFS tape because it is more like a disk so the inventory structure is more disk-oriented. Data is stored in a file structure so the users can access the data. Now you can write through a file rather than using a backup application, said Kerns. Sponsored By: Page 10 of 16

11 Also, archiving software is not necessarily needed to retrieve the data on the tape, said Kerns. For instance, if the archiving software can write natively to tape as a file then there is no need for archiving software to retrieve the data. But if the archiving software encapsulates the data, then archiving software would be needed to retrieve the data. In another scenario, if the user has a large amount of small files, the archiving software can take those and package them into large files and write them to tape. In this case, archiving software would be needed to retrieve the data. In the case of large files, the user can manually copy the files to tape or use archiving software; therefore, you can either retrieve the data manually or through the use of archiving software. It s not cut and dry, said Kerns. There are a lot of ways this can work. Vendors are beginning to find ways to take advantage of the characteristics of LTFS. For instance, IBM s LTFS Library Edition provides the ability to create a single file system mount point for a logical library managed by a single instance of LTFS running on a single computer system. The Library Edition software resides on a server connected to a library and stores the cartridge index on the server cache. With the IBM Library Edition, you install it on a server and once that is done, I can tell the library to inventory all cartridges and store the cartridges index on the server cache, said IBM senior program manager Bruce Masters. So then I just search the server cache without remounting the cartridge. Each cartridge is self-describing and tells you what is on it. Crossroads claims no archiving software is needed for its StrongBox disk and tape archiving device. StrongBox will mount on the network as a file share to hosts and servers, and has a disk-based cache that moves data to the tape library. StrongBox is generally a NAS device that is expandable, Sims said. It does not require any software or agents to run on an application server. StrongBox connects to the library and gives a persistent view as CIFS or a NFS file system. Sponsored By: Page 11 of 16

12 How will LTFS affect utilization? The biggest potential drawback of LTFS is that it can negatively affect capacity utilization by using up space for changed files that cannot be reclaimed. Tape still is a sequential write media and the LTFS partition is layered on this technology. That means if a user updates a file, the changed file will also be appended with the previous version in place. That space can t be used again. It s a drawback, Kerns said. So if you update a lot of files, the capacity utilization could be small because of the wasted space. IBM s and other vendors response to this is that you can reclaim capacity by copying the data to another tape. Sponsored By: Page 12 of 16

13 Offsite backup tape storage and choosing a tape vaulting service By Brien Posey What you will learn in this tip: Organizations that back data up to tape typically rely on a tape vaulting service to carry backup tapes offsite. That way, if the data center is destroyed by a disaster such as a fire or a tornado, the backups won't be destroyed along with the data center. Given the critical nature of offsite backup tape storage, it's important to perform due diligence in selecting a tape vaulting service. This tip discusses criteria for choosing an offsite tape storage service. What does an offsite backup tape storage service cost? One of the first considerations most organizations take into account when shopping for an offsite backup tape storage service is the cost of the service. As you examine the cost of offsite backup tape storage, it's important to keep in mind that tape vaulting services are notorious for having a lot of hidden charges. For example, some tape vaulting services use different tiers of pricing depending on whether the tape is placed on a rack or if it remains in a shipping container. Some tape vaulting services may also add a fuel surcharge to customer s bills because of high gas prices. Of course the only way that a tape vaulting service can hit you with a fuel surcharge is if they have included a provision for such a charge in the service contract. That's just one of many reasons why it is important to read the fine print. The most common variable in the cost of offsite backup tape storage is pickup and delivery. Generally speaking, the more frequently the tape vaulting service visits your facility to pick up or drop off tapes the more the service will cost you. Most tape vaulting services also charge a premium if you need a tape retrieved on short notice, such as might be the case after a disaster. Sponsored By: Page 13 of 16

14 Disaster protection Since the entire reason for storing tapes offsite is to protect the tapes from disaster, it only makes sense to choose a tape vaulting service that has taken steps to prevent disasterrelated data loss. Ideally, the tape vaulting service that you choose should have vaults that are equipped with ferromagnetic shielding. This shielding protects tapes against magnetism and other forms of electromagnetic radiation that might otherwise erase or corrupt tapes. Adequate fire protection is also critical for any facility that is used to store tapes. Any offsite backup tape service that you interview will tell you that they have good fire protection in place. However, some facilities offer better fire protection than others. When it comes to fire protection, you should insist that the storage facility be NFPA 232 certified. A facility that is NFPA 232 certified complies with all of the codes set forth by the National Fire Protection Association for the protection of records. You can learn more about NFPA 232 certification requirements by visiting the NFPA Web site. Physical security Just as a tape vaulting service needs to provide a facility that is resistant to natural disasters, the storage facility also needs to have good physical security. If you really stop and think about it, most organizations go to great lengths to keep data from walking out the door. For example, organizations might use access control mechanisms that prevent users from copying data to USB storage devices. When you use a tape vaulting service, you are actually sending data out the door. That being the case, you need to be able to trust the service provider to store your data in a secure facility so that your backup tapes are not compromised. On a side note, if you do use a tape vaulting service then you should make sure that all of your backup tapes are encrypted. Remember, there is nothing stopping a rogue employee of the offsite backup tape service from setting up their own server and restoring your backup tapes in an effort to steal your data. Sponsored By: Page 14 of 16

15 The importance of service-level agreements Any reputable tape vaulting service should provide you with a service-level agreement (SLA) that stipulates the terms of the service that you will receive. Specifically, the SLA sets terms regarding how quickly tapes will be delivered in the event of a disaster. As important as the terms of the SLA are, it is equally important to ensure that the SLA is negotiable. After all, your tape vaulting service should meet your needs rather than requiring you to change your disaster recovery procedures so that you can adhere to the tape vaulting service s schedule. In any case, you need to ensure that the SLA states that tapes can be delivered to you 24 hours a day, seven days a week. This is critically important since disasters have a way of happening late at night or on the weekends. Tracking and compliance Finally, the tape vaulting service that you choose should be able to provide you with a full audit trail of the tapes they pick up and deliver. You should also expect to be able to access a Web-based tape inventory system that allows you to see which tapes the service provider has and to track any tapes that might be missing. As you can see, there are a number of different things that you should look for when choosing an offsite backup tape service. To get the best service, it's important to do a little upfront work to save you time and money in the long run Sponsored By: Page 15 of 16

16 Resources from Iron Mountain Compliant Media Management: Best Practices Guide Guide to Improving Your Tape Storage Practices Offsite Tape Vaulting Brochure: Secure Media Management About Iron Mountain Iron Mountain Incorporated (NYSE: IRM) provides information management solutions that help organizations lower the costs, risks and inefficiencies of managing their data. The company s solutions enable customers to protect and better use their information regardless of its format, location or life-cycle stage so they can optimize their business and ensure proper recovery, compliance and discovery. Founded in 1951, Iron Mountain manages billions of information assets, including business records, electronic files, medical data, s and more for organizations around the world. Visit or follow us on Twitter ( for more information. Sponsored By: Page 16 of 16