In-Depth

ATA-Class Storage -- The End of Tape Backups?

DRBC #4: With a solid DRBC plan in place, it might be time to consider replacing your backup plan with more reliable technology that doesn't call for the janitor at a remote site to occasionally change tapes.

• By Bill Heldman
• 06/27/2006

The same is true of enterprise-class tape backup systems -- only on a vastly larger scale.In the old days of DRBC we used tape backup devices and racks upon racks of backup tapes in order to protect our enterprise. In one (fairly current) job I was in, the operations department still used five 25-year-old Storage Tek tape backup units. On a monthly basis they would routinely rotate 5500 tapes. All this for a little over a gigabyte of mainframe storage! One tape would be used for a little 1MB file, another for a few hundred kilobytes and so on.

Job security, yes. Practicality, absolutely not.

Think of all of the little one-off 4mm, 8mm, DAT and LDAT tape systems that shipped with the servers you or someone before you ordered. Administrators everywhere are still chasing after those tapes! And, people are still buying robotic tape changing machines to routinely replace the LDAT tapes in the backup system -- expensive tapes they've procured over the years.

Here's the million dollar DRBC question: Are your tapes routinely going offsite, using some sort of rotation system? Answer: Doubtful. The sad truth is that the majority of organizations have elaborate tape back-up systems but do nothing with the tapes once they've recorded backups onto them. There is no routine "ship them offsite" mechanism. It is quite likely that the tapes sit on shelves or in tape containers in a back room and are not thought of again until the next time they're needed. Is this good DRBC practice? Of course you know the answer to that. Absolutely not!

"But", you say, "I can't give up the incredibly expensive investment I have in my tape back-up units. And what about the back-up software I use? That software cost us an arm and a leg! You've gone too far. You're talking a major capital investment in software and hardware, not to mention an Operations and Maintenance investment in professional services to get it installed and operational."

True. You do have a capital investment in your tape back-up gear. But, realistically speaking, how long has it been in service? If the answer is two years or more, odds are you are close to the end of the depreciation cycle for that equipment and it's time to venture into greener pastures. You should begin to think of purchasing ATA-class disk array equipment to replace your backup units. We'll talk more about these devices later on.

The software you'll likely be able to keep, as it will probably be able to converse with today's ATA disk array equipment. And if not, there is software available that will make it easy for you to transport data from your servers to the disk array without using tape backup software. But for the time being keep "I'll probably be able to leverage my old tape back-up software across the new ATA-class disk arrays" in the back of your mind for later.

The bottom line is that the new breed of ATA-class storage arrays are relatively inexpensive, they have awesome companion software available for them, they are manufactured by world-class manufacturers, and they provide you with a safe way to produce backups and restorations much more quickly and reliably than before. Plus, they juxtapose nicely with DRBC plans.

You want ATA-class back-up operations because the speed with which you can do your backups is no longer limited by the groggy speed of the tapes. Now your primary bottleneck will be your network bandwidth, and we all know that today's networks are usually quite robust.

Used to be that performing a backup was an overnight thing. Now you can plan your backups to fit your daytime schedule. Restores were a problem because they required navigating the software until you found the volume you wanted, then actually finding the tape or tapes that you needed in order to retrieve the data. This slow, painful operation is now quick and much easier than before.

The Gear
Let's talk about some of the manufacturers -- folks you may have already dealt with. You may even possess some of their equipment. Please note that I've just listed three of my favorite players. There are many others to choose from.

Network Appliance -- This company has an amazing lineup of SAN and NAS gear for almost any undertaking. This company's products work well, and the company stands behind them.

The NearStore Virtual Tape Library (VTL) is a disk-to-disk SATA-based backup appliance that appears as a tape library to your backup software. Available in capacities from 4.5 Terabytes (TB) to 168TB, there is plenty of room for you to back up old data and get it off of your servers. The VTL is visible by today's enterprise-class backup products such as Legato, Symantec, HP, et al.

If you've been hankering to get rid of your clunky old tape backup software program, you can combine the VTL with NetApp's SnapVault software. This combination immediately pops you into a modern disk-based backup paradigm that allows you to reach out and quickly back up anything on the net.

NetApp also has other enterprise-class SAN and NAS arrays that can be utilized in conjunction with the NearStore. Architecturally, you can probably envision SAN arrays sitting at your organization's main points of operation, fanning out offsite to one or more NearStores that pull in data from the enterprise and store it out of harm's way, all over a fast wire. No more hauling tapes around (which few of us did anyway), or worrying about Father, Son, Grandfather or Towers of Hanoi backup strategies.

LeftHand Networks -- LeftHand is in the business of iSCSI SANs. Because they're iSCSI, you don't have to mess around with complicated Fibre Channel connections, and the equipment is thus less expensive to operate. Talk to the big players like EMC and you might hear stories about iSCSI not being standardized across vendors -- scary interoperability stories. That's because the big players have a huge investment in FC arrays. But the truth is, iSCSI works as a standard and LeftHand has been shipping gear for a long time now.

LeftHand has some software called "SAN iQ/Snap". The key word here is "snap", meaning, more or less, a snapshot of the data that you want to back up. The idea is straightforward: You designate the files that you want to snap and allow iQ/Snap to do its work. Note that these files are on the SAN, not necessarily on a local server. Once the snap has been taken, it's an easy thing to move it to another device out of harm's way. Note that iQ/Snap will work with some implementations of Windows-based backup software.

Snaps typically require a dedicated piece of space on the SAN in which to hold the snap. Not so in LeftHand's case, which can place the snapshot copy elsewhere.

LeftHand is a Microsoft Certified Partner, and this shows up in their products. Note that alongside iQ/Snap, LeftHand has an implementation of Microsoft's Volume Shadow Copy Service (VSS), allowing your server VSS implementations to initiate and manage snaps from the LeftHand SAN, ostensibly for movement elsewhere. Additionally, LeftHand has leveraged Microsoft's Multipath I/O (MPIO) framework to optimize the ability of a Windows Server 2003 server to work with SAN data. LeftHand's SAN iQ/Remote Copy software allows you to pick up data from remote locations, copying it to the SAN for safekeeping. This would be tremendously useful in those locations where you had no administrator and wanted to be sure you were adequately and accurately backing up the site.

It seems to me that the LeftHand implementations are proprietary, single-stop-shopping environments. This might mean extra effort in getting a LeftHand device to "play nicely in the sandbox" with another device on the network. Be that as it may, the upsides are the cost-effectiveness of the software and hardware -- all wrapped up in an iSCSI framework.

EMC -- One of my favorite companies is EMC. I take a ribbing from a lot of people; I suppose because EMC is like Microsoft, one of those companies everyone loves to hate. But my experience has been that all EMC people I've been in contact with -- salespersons, technical reps, installers and service personnel -- have been top-grade. I like the products, and I like the way I'm treated when I'm an EMC customer.

EMC's ATA-class box is called the Clariion. The flagship backup and restoration appliance is currently the Clariion disk library series. Using a device in this series allows you guaranteed interoperability with other elements of your network that need backed up, and provides you with a path from Small to Medium Business (SMB), all the way up to large-scale enterprises.

EMC's software for backups is called EMC Networker. There is a Networker module for most enterprise ERP, database and email implementations.

EMC has an Insignia line of software and hardware designed for SMBs.

So How Do I Start?
Clearly, these are just three examples in a universe of vendors who are in the backup-to-disk market. The technology is tried and proven. It works, and it gives time back to administrators -- most of whom typically spend their days as though their hair is on fire. It is time to consider, architect, plan and implement a backup-to-disk scenario for your DRBC plan.

So how do you start? Well, I think the best place is at the top, with the CIO. You need to understand four basic things in order to prepare a document that's going to get you what you want:

Outline the need with statistics -- Most administrators try to sell their managers on products by simply insisting that this is what they absolutely must have to continue operation. Folks, let me be frank. Your CIO didn't just fall off of a load of pumpkins. She knows that up till now, you've gotten along just fine without all the latest and greatest software and hardware. And, she has a variety of hands out, all begging for funds.

What you need to do is document the time and money that is wasted using current methodologies. You can show how things have gotten busier over time -- where once the situation might've been OK, now it is a nightmare. You must illustrate to your CIO how the situation has gotten out of hand so that she clearly understands the problem you face.

Understand and talk about capitalization -- Once you've prepared a sound problem statement -- one that is going to get noticed and get some airplay -- the next thing to do is to make sure that you understand how big equipment is capitalized. You must understand financing, depreciation, the projected length of operation of the new equipment, the project plan needed to implement the system, and any additional costs that are needed to install it.

You want to be able to illustrate to your CIO why it's OK to bag those old tape back-up devices, and how you propose financing the new backup-to-disk arrays and software. You want to tell her how long you anticipate keeping the devices, because this denotes the depreciation value of the equipment. Also, it would be wise to point out anticipated Mean Time Between Failures (MTBF), as this illustrates any expected downtime you might encounter.

By simply talking in capitalization terms, your CIO grasps that you basically understand what she is up against when it comes to budget planning and spending.

Understand and talk about O&M -- Big-league gear like this doesn't come as a standalone box. There are ongoing maintenance costs you have to pay for things like 24x7x365 monitoring, as well as software upgrades. You should be able to talk about the operations costs -- those people in your shop that will actively monitor and maintain the equipment, so that she understands what today's gear looks like as contrasted with what you're proposing. It could be that full-time employees (FTE) that are currently working backup operations could be redeployed elsewhere, thanks to the deployment of the new solution.

By putting things into a dollars and cents mentality, it will help you rationalize the expenditure you're proposing. She will realize that you are trying to think like she thinks, and not just demanding that you must have the latest and greatest thing.

Risk assessment -- You also want to provide a full risk assessment. You start by outlining the risks that the organization faces today, given the current situation. Then you move into how the new implementation will reduce those risks. You should also talk about the risks you expect to encounter with the new proposed solution. Don't be a "pie-in-the-sky-guy". There will be risks that arise with the new system. You should spend some time thinking about what they are and documenting a mitigation strategy.

Note how this new solution fits into your over all DRBC architecture -- By this time, you've doubtless been dialoging with your CIO regarding DRBC. Your segue moment comes when you can show how the current tape backup paradigm really isn't DRBC -- if anything it's a loose fit disguised as DRBC. And you can point out how the new system will map very nicely into your DRBC architecture because one or more of the disk arrays will live elsewhere, away from headquarters.

When you're done preparing your presentation, schedule an appointment, meet with your CIO and other dignitaries and make your case. You start with why the current situation is no longer palpable, given the current infrastructure. Next you go into the research that you did with regard to the latest solutions -- including a discussion of acceptable industry standards. Finally, you introduce your proposal, including your risk assessment and end with the proposed cost of the new solution, along with financing plans, and DRBC architecture fit.

Then you ask for the dough.

Let's Rewind
The point to this is that if you have not already replaced your current tape backup system, why not? There is literally no need for such gear in the enterprise any longer. Disks are fast and reliable, tapes are not. You can take snapshots all day long, and when you are finally ready to get rid of very old data, you can simply burn it to DVD for safe, long-term storage.