Winning the mid-tier war
Winning the mid-tier war
With hard disk storage vendors muscling into the non-mission critical storage market, could tape storage be relegated to disaster recovery only? Stuart Finlayson investigates.
Not so long ago, it was considered rather extravagant, foolhardy even, to store any data other than the mission critical variety on hard disk. This was primarily down to the fact that hard disk vendors offered one price plan for all data stored, irrespective of its value, meaning that companies were paying top dollar to store archival documents as well as critical data.
Thanks to technological advancement in the hard disk community, the market is gradually being turned on its head. Now hard disk storage vendors are able to offer tiered price plans to suit the type of information that is being stored. This, coupled with the improvement over tape in terms of retrieval speed it offers, is seeing hard disk storage emerge as the logical option to businesses and organisations.
"Definitely one of the issues that is driving [the market] at the moment is tiers of storage," says Harry Christian, marketing manager at Network Appliance. "What we are saying is why do you have to pay the same amount of money - be it on disk, tape or otherwise - for different tiers of data."
"It makes a lot of sense to pay top whack for the top tier of data because it is mission critical and needs to work at lightning speed. For tier two and tier three-type data, you don't necessarily need to be paying the same sort of money. You will suffer from a speed of access stand point but that's alright because you don't need the same sort of access speed when dealing with that type of data." Christian says.
Clive Gold, marketing director at EMC, agrees that the market has taken on a different complexion. "The issue is no longer expensive disk versus tape, as we have high service level systems, medium level and low level, and with each level comes different cost, so we can store mission critical data at a cost of, say, 20 cents per megabyte, all the way down to one or two cents per megabyte, albeit with slower access, so it's about matching the type of data, and how valuable the data is, to how much it costs to keep it."
"We are getting to a stage where [even the] purchase price is comparable to tape. Last year we saw optical being surpassed by disk, so it is now less expensive to buy a hard disk system than it is optical, but the real issue is when you look at how much tape costs to run and the amount of errors that people are finding on tapes after a period of time, it is often more effective to look at keeping information online, " says Gold.
The move by hard disk vendors to offer value across the various tiers of storage has been largely driven by the users, according to Vic Madarevic, marketing and manager of storage solutions in Australia and New Zealand for Hitachi Data Systems.
"Customers are no longer prepared to pay a fixed amount for storage regardless of its use. It is also true that the total cost of ownership [of a hard disk system] is now so competitive that I would almost challenge anyone to do a complete total cost of ownership analysis, which includes everything from manpower resources, cost of space for tape libraries, cost of tape slots, the tape media itself and its manageability," says Madarevic.
Clive Gold, of EMC, agrees, adding that EMC addressed all those issues when developing the Centera. "What we are finding is that we can produce systems to meet different requirements, so for example, in the fixed content area we use the ATA drives in the Centera to keep fixed content online very cost effectively. When you look at the cost of keeping information and getting access to that information, (the purchase price of a system) is becoming a smaller component of that. If you look at the cost of finding information that is stored away in an archive in paper form it is prohibitive these days - it costs a fortune. That is where people are looking at the current price points and think 'I can keep this online instead of archiving it.'"
What about security?
While there can be no argument that disk storage has the edge over tape-based systems in terms of data retrieval speed and accessibility, what about security? What do you want when the unthinkable happens? According to the disk vendors, it depends on the type of loss. They agree that disk systems provide as safe and secure back up environments as tape, but at the same time all acknowledge that in terms of disaster recovery, tape is still very much the system of choice.
"I would never say that people do not need tape whatsoever as tape is needed for disaster recovery and business continuity as a backup, but for quick access to information online such as cheque images and other legal documents, these days, more and more information, no matter how old, needs to be readily available and quickly accessible. So if you factor in all the business needs, disk is becoming a very cheap alternative," says Gold.
Gold adds that as the industry has developed, users view disaster recovery as much more than protection against a total meltdown. "We have been mirroring production data off-site for nine years and we have taken that level of technology and moved it into the mid-range. It is so affordable now to not only have a copy there but actually use that copy. We have moved away from the time where people looked at disaster recovery as being very expensive insurance to where people can have production at both sides. They can be using their copy to do their physical backups, check databases and all sorts of other things so it is no longer a sunk investment and it is affordable to the mid tier. With that functionality, why would anyone want to dump it all on tape."
"The tape vendors would argue that you can take the tape out and leave it somewhere else and that the cost of the physical tape compared to the cost of the disk is a huge disparity and that is absolutely right. That is why tape will probably be around for a long time as that ultimate backup in case of an absolute catastrophe, but for everything else, tape is no longer a valid answer," says Gold.
Another issue that has had to be faced by storage vendors in recent years, particularly in the wake of the high profile collapse of companies such as Enron and, closer to home, HIH, is that of the legislation introduced requiring companies to keep data for set periods of time.
For medium to large organisations, retaining all emails and other documents for months or years before being allowed to dispose of them has created storage problems which disk storage vendors have had to address.
"The legal requirement to keep information for a certain amount of time and the need to be able to access that information has meant that for the last twelve to eighteen months we have been developing software solutions to enable data to be 'read only' so even though it is on disk, there is a legal requirement that it cannot be overwritten or deleted, so we have functionality within the storage to actually protect the data from being overwritten to satisfy the legal requirements," says Vic Madarevic of Hitachi Data Systems.
Similarly, EMC has developed such tools into its Centera architecture, as Clive Gold explained: "With other systems there is a lot of waste and duplication, but Centera takes that out as it only stores the same information once, no matter how many people try to store it or access it.
"We have also built protection into the hardware so that if, for example, information has to live for five years, when it gets stored you tell Centera that it has to live for five years, then no matter who tries to delete that, Centera will not them do that, so we have been able to get it through the SEC committees in the US as a SEC compliant device," says Gold.
So what of the future of tape? EMC's Clive Gold has the last word: "The role of tape has changed dramatically and will continue to change. Right now, the ultimate backup is still tape if both your sites are lost completely and you have to rebuild, or you need a copy of information as it was, say, eight years ago. That's going to be kept on tape somewhere in a vault. Right now, we can't see an alternative to that, but people who are using it for their primary backup, and are using it to move information around and take off information so that they can change the architecture of what they are running on, or put it in a data warehouse or anything like that, very few people are doing that anymore."
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