NEW YORK CITY -- Cloud storage received a great deal of attention during Storage Decisions this week, with experts...
laying out the pros and cons of public and private storage clouds and attendees voicing concerns over price and security.
The cloud was the subject of several sessions during the two-day conference featuring independent expert content for senior-level IT decision makers. Experts often introduced their sessions by offering a definition for a private storage cloud.
“What is [private] cloud storage?” asked Howard Marks, chief scientist at DeepStorage.Net, during his presentation on building your own private cloud or hybrid storage cloud. “Now it’s anything the guy who has a product wants it to be.”
He said private cloud storage should be “what public cloud products are” -- multi-tenant, infinitely elastic, with an object interface, Internet accessibility and low cost.
During his session titled “The Truth about Cloud Storage,” Marc Staimer, founder of Dragon Slayer Consulting, characterized the private cloud as “using your own IT or a collocation site to lower costs.” He added that cloud storage can be allocated on-demand or pay-as-you-go, and is application independent.
There was even a disagreement over whether private clouds even exist yet.
“How many of you have built a private cloud yet?” asked Arun Taneja, founder and consulting analyst at Taneja Group during his presentation, “Integrating On-Site Storage with Cloud Services.”
A few hands went up.
“I’m surprised, because I don’t think a private cloud is there yet,” Taneja replied. He said cloud storage’s definition included the ability to rapidly and easily configure and provision resources to meet each user’s needs. “We might be close, but we still don’t have all the pieces to build a private cloud.”
Others disagreed, although no one disputed that public storage clouds are far more common than private clouds.
DeepStorage.Net's Marks provided a list of products vendors pitch for building a private cloud during his talk, but admitted he didn’t consider all of them true cloud products. For instance, he listed scale-out NAS systems with the caveat, “I wouldn’t call it cloud, but the vendors do.”
Dragon Slayer Consulting's Staimer said he knows of some large private cloud implementations, but said the term isn't as easy to nail down as it is for other technologies.
“Not all cloud storage is the same,” he said. “Remember, the cloud is just somebody else’s data center.”
Cloud storage advantages
The experts said advantages of the cloud include a compelling economic case that turns a fixed-cost investment into a pay-as-you-go model. Other positives include the ability to easily increase and decrease capacity, accessibility any time and from anywhere, fast deployment, nearly infinite scalability, and the removal of traditional tech refreshes and data migrations.
“With a cloud, your capex is gone unless you buy a [cloud storage] gateway,” Taneja said.
Another advantage of the cloud, said the experts, is that it can eliminate data migration projects and unscheduled downtime.
“The best part about cloud storage is you don’t have to migrate it,” DeepStorage.Net's Marks said. “You don’t have to worry about power or how much space you have. The cloud isn't built for low latency, it’s for archive data, huge stuff that doesn't change but takes up a lot of space.”
Cloud storage disadvantages
When Taneja Group's Taneja asked for questions from the audience after his cloud session, the first few were about security and price. He said these were common concerns he hears from storage admins, especially worries over security.
“All the analysis we’ve done, the answer is yes, it’s secure.” he said. “I’m not worried about security, we haven’t heard of any data breaches in the cloud. The hard part is convincing management.”
However, there are legitimate disadvantages. They include an inability to run most legacy applications and the lack of complete control over data in public clouds. Plus, the cloud isn't suited for tier 1 data or business critical applications.
Lack of control over data has also been an issue with public clouds. Taneja pointed out that cloud providers’ service-level agreements (SLAs) are inadequate to cover the risk of data that is temporarily unavailable. “What good is it to get $59 back at the end of the month when your job is gone?” he said.
DeepStorage.Net's Marks echoed that sentiment. “If Amazon makes a mistake, you lose your job,” he said, adding that another issue is moving data from one provider to another if you switch. “How do I get my data back if I don’t like my provider anymore?”
Cloud storage advice
The experts agreed that the cloud isn't well suited for primary storage.
Instead, Dragon Slayer Consulting's Staimer said the cloud is “good for archiving data, secondary data, tertiary data, data that you don’t need daily.”
The experts also agreed that object storage is almost mandatory for cloud storage, because it is location independent, and its use of metadata gives it built-in retention and data protection policies. That gives it advantages over block and file storage for the cloud.
“It gives you more control over data in the cloud than you have in your own data center,” Staimer said of object storage. “Unless you’re really comfortable with your SAN, I would never recommend it as a cloud-based architecture.”
Taneja Group's Taneja agreed. “I wouldn’t do tier 1 storage in the cloud right now,” he said.
Instead, DeepStorage.Net's Marks said the cloud is best used for archived data that requires fast access times.
“If your acceptable latency is hours, you want to go back and look at tape,” he said. “The cloud is for something that will be accessed relatively quickly.”
Taneja Group's Taneja said if storage administrators don’t look to embrace the cloud, their internal customers will. “And they’ll do it willy-nilly, they’ll sign up with Amazon on their credit cards,” he said. “You don’t want your customers doing this willy-nilly.”
“Because there are so many vendors, you could get a good price now,” Dragon Slayer Consulting's Staimer said. “It should be part of your storage discussion.”