Posts Tagged ‘Linear Tape File System (LTFS)’

Industrial Strength SDS for the Cloud

June 12, 2014

The hottest thing in storage today is software defined storage (SDS). Every storage vendor is jumping on the SDS bandwagon.

The presentation titled Industrial -Strength SDS for the Cloud, by Sven Oehme, IBM Senior Research Scientist, drew a packed audience at Edge 2014 and touched on many of the sexiest acronyms in IBM’s storage portfolio.  These included not just GPFS but also GSS (also called GPFS Storage Server), GNR, LROC (local read-only cache), and even worked in Linear Tape File System (LTFS).

The session promised to outline the customer problems SDS solves and show how to deploy it in large scale OpenStack environments with IBM GPFS.  Industrial strength generally refers to large-scale, highly secure and available multi-platform environments.

The session abstract explained that the session would show how GPFS enables resilient, robust, reliable, storage deployed on low-cost industry standard hardware delivering limitless scalability, high performance, and automatic policy-based storage tiering from flash to disk to tape, further lowering costs. It also promised to provide examples of how GPFS provides a single, unified, scale-out data plane for cloud developers across multiple data centers worldwide. GPFS unifies OpenStack VM images, block devices, objects, and files with support for Nova, Cinder, Swift and Glance (OpenStack components), along with POSIX interfaces for integrating legacy applications. C’mon, if you have even a bit of IT geekiness, doesn’t that sound tantalizing?

One disclaimer before jumping into some of the details; despite having written white papers on SDS and cloud your blogger can only hope to approximate the rich context provided at the session.

Let’s start with the simple stuff; the expectations and requirements for cloud  storage:

  • Elasticity, within and across sites
  • Secure isolation between tenants
  • Non-disruptive operations
  • No degradation by failing parts as components fail at scale
  • Different tiers for different workloads
  • Converged platform to handle boot volumes as well as file/object workload
  • Locality awareness and acceleration for exceptional performance
  • Multiple forms of data protection

Of course, affordable hardware and maintenance is expected as is quota/usage and workload accounting.

Things start getting serious with IBM’s General Parallel File System (GPFS). This what IBMers really mean when they refer to Elastic Storage, a single name space provided across individual storage resources, platforms, and operating systems. Add in different classes of storage devices (fast or slow disk, SSD, Flash, even LTFS tape), storage pools, and policies to control data placement and you’ve got the ability to do storage tiering.  You can even geographically distribute the data through IBM’s Active Cloud Engine, initially a SONAS capability sometimes referred to as Active File Manager. Now you have a situation where users can access data by the same name regardless of where it is located. And since the system keeps distributed copies of the latest data it can handle a temporary loss of connectivity between sites.

To protect the data add in declustered software RAID, aka GNR or even GSS (GPFS Storage Server). The beauty of this is it reduces the space overhead of replication through declustered parity (80% vs. 33% utilization) while delivering extremely fast rebuild.  In the process you can remove hardware storage controllers from the picture by doing the migration and RAID management in software on your commodity servers.

dino industrial sds 1

In the above graphic, focus on everything below the elongated blue triangle. Since it is being done in software, you can add an Object API for object storage. Throw in encryption software. Want Hadoop? Add that too. The power of SDS.  Sweet

The architecture Oehme lays out utilizes generic servers with direct-attached switched JBOD (SBOD). It also makes ample use of LROC, which provides a large read cache that benefits many workloads, including SPECsfs, VMware, OpenStack, other virtualization, and database workloads.

A key element in Oehme’s SDS for the cloud is OpenStack. From a storage standpoint OpenStack Cinder, which provides access to block storage as if it were local, enables the efficient sharing of data between services. Cinder supports advanced features, such as snapshots, cloning, and backup. On the back end, Cinder supports Linux servers with iSCSI and LVM; storage controllers; shared filesystems like GPFS, NFS, GlusterFS; and more.

Since Oehme’s  is to produceindustrial-strength SDS for the Cloud it needs to protect data. Data protection is delivered through backups, snapshots, cloning, replication, file level encryption, and declustered RAID, which spans all disks in the declustered array and results in faster RAID rebuild (because there are more disks available for RAID rebuild.)

The result is highly virtualized, industrial strength SDS for deployment in the cloud. Can you bear one more small image that promises to put this all together? Will try to leave it as big as can fit. Notice it includes a lot of OpenStack components connecting storage elements. Here it is.

dino industrial sds 2

DancingDinosaur is Alan Radding. Follow DancingDinosaur on Twitter @mainframeblog

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IBM Edge2014: It’s All About the Storage

May 22, 2014

When your blogger as a newbie programmer published his first desktop application in the pre-historic desktop computing era it had to be distributed on consumer tape cassette. When buyers complained that it didn’t work the problem was quickly traced to imprecise and inconsistent consumer cassette storage. Since the dawn of the computer era, it has always been about storage.

It still is. Almost every session at IBM Edge2014 seemed to touch on storage in one way or another.  Kicking it all off was Tom Rosamilia, Senior Vice President,  IBM Systems & Technology Group, who elaborated on IBM’s main theme not just for Edge2014 but for IBM at large: Infrastructure Matters Because Business Outcomes Matter. And by infrastructure IBM mainly is referring to storage. Almost every session, whether on cloud or analytics or mobile, touched on storage in one way or another.

To reinforce his infrastructure matters point Rosamilia cited a recent IBM study showing that 70% of top executives now recognize infrastructure as an enabler. However, just 10% reported their infrastructure was ready for the challenge.  As an interesting aside, the study found 91% of the respondents’ customer facing applications were using the System z, which only emphasizes another theme at IBM Edge2014—that companies need to connect systems of record with systems of engagement if they want to be successful.

In fact, IBM wants to speed up computing overall, starting with flash and storage. A study by the Aberdeen Group found that a 1 sec. delay in page load resulted in a 77% loss in conversions, 11% fewer page views, and a 16% decrease in customer satisfaction.  IBM’s conclusion: In dollar terms, this means that if your site typically earns $100,000 a day, this year you could lose $2.5 million in sales.  Expect all IBM storage to be enabled for some form of flash going forward.

First announced at IBM Edge2014 were the FlashSystem 840 and the IBM FlashSystem V840, which includes integrated data virtualization through IBM’s SVC and its various components. It also boasts a more powerful controller capable of rich capabilities like compression, replication, tiering, thin provisioning, and more. Check out the details here.

Also at Edge2014 there was considerable talk about Elastic Storage. This is the storage you have always imagined. You can manage mixed storage pools of any device. Integrate with any OS. Write policies to it. It seems infinitely scalable. Acts as a universal cloud gateway. And even works with tape.

Sounds magical doesn’t it?  According to IBM, Elastic Storage provides automated tiering to move data from different storage media types. Infrequently accessed files can be migrated to tape and automatically recalled back to disk when required—sounds like EasyTier built in. Unlike traditional storage, it allows you to smoothly grow or shrink your storage infrastructure without application disruption or outages. And it can run on a cluster of x86 and POWER-based servers and can be used with internal disk, commodity storage, or advanced storage systems from IBM or other vendors. Half the speakers at the conference glowed about Elastic Storage.  Obviously it exists, but it is not an actually named product yet. Watch for it, but it is going to have a different name when finally released, probably later this year. No hint at what that name will be.

IBM, at the conference, identified the enhanced XIV as the ideal cloud infrastructure. XIV eliminates complexity. It enables high levels of resiliency and ensures service levels. As one speaker said: “It populates LUNs and spreads the workload evenly. You don’t even have to load balance it.” Basically, it is grid storage that is ideal for the cloud.

LTFS (Linear Tape File System) was another storage technology that came up surprisingly frequently. Don’t assume that that tape has no future, not judging from IBM Edge2014. LTFS provides a GUI that enables you to automatically move infrequently accessed data from disk to tape without the need for proprietary tape applications. Implementing LTFS Enterprise Edition allows you to replace disk with tape for tiered storage and lower your storage TCO by over 50%. Jon Toigo, a leading storage analyst, has some good numbers on tape economics that may surprise you.

Another sometimes overlooked technology is EasyTier, IBM’s storage tiering tool.  EasyTier has evolved into a main way for IBM storage users to capitalize on the benefits of Flash. EasyTier already has emerged as an effective tool for both the DS8000 and the Storwize V7000.  With EasyTier small amounts of Flash can deliver big performance improvements.

In the coming weeks DancingDinosaur will look at other IBM Edge 2014 topics.  It also is time to start thinking about IBM Enterprise 2014, which combines the System z and Power platforms. It will be at the Venetian in Las Vegas, Oct 6-10. IBM Enterprise 2014 is being billed as the premier enterprise infrastructure event.

BTW, we never effectively solved the challenge of distributing desktop programs until the industry came out with 5.5” floppy disks. Years later my children used the unsold floppies as little Frisbees.

Follow Alan Radding and DancingDinosaur on Twitter, @mainframeblog

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