The rise of RDMA

I have known of RDMA (Remote Direct Memory Access) for quiet some time, but never in depth. But since my contract work ended last week, and I have some time off to do some personal development, I decided to look deeper into RDMA. Why RDMA?

In the past 1 year or so, RDMA has been appearing in my radar very frequently, and rightly so. The speedy development and adoption of NVMe (Non-Volatile Memory Express) have pushed All Flash Arrays into the next level. This pushes the I/O and the throughput performance bottlenecks away from the NVMe storage medium into the legacy world of SCSI.

Most network storage interfaces and protocols like SAS, SATA, iSCSI, Fibre Channel today still carry SCSI loads and would have to translate between NVMe and SCSI. NVMe-to-SCSI bridges have to be present to facilitate the translation.

In the slide below, shared at the Flash Memory Summit, there were numerous red boxes which laid out the SCSI connections and interfaces where SCSI-to-NVMe translation (and vice versa) would be required.

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The engineering of Elastifile

[Preamble: I was a delegate of Storage Field Day 12. My expenses, travel and accommodation were paid for by GestaltIT, the organizer and I was not obligated to blog or promote the technologies presented in this event]

When it comes to large scale storage capacity requirements with distributed cloud and on-premise capability, object storage is all the rage. Amazon Web Services started the object-based S3 storage service more than a decade ago, and the romance with object storage started.

Today, there are hundreds of object-based storage vendors out there, touting features after features of invincibility. But after researching and reading through many design and architecture papers, I found that many object-based storage technology vendors began to sound the same.

At the back of my mind, object storage is not easy when it comes to most applications integration. Yes, there is a new breed of cloud-based applications with RESTful CRUD API operations to access object storage, but most applications still rely on file systems to access storage for capacity, performance and protection.

These CRUD and CRUD-like APIs are the common semantics of interfacing object storage platforms. But many, many real-world applications do not have the object semantics to interface with storage. They are mostly designed to interface and interact with file systems, and secretly, I believe many application developers and users want a file system interface to storage. It does not matter if the storage is on-premise or in the cloud.

Let’s not kid ourselves. We are most natural when we work with files and folders.

Implementing object storage also denies us the ability to optimally utilize Flash and solid state storage on-premise when the compute is in the cloud. Similarly, when the compute is on-premise and the flash-based object storage is in the cloud, you get a mismatch of performance and availability requirements as well. In the end, there has to be a compromise.

Another “feature” of object storage is its poor ability to handle transactional data. Most of the object storage do not allow modification of data once the object has been created. Putting a NAS front (aka a NAS gateway) does not take away the fact that it is still object-based storage at the very core of the infrastructure, regardless if it is on-premise or in the cloud.

Resiliency, latency and scalability are the greatest challenges when we want to build a true globally distributed storage or data services platform. Object storage can be resilient and it can scale, but it has to compromise performance and latency to be so. And managing object storage will not be as natural as to managing a file system with folders and files.

Enter Elastifile.

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Can CDMI emancipate an interoperable medical records cloud ecosystem?

PREFACE: This is just a thought, an idea. I am by no means an expert in this area. I have researched this to inspire a thought process of how we can bring together 2 disparate worlds of medical records and imaging with the emerging cloud services for healthcare.

Healthcare has been moving out of its archaic shell in the past few years, and digital healthcare technology and services are booming. And this movement is part of the digital transformation which could eventually lead to a secure and compliant distribution and collaboration of health data, medical imaging and electronic medical records (EMR).

It is a blessing that today’s medical imaging industry has been consolidated with the DICOM (Digital Imaging and Communications in Medicine) standard. DICOM dictates the how medical imaging information and pictures are used, stored, printed, transmitted and exchanged. It is also a communication protocol which runs over TCP/IP, and links up different service class providers (SCPs) and service class users (SCUs), and the backend systems such as PACS (Picture Archiving & Communications Systems) and RIS (Radiology Information Systems).

Another well accepted standard is HL7 (Health Level 7), a similar Layer 7, application-level communication protocol for transferring and exchanging clinical and administrative data.

The diagram below shows a self-contained ecosystem involving the front-end HIS (Hospital Information Systems), and the integration of healthcare, medical systems and other DICOM modalities.

Hospital Enterprise

(Picture courtesy of Meddiff Technologies)

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Praying to the hypervisor God

I was reading a great article by Frank Denneman about storage intelligence moving up the stack. It was pretty much in line with what I have been observing in the past 18 months or so, about the storage pendulum having swung back to DAS (direct attached storage). To be more precise, the DAS form factor I am referring to are physical server hardware that houses many disk drives.

Like it or not, the hypervisor has become the center of the universe in the IT space. VMware has become the indomitable force in the hypervisor technology, with Microsoft Hyper-V playing catch-up. The seismic shift of these 2 hypervisor technologies are leading storage vendors to place them on to the altar and revering them as deities. The others, with the likes of Xen and KVM, and to lesser extent Solaris Containers aren’t really worth mentioning.

This shift, as the pendulum swings from networked storage back to internal “direct-attached” storage are dictated by 4 main technology factors:

  • The x86 server architecture
  • Software-defined
  • Scale-out architecture
  • Flash-based storage technology

Anyone remember Thumper? Not the Disney character from the Bambi movie!

thumper-bambi-cartoon-character

When the SunFire X4500 (aka Thumper) was first released in (intermission: checking Wiki for the right year) in 2006, I felt that significant wound inflicted in the networked storage industry. Instead of the usual 4-8 hard disk drives in the all the industry servers at the time, the X4500 4U chassis housed 48 hard disk drives. The design and architecture were so astounding to me, I even went and bought a 1U SunFire X4150 for my personal server collection. Such was my adoration for Sun’s technology at the time.

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SMB Witness Protection Program

No, no, FBI is not in the storage business and there are no witnesses to protect.

However, SMB 3.0 has introduced a RPC-based mechanism to inform the clients of any state change in the SMB servers. Microsoft calls it Service Witness Protocol [SWP], and its objective is provide a much faster notification service allow the SMB 3.0 clients to do a failover. In previous SMB 1.0 and even in SMB 2.x, the SMB clients rely on time-out services. The time-out services, either SMB or TCP, could take up as much as 30-45 seconds, and this creates a high latency that is disruptive to enterprise applications.

SMB 3.0, as mentioned in my previous post, had a total revamp, and is now enterprise ready. In what Microsoft calls “Continuously Available” File Service, the SMB 3.0 supports clustered or scale-out file servers. The SMB shares must be shared as “Continuously Available” shares and mapped to SMB 3.0 clients. As shown in the diagram below (provided by SNIA’s webinar),

SMB 3.0 CA Shares

Client A mapping to Server 1 share (\\srv1\CAshr). Client A has a share “handle” that establishes a connection with a corresponding state of the session. The state of the session is synchronously kept consistent with a corresponding state in Server 2.

The Service Witness Protocol is not responsible for the synchronization of the states in the SMB file server cluster. Microsoft has left the HA/cluster/scale-out capability to the proprietary technology method of the NAS vendor. However, SWP regularly observes the status of all services under its watch. Continue reading

Has Object Storage become the everything store?

I picked up a copy of latest Brad Stone’s book, “The Everything Store: Jeff Bezos and the Age of Amazon at the airport on my way to Beijing last Saturday. I have been reading it my whole time I have been in Beijing, reading in awe about the turbulent ups and downs of Amazon.com.

The Everything Store cover

In its own serendipitous ways, Object-based Storage Devices (OSDs) have been floating in my universe in the past few weeks. Seems like OSDs have been getting a lot of coverage lately and suddenly, while in the shower, I just had an epiphany!

Are storage vendors now positioning Object-based Storage Devices (OSDs) as Everything Store?

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Novell Filr Technology Overview – Part 2

Part 1 of the Novell Filr Technology Overview was too heavy and I had to break up to share the feature of storage.

How will storage space look like to the different access methods or mobile device? Novell Filr does not deviate from the comfortable interface that is functionally similar to applications such as Dropbox. Under the guise of folders and files, the interface is a familiar one. It is called “MY FILES”.

But under the wraps of “MY FILES”, Novell Filr consolidates both Personal Storage and Net Folders locations under one roof. Here’s a look at “MY FILES” and how it consolidates various underlying file storage structure:

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Novell Filr Technology Overview Part 1

I am like a kid opening presents on Christmas mornings today.

Reading and understanding the Novell Filr architecture is exciting with each feature revealing something different, some that may not be entirely unique, but something done simplified. Novell Filr has simplified a few things that are much more appreciated from storage guys like me. Let me share with you this technology learning session.

2 Key Features

First of all, I see the Novell Filr as a Secure Access Broker.

The Novell Filr provides file access, file sharing and file synchronization with multiple mobile devices. The mobility revolution in the likes of smart phones, tablets and other “connected” devices in our personal lives are changing our habits in the way we want information to be accessed, which I can summarize in 2 words – SIMPLE, UNINHIBITED. It is the lack of inhibition that scares the hell out of IT because IT is losing control, and corporations fear data leaks.

Novell Filr lets users access their home directories and network folders from their mobile devices. It lets the users synchronize their files with Windows and MacOS computers, regardless if these devices are internal of the company’s firewalled networks or external of it. Here’s a simple diagram of how Novell Filr defines its position as a Secure Access Broker.

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And Cloud Storage will make us even stranger

It was a dark and stormy night ….

I was in a car with my host in the stifling traffic jams on the streets of Jakarta. We had just finished dinner and his driver was taking me back to the hotel. It was about 9pm and we were making conversation trying to figure out how we can work together. My host, a wonderful Singaporean who has been residing in Jakarta for more than a decade and a half, owns a distributorship focusing mainly on IT security solutions. He had invited me over to Jakarta to give a talk on Cloud Storage at the Indonesia CIO Network event on January 9th 2013.

I was there to represent SNIA South Asia to give a talk about CDMI (Cloud Data Management Interface), and my host also took the opportunity to introduce Nutanix, a SAN-less 2-tier, high-performance, virtualized data center platform. (Note: That’s quite a mouthful, but gotta include all the buzz-words in there). It was my host’s first foray into storage networking solutions, away from his usual security solutions spread. As the conversation went on in the car, he said “You storage guys are so strange!“.

To many of the IT folks who have been involved in OS, applications, security, and networking, to say a few, storage is like a dark art, some mumbo jumbo, voodoo-like science known to a select few. That’s great, because this perception will keep us relevant, and still have the value and a job. To me, that just fine and dandy, and I like it that way. 🙂

In preparation to the event, I have to learn up SNIA CDMI. Cloud and Storage … Cloud and Storage … Cloud and Storage. Hmmm …. Continue reading

APIs that stick in Storage

The competition in storage networking and data management is forever going to get fiercer. And there is always going to be the question of either having open standards APIs or proprietary APIs because storage networking and data management technologies constantly have to balance between gaining a competitive advantage with proprietary APIs  or getting greater market acceptance with open standards APIs.

The flip side, is having proprietary APIs could limit and stunt the growth of the solution but with much better integration and interoperability with complementary solutions. Open standards APIs could make the entire market a plain, vanilla one where there is little difference between technology A or B or C or X, and in the long run, could give lesser incentive for technology innovation.

I am not an API guy. I do not code or do development work on APIs, but I do like APIs (Application Programming Interface). I have my fair share of APIs which can be considered open or proprietary depending on who you talk to. My understanding is that an API might be more open if there are many ISVs, developers and industry supporters endorsing it and have a valid (and usually profit-related) agenda to make the API open.

I can share some work experience with some APIs I have either worked in the past or give my views of some present cool APIs that are related to storage networking and data management.

One of the API-related works I did was with the EMC Centera. I was working with Schlumberger to create a file-level archiving/lifecycle management solution for the GeoFrame seismic files with the EMC Centera. This was back in 2008.

EMC Centera does not present itself as a NAS box (even though I believe, IDC lumps Centera sales numbers to worldwide NAS market figures, unless I am no longer correct chronologically) but rather through ISVs and application-level integration with the EMC Centera API. Here’s a high-level look of how the EMC Centera talks to application with the API.

Note: EMC Centera can also present a NAS integration interface through NFS, CIFS, HTTP and FTP protocols, but the customer must involve (may have to purchase) the EMC Centera Universal Access software appliance. This is for applications that do not have the level of development and integration to interface with the EMC Centera API. 

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