Layers in Storage – For better or worse

Storage arrays and storage services are built upon by layers and layers beneath its architecture. The physical components of hard disk drives and solid states are abstracted into RAID volumes, virtualized into other storage constructs before they are exposed as shares/exports, LUNs or objects to the network.

Everyone in the storage networking industry, is cognizant of the layers and it is the foundation of knowledge and experience. The public cloud storage services side is the same, albeit more opaque. Nevertheless, both have layers.

In the early 2000s, SNIA® Technical Council outlined a blueprint of the SNIA® Shared Storage Model, a framework describing layers and properties of a storage system and its services. It was similar to the OSI 7-layer model for networking. The framework helped many industry professionals and practitioners shaped their understanding and the development of knowledge in their respective fields. The layering scheme of the SNIA® Shared Storage Model is shown below:

SNIA Shared Storage Model – The layering scheme

Storage vendors layering scheme

While SNIA® storage layers were generic and open, each storage vendor had their own proprietary implementation of storage layers. Some of these architectures are simple, but some, I find a bit too complex and convoluted.

Here is an example of the layers of the Automated Volume Management (AVM) architecture of the EMC® Celerra®.

EMC Celerra AVM Layering Scheme

I would often scratch my head about AVM. Disks were grouped into RAID groups, which are LUNs (Logical Unit Numbers). Then they were defined as Celerra® dvols (disk volumes), and stripes of the dvols were consolidated into a storage pool.

From the pool, a piece of a storage capacity construct, called a slice volume, were combined with other slice volumes into a metavolume which eventually was presented as a file system to the network and their respective NAS clients. Explaining this took an effort because I was the IP Storage product manager for EMC® between 2007 – 2009. It was a far cry from the simplicity of NetApp® ONTAP 7 architecture of RAID groups and volumes, and the WAFL® (Write Anywhere File Layout) filesystem.

Another complicated layered framework I often gripe about is Ceph. Here is a look of how the layers of CephFS is constructed.

Ceph Storage Layered Framework

I work with the OpenZFS filesystem a lot. It is something I am rather familiar with, and the layered structure of the ZFS filesystem is essentially simpler.

Storage architecture mixology

Engineers are bizarre when they get too creative. They have a can do attitude that transcends the boundaries of practicality sometimes, and boggles many minds. This is what happens when they have their own mixology ideas.

Recently I spoke to two magnanimous persons who had the idea of providing Ceph iSCSI LUNs to the ZFS filesystem in order to use the simplicity of NAS file sharing capabilities in TrueNAS® CORE. From their own words, Ceph NAS capabilities sucked. I had to draw their whole idea out in a Powerpoint and this is the architecture I got from the conversation.

There are 3 different storage subsystems here just to provide NAS. As if Ceph layers aren’t complicated enough, the iSCSI LUNs from Ceph are presented as Cinder volumes to the KVM hypervisor (or VMware® ESXi) through the Cinder driver. Cinder is the persistent storage volume subsystem of the Openstack® project. The Cinder volumes/hypervisor datastore are virtualized as vdisks to the respective VMs installed with TrueNAS® CORE and OpenZFS filesystem. From the TrueNAS® CORE, shares and exports are provisioned via the SMB and NFS protocols to Windows and Linux respectively.

It works! As I was told, it worked!

A.P.P.A.R.M.S.C. considerations

Continuing from the layered framework described above for NAS, other aspects beside the technical work have to be considered, even when it can work technically.

I often use a set of diligent data storage focal points when considering a good storage design and implementation. This is the A.P.P.A.R.M.S.C. Take for instance Protection as one of the points and snapshot is the technology to use.

Snapshots can be executed at the ZFS level on the TrueNAS® CORE subsystem. Snapshots can be trigged at the volume level in Openstack® subsystem and likewise, rbd snapshots at the Ceph subsystem. The question is, which snapshot at which storage subsystem is the most valuable to the operations and business? Do you run all 3 snapshots? How do you execute them in succession in a scheduled policy?

In terms of performance, can it truly maximize its potential? Can it churn out the best IOPS, and deliver at wire speed? What is the latency we can expect with so many layers from 3 different storage subsystems?

And supporting this said architecture would be a nightmare. Where do you even start the troubleshooting?

Those are just a few considerations and questions to think about when such a layered storage architecture along. IMHO, such a design was over-engineered. I was tempted to say “Just because you can, doesn’t mean you should

Elegance in Simplicity

Einstein (I think) quoted:

Einstein’s quote on simplicity and complexity

I am not saying that having too many layers is wrong. Having a heavily layered architecture works for many storage solutions out there, where they are often masked with a simple and intuitive UI. But in yours truly point of view, as a storage architecture enthusiast and connoisseur, there is beauty and elegance in simple designs.

The purpose here is to promote better understanding of the storage layers, and how they integrate and interact with each other to deliver the data services to the network. In the end, that is how most storage architectures are built.

 

Fueling the Flywheel of AWS Storage

It was bound to happen. It happened. AWS Storage is the Number 1 Storage Company.

The tell tale signs were there when Silicon Angle reported that AWS Storage revenue was around USD$6.5-7.0 billion last year and will reach USD$10 billion at the end of 2021. That news was just a month ago. Last week, IT Brand Pulse went a step further declaring AWS Storage the Number 1 in terms of revenue. Both have the numbers to back it up.

AWS Logo

How did it become that way? How did AWS Storage became numero uno?

Flywheel juggernaut

I became interested in the Flywheel concept some years back. It was conceived in Jim Collins’ book, “Good to Great” almost 20 years ago, and since then, Amazon.com has become the real life enactment of the Flywheel concept.

Amazon.com Flywheel – How each turn becomes sturdier, brawnier.

Every turn of the flywheel requires the same amount of effort although in the beginning, the noticeable effect is minuscule. But as every turn gains momentum, the returns of each turn scales greater and greater to the fixed efforts of operating a single turn.

Continue reading

Storageless shan’t be thy name

Storageless??? What kind of a tech jargon is that???

This latest jargon irked me. Storage vendor NetApp® (through its acquisition of Spot) and Hammerspace, a metadata-driven storage agnostic orchestration technology company, have begun touting the “storageless” tech jargon in hope that it will become an industry buzzword. Once again, the hype cycle jargon junkies are hard at work.

Clear, empty storage containers

Clear, nondescript storage containers

It is obvious that the storageless jargon wants to ride on the hype of serverless computing, an abstraction method of computing resources where the allocation and the consumption of resources are defined by pieces of programmatic code of the running application. The “calling” of the underlying resources are based on the application’s code, and thus, rendering the computing resources invisible, insignificant and not sexy.

My stand

Among the 3 main infrastructure technology – compute, network, storage, storage technology is a bit of a science and a bit of dark magic. It is complex and that is what makes storage technology so beautiful. The constant innovation and technology advancement continue to make storage as a data services platform relentlessly interesting.

Cloud, Kubernetes and many data-as-a-service platforms require strong persistent storage. As defined by NIST Definition of Cloud Computing, the 4 of the 5 tenets – on-demand self-service, resource pooling, rapid elasticity, measured servicedemand storage to be abstracted. Therefore, I am all for abstraction of storage resources from the data services platform.

But the storageless jargon is doing a great disservice. It is not helping. It does not lend its weight glorifying the innovations of storage. In fact, IMHO, it felt like a weighted anchor sinking storage into the deepest depth, invisible, insignificant and not sexy. I am here dutifully to promote and evangelize storage innovations, and I am duly unimpressed with such a jargon.

Continue reading

TrueNAS – The Secure Data Platform for EasiShare

The Enterprise File Sync and Share (EFSS) EasiShare presence is growing rapidly in the region, as enterprises and organizations are quickly redefining the boundaries of the new workspace. Work files and folders are no longer confined to the shared network drives within the local area network. It is going beyond to the “Work from Anywhere” phenomenon that is quickly becoming the way of life. Breaking away from the usual IT security protection creates a new challenge, but EasiShare was conceived with security baked into its DNA. With the recent release, Version 10, file sharing security and resiliency are stronger than ever.

[ Note: I have blogged about EasiShare previously. Check out the 2 links below ]

Public clouds are the obvious choice but for organizations to protect their work files, and keep data secure, services like Dropbox for Business, Microsoft® Office 365 with OneDrive and Google® Workspace are not exactly the kind of file sharing with security as their top priority. A case in point was the 13-hour disruption to Wasabi Cloud last week, where the public cloud storage provider’s domain name, wasabisys.com, was suspended by their domain name registrar because of malware discrepancy at one of its endpoints. There were other high profile cases too.

This is where EasiShare shines, because it is a secure, private EFSS solution for the enterprise and beyond, because business resiliency is in the hands and control of the organization that owns it, not the public cloud service providers.

EasiShare unifies with TrueNAS for secure business resiliency

EasiShare is just one several key business solutions iXsystems™ in Asia Pacific Japan is working closely with, and there is a strong, symbiotic integration with the TrueNAS® platform. Both have strong security features that fortify business resiliency, especially when facing the rampant ransomware scourge.

Value of a Single Unified Data Services Platform

A storage array is not a solution. It is just a box that most vendors push to sell. A storage must be a Data Services Platform. Readers of my blog would know that I have spoken about the Data Services Platform 3 years ago and you can read about it:

Continue reading

Kubernetes Persistent Storage Managed Well

[ Disclosure: This is a StorPool Storage sponsored blog ]

StorPool Storage – Distributed Storage

There is a rapid adoption of Kubernetes in the enterprise and in the cloud. The push for digital transformation to modernize businesses for a cloud native world in the next decade has lifted both containerized applications and the Kubernetes container orchestration platform to an unprecedented level. The application landscape, especially the enterprise, is looking at Kubernetes to address these key areas:

  • Scale
  • High performance
  • Availability and Resiliency
  • Security and Compliance
  • Controllable Costs
  • Simplified

The Persistent Storage Question

Enterprise applications such as relational databases, email servers, and even the cloud native ones like NoSQL, analytics engines, demand a single data source of truth. Fundamentals properties such as ACID (atomicity, consistency, isolation, durability) and BASE (Basic Availability, Soft State, Eventual Consistency) have to have persistent storage as the foundational repository for the data. And thus, persistent storage have rallied under Container Storage Interface (CSI), and fast becoming a de facto standard for Kubernetes. At last count, there are more than 80 CSI drivers from 60+ storage and cloud vendors, each providing block-level storage to Kubernetes pods.

However, at this juncture, Kubernetes is still very engineering-centric. Persistent storage is equally as challenging, despite all the new developments and hype around it.

Continue reading

A Paean to NFS

It is certainly encouraging to see both NAS protocols, NFS and SMB, featured well in the latest VMware® vSAN 7 Update 1 release. The NFS v3 and v4.1 support was already in vSAN 7.0 when it was earlier announced as part of its Native File Services for vSAN. But some years ago, NFS was not always the primary storage protocol of choice. SAN protocols, Fibre Channel and iSCSI, were almost always designated to serve enterprise applications. At the client side, Windows became prominent, and the SMB/CIFS protocol dominated the landscape of the desktop. This further pushed NFS into the back closet.

NFS or Network File System has its naysayers. The venerable, but often maligned distributed network file protocol is 36 years today. In storage vendors such as NetApp®, VAST Data, Pure Storage FlashBlade, and Dell EMC Isilon, NFS is still positioned as the primary file protocol for manufacturing testers on the shop floor, EDA/eCAD applications, seismic and subsurface applications in Oil & Gas and many more. In another development, just like its presence in the vSAN Native Services,, NFS has also quietly embedded itself into many storage platforms to serve the data platform services within the respective framework itself.

And I have experienced NFS from the client side to the enterprise applications and more, and I take this opportunity to pay tribute.

NFS (Network File System) client server network

NFS (Network File System) client server network

Continue reading

Storage in a shiny multi-cloud space

The multi-cloud for infrastructure-as-a-service (IaaS) era is not here (yet). That is what the technology marketers want you to think. The hype, the vapourware, the frenzy. It is what they do. The same goes to technology analysts where they describe vision and futures, and the high level constructs and strategies to get there. The hype of multi-cloud is often thought of running applications and infrastructure services seamlessly in several public clouds such as Amazon AWS, Microsoft® Azure and Google Cloud Platform, and linking it to on-premises data centers and private clouds. Hybrid is the new black.

Multicloud connectivity to public cloud providers and on-premises private cloud

Multi-Cloud, on-premises, public and hybrid clouds

And the aspiration of multi-cloud is the right one, when it is truly ready. Gartner® wrote a high level article titled “Why Organizations Choose a Multicloud Strategy“. To take advantage of each individual cloud’s strengths and resiliency in respective geographies make good business sense, but there are many other considerations that cannot be an afterthought. In this blog, we look at a few of them from a data storage perspective.

In the beginning there was … 

For this storage dinosaur, data storage and compute have always coupled as one. In the mainframe DASD days. these 2 were together. Even with the rise of networking architectures and protocols, from IBM SNA, DECnet, Ethernet & TCP/IP, and Token Ring FC-SAN (sorry, this is just a joke), the SANs, the filers to the servers were close together, albeit with a network buffered layer.

A decade ago, when the public clouds started appearing, data storage and compute were mostly inseparable. There was demarcation of public clouds and private clouds. The notion of hybrid clouds meant public clouds and private clouds can intermix with on-premise computing and data storage but in almost all cases, this was confined to a single public cloud provider. Until these public cloud providers realized they were not able to entice the larger enterprises to move their IT out of their on-premises data centers to the cloud convincingly. So, these public cloud providers decided to reverse their strategy and peddled their cloud services back to on-prem. Today, Amazon AWS has Outposts; Microsoft® Azure has Arc; and Google Cloud Platform launched Anthos.

Continue reading

Give back or no give

[ Disclosure: I work for iXsystems™ Inc. Views and opinions are my own. ]

If my memory served me right, I recalled the illustrious leader of the Illumos project, Garrett D’Amore ranting about companies, big and small, taking OpenZFS open source codes and projects to incorporate into their own technology but hardly ever giving back to the open source community. That was almost 6 years ago.

My thoughts immediately go back to the days when open source was starting to take off back in the early 2000s. Oracle 9i database had just embraced Linux in a big way, and the book by Eric S. Raymond, “The Cathedral and The Bazaar” was a big hit.

The Cathedral & The Bazaar by Eric S. Raymond

Since then, the blooming days of proprietary software world began to wilt, and over the next twenty plus year, open source software has pretty much taken over the world. Even Microsoft®, the ruthless ruler of the Evil Empire caved in to some of the open source calls. The Microsoft® “I Love Linux” embrace definitely gave the victory feeling of the Rebellion win over the Empire. Open Source won.

Open Source bag of worms

Even with the concerted efforts of the open source communities and projects, there were many situations which have caused frictions and inadvertently, major issues as well. There are several open source projects licenses, and they are not always compatible when different open source projects mesh together for the greater good.

On the storage side of things, 2 “incidents” caught the attention of the masses. For instance, Linus Torvalds, Linux BDFL (Benevolent Dictator for Life) and emperor supremo said “Don’t use ZFS” partly due to the ignorance and incompatibility of Linux GPL (General Public License) and ZFS CDDL (Common Development and Distribution License). That ruffled some feathers amongst the OpenZFS community that Matt Ahrens, the co-creator of the ZFS file system and OpenZFS community leader had to defend OpenZFS from Linus’ comments.

Continue reading

FreeNAS 11.2 & 11.3 eBook

[ Full disclosure: I work for iXsystems™ Inc. This eBook was 3/4 completed when I joined on July 1, 2020 ]

I am releasing my FreeNAS™ eBook today. It was completed about 4 weeks ago, but I wanted the release date to be significant which is August 31, 2020.

FreeNAS logo

Why August 31st? Because today is Malaysia’s Independence Day.

Why the book?

I am an avid book collector. To be specific, IT and storage technology related books. Since I started working on FreeNAS™ several years ago, I wanted to find a book to learn. But the FreeNAS™ books in the market are based on an old version of FreeNAS™. And the FreeNAS™ documentation is a User Guide where it explains every feature without going deeper with integration of real life networking services, and situational applications such as SMB or NFS client configuration.

Since I have been doing significant amount of feature “testings” of FreeNAS™ from version 9.10 till the present version 11,3 on Virtualbox™, I have decided to fill that gap. I have decided to write a cookbook-style FreeNAS™ on Virtualbox™ that covers most of the real-life integration work with various requirements including Active Directory, cloud integration and so on. All for extending beyond the FreeNAS™ documentation.

Continue reading