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Is Dell Fluid Enough?

Dell made a huge splash 2 weeks ago in London in their inaugural Dell Storage Forum. They dubbed their storage and management lineup as “Fluid Data Architecture” offering the ability for customers to quickly adapt and automate their business when it comes to storage networking and more importantly, data management.

In the London show, they showcased several key innovations and product development. Here’s a list of their jewels:

  • DR4000 – an inline, content optimized backup deduplication appliance (based on the acquired technology of Ocarina Networks)
  • Compellent Storage Center 6.0 – a major software release
  • Compellent key technology integration with VMware
  • Optimized object storage for Microsoft Sharepoint with the DX6000 Object Storage Platform – DX6000 is an OEM from Caringo
  • Broader support for Dell Force10, PowerConnect and their partner’s Brocade

The technology from Ocarina Networks is fantastic technology and I have always admired Ocarina. I have written about Ocarina in the past in my previous blog. But I was a bit perplexed why Dell chose to enter the secondary dedupe market with a backup dedupe appliance in the DR4000. They are already a latecomer into the secondary deduplication game and I thought HP was already late with their StoreOnce.

They could have used Ocarina’s technology to trailblaze the primary deduplication market. In my previous blog, I mentioned that primary deduplication hasn’t really taken off in a big way, and Dell with the technology from Ocarina could set the standard and establish themselves as the leader of the primary deduplication market space. I was disappointed that they didn’t, not just yet.

The Compellent Storage Center 6.0 release was a major release and it was, for better or for worse, coincided with the departure of Phil Soran, the founder and CEO of Compellent. Phil felt that he can let his baby go and Dell is certainly making the best of what they can do with Compellent as their flagship data storage product.

The major release included 64-bit support for greater performance and scalability and also include several key VMware technologies that other vendors already have. The technologies included:

  • VMware vStorage API for Array Integration (VAAI)
  • Storage Replication Adapter plug-in for VMware Site Recovery Manager (SRM)
  • VSphere 5 client plug-in
  • Integration of Enterprise Manager and VSphere

Other storage related releases (I am not going to talk about Force10 or their PowerConnect solutions here) included Dell offering 16Gbps FibreChannel switches from Brocade and also their DX6000 Object Storage Platform optimized for Microsoft Sharepoint.

I think it is fantastic that Dell is adapting and evolving into a business-oriented, enterprise solution provider and their acquisitions in the past 3 years – EqualLogic, Exanet, Ocarina Networks, Force10 and Compellent – proves that Dell aims to take market share in the storage networking and data management market. They have key initiatives with CommVault, Symantec, VMware and Microsoft as well. And Michael Dell is becoming quite a celebrity lately, giving Dell the boost it needs to battle in this market.

But the question is, “Is their Fluid Data Architecture” fluid enough?” If I were a customer, would I bite?

As a customer, I look for completeness in the total solution, and I cannot fault Dell for having most of the pieces in the solution stack. They have networking in their PowerConnect, Force10 and Brocade. They have SAN in both Compellent and EqualLogic but their unified storage story is still a bit lacking. That’s because we have not seen Dell’s NAS storage yet. Exanet was a scale-out NAS and we have seen little rah-rah about this product.

From a data management perspective, their data protection story gels well with the Commvault and Symantec partnership, but I feel that Dell sales and SEs (at least in Malaysia) spends too much time touting the Compellent Automated Storage Tiering. I have spoken to folks who have listened to Dell guys’ pitches and it’s too one-dimensional. It’s always about storage tiering and little else about other Compellent technology.

At this point of time, the story that Dell sells here in Malaysia is still disjointed, but they are getting better. And eventually, the fluidity (pun intended ;-)) of their Fluid Data Architecture will soon improve.

How will Dell fare in 2012? They had taken a beating in the past 2 IDC’s quarter storage market tracker, losing some percentage points in market share but I think Dell will continue to tinker to get it right.

2012 will be their watershed year.



This is Part 2 of my previous blog about VAAI (vStorage API for Array Integration) with more details about VAAI. VAAI offloads some of the I/O related functions to the VAAI-enable storage array, hence giving the hypervisor more compute and memory resource to do it other functions. And the storage array, upon receiving the VAAI command, will execute whatever that is required of it.

Why is VAAI important? What does it do that makes it so useful and important to the hypervisor?

VAAI is about a set of new SCSI commands. And there are 3 important ones:

  • XSET
  • ATS
What exactly do these SCSI commands do?
WRITE-SAME is a SCSI command that instructs the storage array to zeroes the virtual VMDK disks or VMFS LUNs. This usually happens when guest OS require a brand new set of virtual disks and initializing the virtual disks is required. In the past (before VAAI), the hypervisor has to repetitively send 0s to the storage to perform the disks zeroing. As shown in the diagram below, you can see that each zero operation is sent from the hypervisor to the storage.
This back-and-forth of sending 0s and acknowledgments between the hypervisor and the storage is not efficient. With VAAI, the command WRITE-SAME  is sent from the hypervisor to the storage array and the storage array will do the zeroing on the disks and LUNs. The hypervisor will not intervene with the process until it gets and acknowledgment of its completion. See diagram below of how VAAI helps in bulk-zeroing of disks and LUNs in the storage array.
The animated GIFs are the taken from Luke Reed’s blog, a fantastic read.
The second VAAI SCSI command is XSET and it performs hardware accelerated full copy. This command is also known as  XCOPY and it offloads the process of copying the blocks of data that makeup a VMDK file. Such copying operations occur when the hypervisor is doing things like VM cloningStorage vMotion or VM creation from templates (bulk copying to create many similar VMs in one go).
Again with the courtesy of Luke Reed’s animated GIFs, the diagram below shows a full copy without VAAI
and after implementing VAAI, where the full, bulk copy operations is offloaded to the storage array to execute.
The third and last SCSI command of VAAI is ATS or hardware-assisted locking. ATS stands for Atomic, Test and Set and the command allow the hypervisor to lock only the required blocks rather than the entire LUN.
Without VAAI, the entire LUN temporarily could be locked by the numerous VMFS operations of one single hypervisor and this prevents other hypervisors from accessing the shared LUNs. The ATS API offloads lock management from the host to the storage array and keeps the LUN available by locking only required blocks, not the entire VMFS file system. Please see the pleasing diagrams below of
(without VAAI ATS)
(with VAAI ATS)

And if you want to see the VAAI Hardware Accelerated Full Copy (aka XSET) in action, here’s a little video showing how it is done in an EMC environment.

The primary significance and noticeable benefit is definitely performance. The secondary benefit, though not so obvious, is allowing VMware and its hypervisor to scale because it does not get bogged down by some of the I/O functions that it is not meant to do.

There were some new additions in vSphere 5.0 for VAAI. From its FAQ, it listed in ESX5.0, support for NAS Hardware Acceleration is included with support for the following primitives:

  • Full File Clone – Like the Full Copy VAAI primitive provided for block arrays, this Full File Clone primitive enables virtual disks to be cloned by the NAS device.
  • Native Snapshot Support – Allows creation of virtual machine snapshots to be offloaded the array.
  • Extended Statistics – Enables visibility to space usage on NAS datastores and is useful for Thin Provisioning.
  • Reserve Space – Enables creation of thick virtual disk files on NAS.

So, there you have it folks. Why VAAI? Here’s why.

VAAI to go!

First of all, let me apologize. I am guilty of not updating my blogs as regularly as I did in the past. Things got a bit crazy after Christmas and I had to juggle several things that demand more of my attention but I am confident things will sort itself out soon enough.

Today’s topic is about VMware’s VAAI (vSphere vStorage API for Array Integration). This feature was announced more than 3 years ago but was only introduced in vSphere 4.1 July 2010 and now with newer enhancements in the latest release of vSphere 5.0.

What is this VAAI and what does this mean from a storage perspective?

When VMware came into prominence in version 3.0/3.5 time, the whole world revolved around the ESX hypervisor. It tried to do everything on its own, in its own proprietary nature. Given its nascent existence then, ESX had to do what it had to do and control everything with its hypervisor universe. Yes, it was a good move then and it did what it was supposed to do. This was back when server virtualization was in its infancy, and resources requirements were less demanding.

Hence when VMware wants to initialize VMs, or create VMDK files on the datastore, or creating clones or snapshots, or even executing VMotion and Storage VMotion, it tends to execute it at the hypervisor level. For example, when creating virtual disks with VMFS, most of the commands to initialization of the disks were done at the VMFS level. Zeroing the virtual disks would mean sending zeroing commands to the actual physical disks on the shared storage. And this would go on back and forth, taxing the CPU cycles and memory on the hypervisor layer, and sending wasteful and unnecessary zeroes over the network to the storage array. This was very inefficient, wasteful and degrades the performance tremendously, especially at the hypervisor layer (compute and memory).

There are also other operations such as virtual disks locking that locks up the entire LUN that housed several datastores. Again, not good.

But VMware took off like a rocket, and quickly established itself as a Tier 1, enterprise server virtualization solution addressing the highest demands of the enterprise. It is also defining the future of Cloud Computing, building exorbitant requirements as it pushes forward. And VMware began to realize that if the hypervisor is to scale, it needs to leave the I/O operations to the “experts”, and the “experts” here being the respective storage array itself.

So, in version 4.1, VAAI (vStorage API for Array Integration) was introduced as an API suite, following 3 other earlier APIs – vStorage API for Site Recovery Manager (SRM), vStorage API for Data Protection and vStorage API for Multipathing.

In a nutshell, as I have mentioned before, VAAI offloads I/O and storage related operations to the VAAI-capable storage array (leave it to the experts) as shown in the diagram below:

Of course, the storage vendors themselves has to rework their array OS layer to integrate with the VAAI API. You can say that the VAAI are “hooks” that enhances the storage connectivity and communications with vSphere’s hypervisor. But then again, if you look at it from the other angle, vSphere need the storage vendors more in order for its universe to scale. Good thing VMware has a big, big market share. Imagine if there are no takers for the VAAI APIs. That would be a strange predicament instead.

What is the big deal that we get from VAAI? The significant and noticeable benefit is increase performance. By offloading the I/O functionality and operations to the storage array itself, the hypervisor and the compute and memory resource are not bogged down, resulting in higher performance and better response time to serve its VMs and other VM operations.

I am going off to another meeting and I shall write of VAAI in more details later. Until the next entry, adios and have a great year ahead.

NetApp to buy Commvault?

The rumour mill is going again that Commvault is an acquisition target, and this time, NetApp. The rumour is not new but someone Commvault has gotten too big in the past couple of years to be swallowed up. But this time, it could happen as NetApp is hungry, …. very hungry.

NetApp took a big hit a couple of weeks back, when it announced its Q3 numbers. Revenues fell short of analysts expectations and the share price took a big hit. While its big rival, EMC, has been gaining much momentum on all fronts, it appears that NetApp is getting overwhelmed by the one-stop-shop of EMC. EMC is everything to everyone who wants storage, data protection software, services, data management, scale-out, data security, big data, cloud storage and virtualization and much more. NetApp, has been very focused on what they do best, and that is storage. Everything evolves around their crown jewel, Data ONTAP and recently added Engenio to their stable of storage solutions.

NetApp does not mix the FAS storage with the Engenio and making sure that their story-telling gels but in the past few years, many other vendors are taking the “one-stack-fits-all” approach. Oracle have Exadata, where servers, storage, database and networking in all-in-one. Many others are doing the same, while NetApp prefers a more “loose-coupled” partnerships, such as their “Imagine Virtually Anything” concept partnership with VMware and Cisco, in the shape of FlexPod. FlexPod is a flexible infrastructure package comprising presized storage, networking and server components designed to ease the IT transformation journey–from virtualization all the way to cloud computing.

Commvault would be a great buy (going to be very expensive buy) for NetApp. Things fits perfectly if NetApp decides to abandon its overly protective shield and start becoming a “one-stop-shop” to its customers, starting with data protection. Commvault is already the market leader in the Enterprise Disk-based Backup and Recovery market, and well reflected in Gartner’s Magic Quadrant January 2011 report.

It’s amazing to see how Commvault got to become the leader in this space in just a few short years, and part of its unique approach is providing a common core engine called the Common Technology Engine (CTE). The singular core architecture allows different data management components – Backup, Replication, Archiving, Resource Management and Classification & Search – to share resource and more importantly detailed knowledge of true data management.

In the middle of this year, NetApp had an OEM deal with Commvault to resell their SnapProtect solution, which integrates with NetApp’s SnapMirror solution. The SnapProtect manages NetApp snapshots and SnapMirror replications and also enhances the solution as a tape-out for SnapMirror. Below shows how the Commvault SnapProtect fits into NetApp’s snapshots and SnapMirror data protection architecture.

Sources of NetApp’s C-Level said that NetApp is still very much focused on their ONTAP strategy and with their “loosely-coupled” partnerships with key partners like VMware, Cisco, F5 and Quantum. But at the back of NetApp’s mind, I believe, it is time to do something about it. This “focused” (also could be interpreted an overly cautious) approach is probably seeing the last leg of its phase as cloud computing is changing all that. The cost of integration of different, yet flexible components of storage, data protection and data management components, is prohibitive to cloud service providers and NetApp must take a bolder approach to win the hearts of these providers. Having a one-stop-shop isn’t so bad anymore; it is beginning to make sense and NetApp had better do something quick. Commvault is one of the best out there and NetApp shouldn’t lose that chance.

Note: While the rumours of NetApp and Commvault are swirling, there’s been rumours that Quantum could be another NetApp target. 

A cloud economy emerges … somewhat

A few hours ago, Rackspace had just announced the first “productized” Rackspace Private Cloud solution based on OpenStack. According to,

OpenStack OpenStack is a global collaboration of developers and cloud computing 
technologists producing the ubiquitous open source cloud computing platform for 
public and private clouds. The project aims to deliver solutions for all types of 
clouds by being simple to implement, massively scalable, and feature rich. 
The technology consists of a series of interrelated projects delivering various 
components for a cloud infrastructure solution.

Founded by Rackspace Hosting and NASA, OpenStack has grown to be a global software 
community of developers collaborating on a standard and massively scalable open 
source cloud operating system. Our mission is to enable any organization to create 
and offer cloud computing services running on standard hardware. 
Corporations, service providers, VARS, SMBs, researchers, and global data centers 
looking to deploy large-scale cloud deployments for private or public clouds 
leveraging the support and resulting technology of a global open source community.
All of the code for OpenStack is freely available under the Apache 2.0 license. 
Anyone can run it, build on it, or submit changes back to the project. We strongly 
believe that an open development model is the only way to foster badly-needed cloud 
standards, remove the fear of proprietary lock-in for cloud customers, and create a 
large ecosystem that spans cloud providers.

And Openstack just turned 1 year old.

So, what’s this Rackspace private cloud about?

In the existing cloud economy, customers subscribe from a cloud service provider. The customer pays a monthly (usually) subscription fee in a pay-as-you-use-model. And I have courageously predicted that the new cloud economy will drive the middle tier (i.e. IT distributors, resellers and system integrators) in my previous blog out of IT ecosystem. Before I lose the plot, Rackspace is now providing the ability for customers to install an Openstack-ready, Rackspace-approved private cloud architecture in their own datacenter, not in Rackspace Hosting.

This represents a tectonic shift in the cloud economy, putting the control and power back into the customers’ hands. For too long, there were questions about data integrity, security, control, cloud service provider lock-in and so on but with the new Rackspace offering, customers can build their own private cloud ecosystem or they can get professional service from Rackspace cloud systems integrators. Furthermore, once they have built their private cloud, they can either manage it themselves or get Rackspace to manage it for them.

How does Rackspace do it?

From their vast experience in building Openstack clouds, Rackspace Cloud Builders have created a free reference architecture.  Currently OpenStack focuses on two key components: OpenStack Compute, which offers computing power through virtual machine and network management, and OpenStack Object Storage, which is software for redundant, scalable object storage capacity.

In the Openstack architecture, there are 3 major components – Compute, Storage and Images.


More information about the Openstack Architecture here. And with 130 partners in the Openstack alliance (which includes Dell, HP, Cisco, Citrix and EMC), customers have plenty to choose from, and lessening the impact of lock-in.

What does this represent to storage professionals like us?

This Rackspace offering is game changing and could perhaps spark an economy for partners to work with Cloud Service Providers. It is definitely addressing some key concerns of customers related to security and freedom to choose, and even change service providers. It seems to be offering the best of both worlds (for now) but Rackspace is not looking at this for immediate gains. But we still do not know how this economic pie will grow and how it will affect the cloud economy. And this does not negate the fact that us storage professionals have to dig deeper and learn more and this not does change the fact that we have to evolve to compete against the best in the world.

Rackspace has come out beating its chest and predicted that the cloud computing API space will boil down these 3 players – Rackspace Openstack, VMware and Amazon Web Services (AWS). Interestingly, Redhat Aeolus (previously known as Deltacloud) was not worthy to mentioned by Rackspace. Some pooh-pooh going on?

Signs of things to come?

I wanted to sign off early tonight but an article in ComputerWorld caught my tired eyes. It was titled “EMC to put hardware into servers, VMs into storage” and after I read it, I couldn’t help but to juxtapose the articles with what I said earlier in my blogs, here and here.

It is very interesting to note that “EMC runs vSphere directly on the storage controllers and then uses vMotion to migrate VMs from application servers onto the storage array, ..” since the storage boxes have enough compute power to run Virtual Machines on the storage. Traditionally and widely accepted, VMs should be running on servers. Contrary to beliefs, EMC has already demonstrated this running of VMs capability on their VNX, Isilon and Symmetrix.

And soon, with EMC’s Project Lightning (announced at EMC World in May 2011), they will be introducing server side PCIe-based SSDs, ala Fusion-IO. This is different from the NetApp PAM/FlashCache PCIe-based card, which sits on their arrays, not on hosts or servers. And it is also very interesting to note that this EMC server-side PCIe Flash SSD card will become a bridge to EMC’s FAST (Fully Automated Storage Tiering) architecture, enabling it to place hot, warm and cold data strategically on different storage tiers of the applications on VMware’s VMs (now on either the server or the storage),  perhaps using vMotion as a data mover on top of the “specialized” link created by the server-side EMC PCIe card.

This also blurs the line between the servers and storage and creates a virtual architecture between servers and storage, because what used to be distinct data border of the servers is now being melded into the EMC storage array, virtually.

2 red alerts are flagging in my brain right now.

  1. The “bridge” has just linked the server back to the storage, after years of talking about networked storage. The server is ONE again with the storage. Doesn’t that look to you like a server with plenty of storage? It has come a full cycle. But more interesting and what I am eager to see is what more is this “bridge” capable of when it comes to data management. vMotion might be the first of many new “protocol” breeds to enhance data management and mobility with this “bridge”. I am salivating right now of this massive potential.
  2. What else can EMC do with the VMware API? This capability I am writing right now is made possible by EMC tweaking VMware’s API to maximize much, much more. As the VMware vStorage API is continually being enhanced, the potential is again, very massive and could change the entire landscape of cloud computing and subsequently, the entire IT landscape. This is another Pavlov’s dog moment (see figures below as part of my satirical joke on myself)


Sorry, the diagram below is not related to what my blog entry is. Just my way of describing myself right now. 😉

I am extremely impressed with what EMC is doing. A lot of smarts and thinking go into this and this is definitely signs of things to come. The server and the storage are “merging again”. Think of it as Borg assimilation in Star Trek.

Resistance is futile!

More specialized appliances at Oracle OpenWorld

I was reading the news from Oracle OpenWorld and a slew of news about specialized appliances are on the menu.

Oracle added Big Data Appliance and Oracle Exalytics Business Intelligence Machine to its previous numero uno, Exadata Database Machine. EMC, also announced its Green Plum Data Computing Appliance and also its VNX Unified Storage for Oracle.

As quoted

The EMC VNX Unified Storage for Oracle is a VNX system that has 
Oracle installed in a VMware vSphere virtual machine environment. 
The system is meant to unify all Oracle environments--database over 
Oracle Direct NFS, application servers over NFS, and testing and 
development over NFS--resulting in less disk space used and faster 
testing. EMC says this configuration was made because 50% of Oracle 
customers are virtualizing their systems today.

The VNX Unified Storage for Oracle includes EMC's Fully Automated 
Storage Tiering (FAST) technology, which migrates most frequently 
used data between a primary Fibre Channel drive and solid state drives 
and migrates less frequently used data to Serial ATA (SATA) drives and 
its FAST Cache. In an Oracle environment, FAST is well-suited to 
database applications that generate a large number of random 
inputs-outputs, that experience sudden bursts in user query activity, 
or a high number of user loads and where the entire working set can 
be contained in the solid state drive cache.

Based on testing carried out on an Oracle Real Application Clusters 
(RAC) 11g database that was configured to access the VNX7500 file 
storage over the Network File System (NFS), using the Oracle 
Direct NFS (dNFS) client, results showed an 100% improvement in 
transactions per minute (TPM), 170% improvement in IOPS, and 
a 79% decrease in response time, the company said.

As for GreenPlum, EMC quoted:

The company also is showing off the EMC Greenplum Data Computing 
Appliance(DCA) for Big Data Analytics configuration, which provides 
a new migration path to Greenplum for Oracle Data Warehouse. This 
system includes the Greenplum Data Computing Appliance, EMC's 
Global Data Warehouse, and EMC's IT Business Intelligence Grid 
infrastructure. The EMC Greenplum DCA consists of 8 to 16 segment 
servers running Red Hat Enterprise Linux. Each segment server 
contains 96 to 192 processor cores, with 384 GB to 768 GB of 
memory per segment server. The DCA includes 12 600-GB Serial 
Attached SCSI (SAS) 15K RPM drives for a total useable and 
compressed capacity of 73 TB to 144 TB. The DCA competes with 
Oracle's Exadata Database Machine.

In tests performed with this server/storage configuration and a 
15-TB Oracle Data Warehouse, the DCA processed a 99 million rows 
query in less than 28 seconds vs. seven minutes in a traditional 
Oracle environment and data loads decreased from six days to 29 

It is getting pretty obvious that specialized appliances are making waves at Oracle OpenWorld but what’s more interesting is the return of a combined and integrated environment of compute and storage as I have mentioned in my previous blog. And I forsee that these specialized appliances will be one of the building blocks of cloud computing together with general purposes platforms such as x86, JBODs and the glue to all these, virtualization, notably VMware.

The rise of the specialized appliance

Compute and storage are 2 components within the IT infrastructure which are surely converging. SAN and NAS are facing their greatest adversary yet, and could be made insignificant if the cloud and virtualization game had their way. This is giving rise to the a new breed of solution, a specialized appliance where both compute and storage are ONE. Rising from the ashes of shared storage (SAN and NAS, take note), we are beginning to see things going back to way of direct, internal storage.

There were some scuffles in the bushes about 5 years, where Sun (now Oracle) was ahead of its game. The Sun Fire X4500 (aka Thumper) was one of the strong candidates to challenge the SAN/NAS duopoly in this networked storage period. X4500 integrated both the server and the storage components together, using ZFS as a file system and volume manager to deliver a very high throughput on all the JBOD disks very efficiently. ZFS acted as the RAID, so there was no need to have specialized RAID hardware. This proved that a very high performance storage solution can be easily integrated using standard off-the-shelf infrastructure components and the x86 architecture. By combining both compute and storage together, there were hints that the industry was about to rise up to Direct-Attached Storage (DAS) again, despite its perceived weakness against SAN and NAS.

Unfortunately, the applications were not ready for DAS then. Besides ZFS, applications such as databases, emails and file servers were not ready to jump into the DAS bandwagon and watch them ride into the sunset. But the fairy tale seems to be retold again, and this time, the evidence that DAS could rise again is much stronger.

The catalyst to this disruptive force? Virtualization!

I mentioned that VMware is the silent storage killer a few blogs ago. Needless to say, that ruffled a few featheres among the readers. I have no doubt that virtualization is changing how we storage guys look at SAN and NAS. In a traditional setup, the SAN or NAS is setup to provision LUNs or mount points to the data storage for VMFS volumes in the VMware environment. It will then be the storage array to provide snapshots, replications, thin provisioning and so on.

Perhaps VMware is nit picking that managing storage arrays for VMFS volumes is difficult. From the VMware administrators view, they are right. They don’t want to know what’s going on below the VM-level. All they want is storage, any kind of storage and VMware will manage the volumes, snapshots, replication and thin  provisioning. Indeed they were already doing that since vStorage API was introduced. In the new release of VMware version 5.0, the ante has been upped even higher, making networked storage less and less significant.

If you want to know about vStorage API and stuff, below is a diagram of the integration of the various components at the VMware API level.

VMware can now use direct, internal storage look like shared storage. The Virtual Storage Appliance (VSA) does just that. VMware already has a thriving market from the community and hobbists for VMware Appliances.

The appliance market has now evolved into new infrastructure too. Using x86 architecture, off-the-shelf infrastructure components (sounds familiar?), companies such as Nutanix and Tintri are taking advantage of this booming trend to introduce specialized VMware appliances as shown in their advertisements on their respective web sites.

Here’s the Nutanix Ad:

Here’s the Tintri Ad:

Both Tintri and Nutanix are a new breed of appliances – specialized appliances for VMware.

At the same time, other applications are building these specialized appliances as well. I have mentioned Oracle Exadata many times in the past and Oracle Exadata is the perfect example an a fine-tuned, hardcore database engine to make the Oracle run at the best performance possible.

Likewise HP has announced their E5000 Messaging System for Microsoft Exchange. The E5000 is a specialized appliance optimized and well-tuned for the Microsoft Exchange Server 2010. From the words of HP,

“HP E5000 Messaging System is the industry’s first fully self-contained platform built for the next-generation of Microsoft Exchange to deliver enterprise-class messaging to businesses of all sizes. Built as a turnkey solution that can be up and running in a few hours vs. days, the HP E5000 Messaging System gives business users the experience they want most: large mailboxes, centralized archiving of mailboxes files and 24×7 access from any device. IT staffs benefit the solutions simplicity to setup, scale and manage and to meet new demands affordably. Ideal for multi-site enterprises as well as branch office and remote office environments, each HP Messaging System delivers greater simplicity and accelerates deployment with preconfigured solutions starting at 500 mailboxes up to 3000 mailboxes, while delivering large, 1 to 2.5GB mailbox sizes. Clients can grow by adding storage capacity or more appliances within the environment up from hundreds to thousands of mailboxes.”

What are the specs of this E5000 box, you say? Here you go:

And look at Row#2 in the table above … Direct, Internal Disks! Look at Row #4, Xeon CPUs! Both Compute and Storage in the same appliance!

While the HP E5000 announcement was recently, Hitachi Data Systems were already in the game early with their Unified Compute Platform and their Converged Platform for Microsoft Exchange with relatively the same idea – specialized appliances.

Perhaps the HDS solutions aren’t exactly direct, internal storage but the concept is still the same – specialized appliance. HDS Unified Compute Platform (UCP) has these components.

HDS Converged Platform for MS Exchange provides their specialized “appliance” with Reference Architectures that can support up to 68,000 Microsoft Exchange mailboxes. Here’s an architecture diagram of their “appliance”

There’s no denying that the networked storage landscape is changing. So are the computing platforms. We are already seeing the compute and storage components being integrated together, tighter than ever. The wave is rising for specialized appliances and it can only get more intense from now on.

No wonder HP’s Converged Infrastructure vision is betting on x86 architecture, simple storage platforms with SAS/SATA disks and Virtualization. Other vendors are doing the same as well – Cisco, NetApp and VMware with their FlexPod solution and EMC with their VBlocks of VMware, Cisco and EMC Storage.

Hail to the Rise of the Specialized Appliance!

VMware – the silent storage killer

When VMware 5.0 was launched last month, I heard the feature called Virtual Storage Appliance (VSA) was finally out and is now being offered as an SMB/SME “storage” solution. In my mind, alarm bells were ringing because in its own stealthy manner, VMware had just become a storage player.

What VMware is offering is “Hey! If you don’t have money to buy your enterprise storage array, don’t worry. Make your own shared storage with our very own VMware VSA“. VSA utilizes the internal disks of the ESX/ESXi host as its shared storage.

VSA is nothing new. For years, LeftHand Networks had one for its engineers to do demo and show the functionality of their solution. EMC had it too, and recently I found out that NetApp has its own VSA, but only resell through its partner, Fujitsu. I am not 100% sure about the NetApp thing and I need a NetApp guy to verify this.

Smaller players, but not insignificant, such as Nutanix, Nexenta and Tintri are already offering their own versions and implementation of VSA to their customers, each with its own uniqueness and differences. With the release of the VMware VSA into the open, we shall see all the big storage players offering their VSAs to VMware, like natives offering sacrifices to VMware God. Or perhaps, it has already begun. It is ala-Nexus 1000v all over again.

VMware has become a huge juggernaut and it is merely using its advantage to consolidate the storage component under its control. When VMware version 4.0 came out, vStorage API was introduced along with VAAI (vStorage API for Array Integration). VAAI was created to enhance the storage experience by offloading specific storage operations to the native features of that supported storage platform. That’s all I know about VAAI at this moment, but with this feature, the storage array is tightly integrating its platform to VMware, or should I say … quietly ensnared by VMware tentacles of doom! (Evil laugh in the background! Mua ha ha ha ….!)

In the recently past VMworld, this storage story is slowly being unfurled even more to the world. VASA (vStorage API for Storage Awareness) was recently announced and EMC’s COO Pat Gelsinger spoke about the tighter integration (that word again!) that blurs the administration domain of the VMware admin and the storage admin. Below is a video of Pat Gelsinger talking about VASA below (this is long 55 minute video – Click only if you have the time).

Mind you, the entire vStorage API is still evolving as VMware 5.0 rolls out but here’s the thing. VMware has come out and say that the storage world about LUNs, RAID groups and mount points are a level below what the VMware admin should be concerned about. VMware admins handles their storage at the VM level or as VMDK and therefore, anything below it is of little significance to them. Again, you can see that VMware is using its muscle to say “If you guys want to play, you have to play by my rules“.

So, some new announcements came out from VMworld for storage such as Capacity Pools, I/O Multiplexer, and Storage DRS (Storage Distributed Resource Management) and also an enhanced version (probably more storage resilient) SRM (Site Recovery Manager). All these are being managed at a level above the traditional storage admin level and VMware has said that the VMware admin would be able to carve out a VM volume with its own set of default storage properties, defined snapshot retentions, replication and perhaps even compression and deduplication. But all these will be happening at the VM volume or VMDK level, not a level below that.

Details are still sketchy at this point in time and we probably won’t see these GA until probably VMware version 6.0. But the inertia has been rocked quietly and the VMware storage momentum will gain strength as time passes by. We could see that VMware would just need JBOD (just a bunch of disks) because it has its own enterprise storage features through its vStorage APIs or its future storage specifications. We have seen it happening in VSA with VMware offering its own storage.

From the similar news, what surprised me was what was quoted as shown below.

The presenters said VMware developed the APIs with EMC, NetApp, Dell,
IBM and Hewlett-Packard,but they began the session with a disclaimer
that none of those vendors has committed to support the APIs in
their arrays.

Why the hell would EMC, NetApp, Dell, IBM and HP do something like that?!! Don’t they know that this could contribute to their insignificance in the future?

I am still perplexed but as the whole thing is still evolving, VMware seems to be only obvious winner here.

NFS deserves more credit from guys doing virtualization

I was at the RedHat Forum last week when I chanced upon a conversation between an attendee and one of the ECS engineers. The conversation went like this

Attendee: Is the RHEV running on SAN or NAS?

ECS Engineer: Oh, for this demo, it is running NFS but in production, you should run iSCSI or Fibre Channel. NFS is only for labs only, not good for production.

Attendee: I see … (and he went off)

I was standing next to them munching my mini-pizza and in my mind, “Oh, come on, NFS is better than that!”

NAS has always played a smaller brother to SAN but usually for the wrong reasons. Perhaps it is the perception that NAS is low-end and not good enough for high-end production systems. However, this is very wrong because NAS has been growing at a faster rate than Fibre Channel, and at the same time Fibre Channel growth has been tapering and possibly on the wane. And I have always said that NAS is a better suited protocol when it comes to unstructured data and files because the NAS protocol is the new storage networking currency of Internet storage and the Cloud (this could change very soon with the REST protocol, but that’s another story). Where else can you find a protocol where sharing is key. iSCSI, even though it has been growing at a faster pace in production storage, cannot be shared easily because it is block-based.

Now back to NFS. NFS version 3 has been around for more than 15 years and has taken its share of bad raps. I agree that this protocol is still very much in the landscape of most NFS installations. But NFS version 4 is changing all that taking on the better parts of the CIFS protocol, notably the equivalent of opportunistic locking or oplocks. In addition to that it has greatly enhanced its security, incorporating Kerberos-type of authentication. As for performance, NFS v4 added in a compounded in a COMPOUND operations for aggregating operations into a single request.

Today, most virtualization solutions from VMware and RedHat works with NFS natively. Note that the Windows CIFS protocol is not supported, only NFS.

This blog entry is not stating that NFS is better than iSCSI or FC but to give NFS credit where credit is due. NFS is not inferior to these block-based protocols. In fact, there are situations where NFS is better, like for instance, expanding the NFS-based datastore on the fly in a VMware implementation. I will use several performance related examples since performance is often used as a yardstick when these protocols are compared.

In an experiment conducted by VMware based on a version 4.0, with all things being equal, below is a series of graphs that compares these 3 protocols (NFS, iSCSI and FC). Note the comparison between NFS and iSCSI rather than FC because NFS and iSCSI run on Gigabit Ethernet, whereas FC is on a different networking platform (hey, if you got the money, go ahead and buy FC!)

Based a one virtual machine (VM), the Read throughput statistics (higher is better) are:

The red circle shows that NFS is up there with iSCSI in terms of read throughput from 4K blocks to 512K blocks. As for write throughput for 1 VM, the graph is shown below:

Even though NFS suffers in write throughput in the smaller blocks less than 16KB, NFS performance write throughput improves over iSCSI when between 16K and 32K range and is equal when it is in 64K, 128K and 512K block tests.

The 2 graphs above are of a single VM. But in most real production environment, a single ESX host will run multiple VMs and here is the throughput graph for multiple VMs.

Again, you can see that in a multiple VMs environment, NFS and iSCSI are equal in throughput, dispelling the notion that NFS is not as good in performance as iSCSI.

Oh, you might say that this is just VMs without any OSes or any applications running in these VMs. Next, I want to share with you another performance testing conducted by VMware for an Microsoft Exchange environment.

The next statistics are produced from an Exchange Load Generator (popularly known as LoadGen) to simulate the load of 16,000 Exchange users running in 8 VMs. With all things being equal again, you will be surprised after you see these graphs.

The graph above shows the average send mail latency of the 3 protocols (lower is better). On the average, NFS has lower latency than iSCSI, better than what most people might think. Another graph shows the 95th percentile of send mail latency below:

Again, you can see that the NFS’s latency is lower than iSCSI. Interesting isn’t it?

What about IOPS then? In another test with an 8-hour DoubleHeavy LoadGen simulator, the IOPS graphs for all 3 protocols are shown below:

In the graph above (higher is better), NFS performed reasonably well compared to the other 2 block-based protocols, and even outperforming iSCSI in this 8-hour load testing. Surprising huh?

As I have shown, NFS is not inferior compared to the block-based protocols such as iSCSI. In fact, VMware in version 4.1 has improved all 3 storage protocols significantly as mentioned in the VMware paper. The following are quoted in the paper for NFS and iSCSI.

  1. Using storage microbenchmarks, we observe that vSphere 4.1 NFS shows improvements in the range of 12–40% for Reads,and improvements in the range of 32–124% for Writes, over 10GbE.
  2. Using storage microbenchmarks, we observe that vSphere 4.1 Software iSCSI shows improvements in the range of 6–23% for Reads, and improvements in the range of 8–19% for Writes, over 10GbE

The performance improvement for NFS is significant when the network infrastructure was 10GbE. The percentage jump between 32-124%! That’s a whopping figure compared to iSCSI which ranged from 8-19%. Since both protocols are neck-to-neck in version 4.0, NFS seems to be taking a bigger lead in version 4.1. With the release of VMware version 5.0 a few weeks ago, we shall know the performance of both NFS and iSCSI soon.

To be fair, NFS does take a higher CPU performance hit compared to iSCSI as the graph below shows:

Also note that the load testing are based on NFS version 3. If version 4 was used, I am sure the performance statistics above will take a whole new plateau.

Therefore, NFS isn’t inferior at all compared to iSCSI, even in a 10GbE environment. We just got to know the facts instead of brushing off NFS.