Fear

Back when I used to teach the “Storage 101″ session at Storage Decisions, I was consistently amazed to find little awareness of enterprise NAS systems. People complained about LUNs and Fibre Channel but when I suggested using NFS or SMB their heads almost exploded. “We would never use that for application storage,” they shouted. “File servers are for home directories, not data center stuff!” Clearly, NAS faces an uphill battle.

In a recent piece I wrote, I referred to what I consider to be the prime best practice: Use the right tool for the job. It’s a simple statement, and one that resonates beyond IT and the technology world. But it can be devilishly difficult to see what the right tool is sometimes. Why not use NAS for virtual machine storage? NetApp has been beating that drum for years, yet NAS has a very small footprint in VMware. How about databases on NFS? Exchange over SMB? Block storage has a massive lead over NAS in all of these areas.

Rear this “best practices” piece, Use Process Solutions For Process Problems, Technical Solutions For Technical Ones

IT folks seem downright fearful of file-level storage protocols. Has NFS really burned them that badly over the decades? Can SMB/CIFS really be as bad as they think?

Loathing

I wonder if this terror has more to do with the products people have used than the fundamental concept of file services. Many NAS servers (and clients) are barely functional. Sadly, NFS and SMB are easy to get 80% right, but the 20% corner case interaction takes decades to overcome. My daily storage consulting work exposes me to a myriad of NAS configurations, and few of the multi-platform combinations end well.

Note: Although it has long been known by a variety of names, the Windows NAS protocol is currently called Server Message Block or SMB. Common Internet File System (CIFS) was a failed mid-1990′s attempt by Microsoft to make this protocol standard on the Internet.

Consider the Mac. Apple added an SMB client to OS X in 2001 but, despite many updates, it is far from reliable. Mac users in general loathe connecting to Windows file servers, and business users have located numerous bugs in the handling of Mac-specific file types. It’s bad enough that one company, GroupLogic, created an entire AFP server for Windows just to solve these tricky issues.

This situation often happens in reverse, too. Windows admins are justifiably cautious when deploying non-Windows SMB servers, whether software (Samba, Novell, etc) or system (NetApp, Celerra, BlueArc, etc). As a very early NetApp user, I watched their CIFS/SMB server evolve over a decade and a half into a fairly robust solution, but the early years were downright painful.

Lest you throw rocks at Redmond, know that SMB is not alone with functionality problems. The interoperability of NFS servers and clients is a bit better thanks to open(ish) standards and open source implementations, but its reputation is just as bad. And Apple’s proprietary AFP protocol is downright notorious.

I’ve been there myself many times. I tried to set up a home server based on open source software (Linux, FreeBSD, Samba, Netatalk, etc) but rejected it outright after many frustrating years. Today I use a Mac Mini for file sharing in OS X and serving iTunes music and movies (goodbye, Firefly!) And years of fighting with Samba in enterprise environments taught me two things: It’s possible to get it running well with Windows clients but it’s astonishingly easy to get it wrong.

Enterprise NAS?

We all know that interoperability is devilishly difficult. I don’t envy the NetApp and EMC engineers that have to tweak and tune their server for every possible client, bugs and all. And I am impressed that, after probably millions of man-hours of work, they were able to come up with something stable for a subset of use cases. But this just makes me even more cautious about third-party NAS servers.

I talk to storage vendors all the time, and many of their new products support NFS and SMB. But my internal alarms start going off when I hear about these products. There are two simple reasons for this:

1. As mentioned above, NAS is rare in primary data center applications. It may be common for user files (euphemistically called “unstructured data”) and certain distributed applications (simulation, rendering, etc), but most use cases still call for block SCSI (FC/iSCSI) storage.
2. As further mentioned, getting NAS right takes a massive amount of effort. New and small vendors tend to slap Samba on their (Linux-based) box and call it a day. This is very, very far from being sufficient for enterprise use.

This is why I usually ignore NAS functionality in storage systems except for long-tenured and deep-pocketed vendors. Although the world is turning to “Unified Storage” and multi-protocol support, I’m focusing primarily on block (SCSI) and cloud (REST) capability because the former has proven somewhat easier than NAS to get working and the latter is both simple and “green field” with no legacy concerns.

© sfoskett for Stephen Foskett, Pack Rat, 2010. | Why Do I Ignore NAS?
This post was categorized as Apple, Computer History, Enterprise storage, Gestalt IT, Terabyte home, Virtual Storage. Each of my categories has its own feed if you'd like to filter out or focus on posts like this.

But cloud services are different. Seriously! Cloud services don’t need standards because:

1. Cloud services are still rapidly evolving – No one knows how they will look in a year, let alone a decade, and a premature standard will be worthless. Similarly, it’s not at all clear what use cases will eventually win out, and usage should drive interfaces, not the other way around.
2. Cloud services are many and varied – It’s incredibly hard to come up with a reasonably-complete standard programming API or management platform when each vendor’s offering is radically different. Standards must follow the 80/20 rule, but today’s cloud offerings are only about 20% similar.
3. (Real) cloud systems are open already – The whole point of the public cloud is to leverage existing open standards for access (IP/HTTP) and any worthwhile service already has a freely-usable REST-like API. Cloud services are engineered to be programmable and open, so the only lock-in is in how you use the cloud.

We can’t even agree on terminology at this point. Is data storage as a service DaaS (as SNIA says) or STaaS (as NetApp says)? How do you define public, private, and hybrid cloud? And what is cloud anyway? Cloud computing is not a war, it’s a fantastically exciting race to deliver value!

Open for Business

I’d like to return for a moment to that last point: The key element I’ve seen in most interesting cloudy products is programmability. Service providers publish API documents outlining the inputs, processing, and outputs for their systems and developers and end users create applications that leverage these. The best of these APIs use the concept of REST, delivering services through extremely simple and self-contained HTTP calls. This barely even rises to the level of software coding (and thus isn’t a true API) and is the hallmark of the cloud.

These systems are wide open: You can explore their interfaces, discovering new ways to use the them that were never intended. The same process accompanies all Internet systems, from RSS and Atom to Yahoo Finance. Just as one can rapidly migrate from Yahoo to Google by substituting a few URLs and parameters, so too can one move between cloud platforms.

Note that certain cloud systems lend themselves more to this kind of mobility. Once cannot move virtual machines from Amazon EC2 to Rackspace or Terremark because the underlying hypervisor technology is different. But even here companies like RightScale are stepping in to enable mobility.

When it comes to cloud storage services, the major players’ interfaces are open enough that migrating data in and out is simply a matter of performance: Read from this one, write to that one, and wait until the process is done. I am not a programmer and yet I was able to port an application from S3 to Nirvanix in just a few hours using only the respective API documentation. Interfaces like CloudLoop can also be leveraged to ease the movement of data.

Standards When?

Cloud services will eventually settle down and be standardized. I expect a workable cross-platform API for RESTful cloud storage within 24 months, for example. And one expects that the management of cloud compute instances will pass through a consistent and stable interface in that same timeframe. But these will develop as a natural part of the evolution of the systems themselves, not through some artificial “build it and they will come” standardization process.

There is nothing wrong with big companies sending their representatives to SNIA and DMTF meetings to talk about standardization. In fact, this is a great way to discuss ideas and begin to orient the industry. But the time for standards has not yet come, and users of cloud services have no need to wait for them. In fact, waiting for a standard will just prolong the maturation of cloud services, since real-world applications are the external pressure that forces evolutionary selection. Amazon would never have created their virtual private cloud (VPC) capability without customer input, and they will never perfect this capability if they rely only on pundits, bloggers, and product marketers.

Even when standards do appear, they will not eliminate per-solution APIs. Cloud service providers will continue to explore new concepts, and these will appear first in “proprietary” interfaces. Perhaps they will use entirely unique calls, or perhaps they will leverage reserved or unassigned sections of the standard, but innovation will continue. Witness the radical changes in HTML versions to date, the additions to CSS, and the wide world of browser plugins.

So we don’t need cloud standards yet. They will come, whether artificially pushed by committees or evolving through use, but only useful standards will survive. Isn’t that just how it should be?

Note: I am employed by Nirvanix, a cloud managed storage service provider, providing independent cloud strategy advice as Director of Consulting. Although this article was not created for my employer and is not intended to reflect their views, my perceptions are obviously colored by my daily work.

© sfoskett for Stephen Foskett, Pack Rat, 2009. | We Don’t Need Cloud Standards (Yet)
This post was categorized as Computer History, Enterprise storage, Gestalt IT, Virtual Storage. Each of my categories has its own feed if you'd like to filter out or focus on posts like this.

Great! But I thought the new era for IT was a cloud with choice, mobility, and application support, as trumpeted by EMC’s VMware subsidiary! Wasn’t Cloud vServices from VDC-OS supposed to be the prototype cloud strategy for the datacenter?

What we have here is a simple clash of marketing amusingly taking place at (nearly) the same company. VMware figured out how to extend their server virtualization products outside the confines of the data center, and laid that technology out as a strategy with the trendy “cloud” name. Meanwhile, mother EMC is working on next-generation content storage software and decides to roll that out as a strategy and also jumps on the “cloud” meme. What’s an IT manager to do?

Defining Atmos

As predicted, EMC’s Atmos (code-name Maui) is a distributed software layer to handle the storage and management of data objects across geographically-dispersed storage devices. EMC’s Chuck Hollis demonstrates Atmos with a simple, practical example, perhaps making it sound too much like Akamai but generally getting the point across. You have a data object, write it to Atmos through REST/SOAP or CIFS/NFS, assign some metadata, and the software takes care of data placement for you. It’ll add local copies, replicate for availability and performance, compress or deduplicate, manage versions, and all sorts of goodies (if you ask it to).

But EMC already has a capable object storage platform, the Centera. We’ve just got used to the content-addressable storage (CAS) label for object storage (even though this name misses the point of object storage, in my opinion) and now EMC wants us to learn a new label for a somewhat-similar device? Steve Todd, EMC’s object guy extraordinaire, lays it out:

SAN Value = Centralized, secure multi-tenancy for blocks.

NAS Value = Centralized, secure multi-tenancy for files.

CAS Value = Centralized, secure multi-tenancy for objects (content + metadata).

COS Value = Globalized, secure multi-tenancy for content with rich policies.

Ok, so the defining capabilities of Atmos are its global scale and rich policies. And the fact that “objects” has become “content”, presumably since Atmos can handle traditional NAS (CIFS/NFS) chores as well.

Prayers Answered?

It sounds like EMC is answering my prayers for a storage revolution, delivering a highly-capable object storage platform that transcends the old limits of blocks, directories, and files. Steve Todd points out that Atmos handles five policy categories out of the box:

• Replication
• Compression
• Spin-down
• Object de-dup
• Versioning

So we write some data to Atmos, using either traditional NAS or webby dubby protocols like SOAP, and can then apply policies in any of these five categories to that data. One can also extend the Atmos to accept other policies, but the absence (out of the box) of concepts like encryption, secure deletion, retention, and access control are surprising.

I am quite puzzled about how practical these policy capabilities will be in the real world. How exactly would an application say “I want you to compress that file I wrote over NFS just now?” Hitachi’s HCAP platform, for example, also has policy capabilities and a NAS front end, and although archiving applications can communicate their policy needs, I don’t see lots of current general-purpose applications using it.

Strategic Storage?

This brings me to my puzzlement: The default Atmos policies are all general-purpose, production computing ideas, not the special-purpose, archiving and retention needs served by Centera, HCAP, and the rest. So the Atmos is clearly intended to be a production data storage system, not an archiving system to compete with Centera.

Since mainstream business applications currently don’t have any capability to specify policies like these when writing files, and since NAS protocols lack any means to communicate them even if the apps want to, we can conclude that EMC expects that Atmos users will write special applications to take advantage of it.

EMC certainly doesn’t expect that the NAS-capable Atmos will simply replace today’s distributed NAS solutions. NAS is a sideshow for Atmos. The real action will be in the REST/SOAP webby dubby applications that will be written with the platform in mind and will take full advantage of these capabilities.

If this is true, and I and others suspect that it is, then Atmos really isn’t a game-changing platform unless you change your game. If you write new applications to store data with SOAP, Atmos is a nice in-house alternative to Amazon S3 or Nirvanix, and offers a very compelling set of data management capabilities. And if you want to set up shop to compete with those service providers, Atmos is a dream come true with built-in multi-tenancy.

Datacenter Strategy

So EMC alone has two seemingly competitive datacenter strategies. And then there’s Microsoft, which announced its Azure cloud platform recently, and Amazon and the other cloud providers.

So let’s say you’re a CIO for a large corporation. Which of the following strategies is more compelling:

1. Use VMware VDC-OS to add capabilities and Cloud vServices extend your current virtual infrastructure geographically
2. Recompile and tweak your Windows applications to leverage Microsoft Azure
3. Develop new applications to take advantage of the impressive storage capabilities of an in-house EMC Atmos system
4. Point your new applications at a third-party cloud provider like Amazon or Nirvanix

IT people are practical. Although we love new technology, we tend to be cautious. We also hate massive software development efforts, and only sanction them when they’re absolutely necessary. Given these personality traits, I’d say VDC-OS and perhaps Cloud vServices still stands out as the most likely and practical scenario for the majority of applications and businesses.

This is not to say that EMC Atmos will be a flop. I’m impressed by the technology, and expect that Atmos will find buyers, just as Centera did. And Atmos might even replace Centera once EMC adds retention policies to it and scales it down as well as up and out. But Atmos will not redefine the datacenter. We’re stuck with blocks and files, and VMware’s practical strategy is a winner in that world.

Update: Marc Farley compares Atmos to WAFS, with ominous implications, and echos my recent question on what is and is not innovative.

Update 2: Chuck Hollis, Storagezilla, and Len Devanna have all come right out and said that this is only intended for certain customers with massive distributed storage needs, and is not intended as a new datacenter strategy. Even the “cloudfella” says “ciao”:

Update 3: More great information, including a reply regarding VDC-OS and Atmos from the one and only Chad Sakac, more great detail about the inner workings of Atmos from Steve Todd, and even more info from Dave Graham. Finally, although I think that Cloudfellas video is cute, I wouldn’t categorize it as viral. But those Mozy ads are awesome!

See my posts on Gestalt IT for similar enterprise IT infrastructure commentary

© sfoskett for Stephen Foskett, Pack Rat, 2008. | EMC Atmos Versus VMware VDC-OS: Will The Real Cloud Strategy Please Stand Up?
This post was categorized as Enterprise storage, Virtual Storage. Each of my categories has its own feed if you'd like to filter out or focus on posts like this.