Category: smb

SMB3 – These Questions Rock!

John Kim Leave a comment
Earlier this month, the SNIA Ethernet Storage Forum hosted a live webcast on Server Message Block (SMB), “Rockin’ and Rollin’ with SMB3.” Presenting was Ned Pyle, Microsoft SMB Program Manager. If you missed the live event, I encourage you to watch it on-demand. We had a lot of questions from the big audience this event drew, so as promised, here are answers to them all. Q. Other than that audit setup, is there a way to determine, via the OS, which SMB version is in use? Read More

Rock n’ Roll with SMB3

AlexMcDonald

Server Message Block (SMB) is the core file-transfer protocol of Windows, MacOS and Samba, and has become widely deployed. It’s ubiquitous – a 30-year-old family of network code.

However, the latest iteration of SMB3 is almost unrecognizable when compared to versions only a few years old. That’s why the SNIA Ethernet Storage Forum (ESF) has invited Microsoft’s Ned Pyle, program manager of the SMB protocol, to speak at our live webcast, “Rockin’ and Rollin’ with SMB3.”

Extensive reengineering has led to advanced capabilities that include multichannel, transparent failover, scale out, and encryption. SMB Direct makes use of RDMA networking, creates block transport system and provides reliable transport to zetabytes of unstructured data, worldwide.

SMB3 forms the basis of hyperconverged and scale-out systems for virtualization and SQL Server. It is available for a variety of hardware devices, from printers, network-attached storage appliances, to Storage Area Networks. It is often the most prevalent protocol on a network, with high-performance data transfers as well as efficient end-user access over wide-area connections. Register now for the live event on April 5th to hear:

  • Brief background on SMB
  • An overview of the SMB 3.x family, first released with Windows 8, Windows Server 2012, MacOS 10.10, Samba 4.1, and Linux CIFS 3.12
  • What changed in SMB 3.1.1
  • Understanding SMB security, scenarios, and workloads
  • The deprecation and removal of the legacy SMB1 protocol
  • How SMB3 supports hyperconverged and scale-out storage

This is a unique opportunity to “rock out” with an SMB3 expert on the front lines at Microsoft. We hope to see you on April 5th.

Common Questions on Clustered File Systems

John Kim

More than 350 people have already seen our SNIA Ethernet Storage Forum (ESF) webcast “Clustered File Systems: No Limits.” Our presenters, James Coomer and Jerry Lotto, did a great job explaining what clustered file systems are, key considerations, choices and performance. As we expected, there were plenty of questions, so as promised, here are answers to them all.

Q: Parallel NFS (pNFS) has been in development/standard effort for a long time, and I believe pNFS is not in the Linux kernel it appears pNFS is yet to be prime time.

A: pNFS has been in Linux for over a decade! Clients and server are widely available, and you should look at the SNIA White Paper “An Updated Overview of NFSv4; NFSv4.0, NFSv4.1, pNFS, and NFSv4.2” for more information on the current state of play.

Q: Why the emphasis on parallel I/O? Any single storage server can feed results at link capacity, so you do not need multiple storage servers to feed a client at full speed. Isn’t the more critical issue the bottleneck on access to metadata for a single directory or file? Federated NAS bottlenecks updates for each directory behind a single master server?

A: Any one storage server can usually saturate one client, but often there are multiple hungry clients making requests simultaneously. Using parallel I/O allows multiple servers to feed multiple high-bandwidth clients across a narrow or wide set of data. This smooths out the I/O load on the servers in a near-perfect manner regardless of the number of clients performing I/O. It is absolutely true that metadata serving can become a bottleneck, so parallel file systems use cached and/or distributed metadata to overcome this and again, every client takes part in that interaction and shares some responsibility for managing communicating metadata updates.

Q: Can any application access parallel file system (i.e. through an agent in the driver level)? Or does it require specific code within the application?

A: Native access to a parallel file system requires a specific client or agent in the host, but many parallel file systems allow any client to access the data through a NAS protocol gateway. No changes are needed to applications to use a parallel file system – These parallel file systems are mounted as a POSIX compliant file system and therefore adhere to basically the same standards as an NFS mount for example.

Q: Are parallel file system clients compatible with scale-out NAS servers?

A: Nearly all scale-out NAS servers speak a standard NAS protocol like NFS or SMB. Clients running a parallel file system client can also access NAS via these standard protocols. Exceptions to this may possibly (but none that we know of) occur for scale-out NAS servers that support a modified NFS/SMB protocol or a custom NAS client which might conceivably conflict with the parallel file system client when installed on an OS.

Q: Of course I am biased, but I am fond of the AFS (Andrew File System) Family of File Systems.   There is OpenAFS, but there is also what we are doing at AuriStor extending beyond the core AFS global namespace model (security functionality, and performance)

A: AFS is another distributed file system which supports large scale deployments, native clients for many platforms, and strong security features. It also uses local caching of files to improve performance. It uses a weakly consistent file locking system so multiple clients can access the same file simultaneously but they cannot both update the same file at the same time. OpenAFS is an open-source implementation of AFS. Auristor (formerly Your File System, Inc.) is a startup providing a commercial parallel file system that is compatible with AFS.

Q: I am more familiar with Veritas Cluster File System, could you please do a quick compare with Lustre or GPFS?

A: The Veritas Cluster File System (formerly VxCFS, now part of Veritas InfoScale) is a distributed file system that runs on Linux and popular flavors of Unix. It supports up to 64 nodes and allows multiple nodes to share the same back-end storage hardware. Comparing it to Lustre and GPFS is beyond the scope of this webinar, but in basic terms, parallel file systems can offer far greater scalability and bandwidth for example, through the use of optimized RDMA clients for high performance networks.

Q: Why do file apps need shared access to data, but block apps do not?

A: Traditionally block storage did not offer shared access to data (except when used as shared back-end storage for a clustered file system), while apps that needed shared access to data usually chose to use a NAS protocol such as SMB or NFS. So in many cases file-based apps use file sharing protocols because they need shared access to data from multiple clients. (In other cases file-based applications do not require sharing but the storage administrators believe it’s easier to manage or less expensive than networked block storage.)

Q: Do Lustre and GPFS have SMB Direct support?

A: Not today. SMB Direct is an option to use RDMA and multi-channel with the SMB 3 protocol. Both Lustre and GPFS support the ability to export a file system via NFS or SMB, but generally they do not support SMB Direct yet. Both Lustre and GPFS support RDMA access through their clients.

How to the clients avoid doing simultaneous writes to the same file?

A: Some parallel file systems allow this by letting different clients write to different parts of the same file. Others do not allow this. In either case, distributed file locking is used to prevent two clients from writing simultaneously to the same part of a file (or to the same file if it’s not allowed).

Q: How can you say that the application “does not have to worry about” how the clustered file system serializes writes? Doesn’t this require continuous end-to-end connectivity?

A: When the application writes data it generally writes to a POSIX-compliant file system and does not need to worry about how the parallel file system serializes, distributes, or protects the data because this is virtualized (managed) by the file system. It usually does require continuous end-to-end connectivity from the clients to the servers, though in some cases caching could allow for brief gaps in connectivity and in some systems not every client needs to have network connectivity to every server. There are multiple mechanisms within parallel file systems to manage the various cases of clients/servers disappearing from the network, temporarily or permanently (whilst for example holding a lock).

Q: How does a parallel file system handle the sequences of write on a same file? Just append one by one? What if a client modified a line?

A: This is the biggest challenge for and reason to use a parallel file system.  Beneath the covers, coherency is maintained by Spectrum Scale using a token management server process which issues locks for object requests.  Similar functionality is implemented in Lustre using a distributed lock manager.  These objects are most commonly blocks within files rather than entire files, but this is application controlled.  The end result is a POSIX-compliant interface that scales to thousands of clients.

Q: What does FPO stand for?

A: File Placement Optimizer – a shared-nothing architecture and licensing model for IBM Spectrum Scale (aka GPFS). Learn more here.

Q: Is there a concept in parallel file systems for “auto-tuning” yet? Seems like the early days of SAN management and tuning…

A: Default tuning values are optimized for general purpose workloads, but the whole purpose of tuning parameters is to adjust away from those defaults to optimize the file system for a particular application workload or fil esystem architecture.  Both IBM and OpenSFS with the support of Intel have published extensive documentation on best practices for optimization and tuning for either file system.  We are not aware of any work on “automating” that process but there has been recent work (e.g. in spectrum scale) to simplify the tuning process.

Q: Which is better as interconnect between disk and servers, shared access or share-nothing?

A: The use of shared access in the interconnect between disks and servers is limited to providing HA functionality in Lustre or Spectrum Scale, the ability to service I/O requests to a storage device if the server which has primary responsibility for that device is not available.  This usually involves multiple server-attached external storage which can add cost to building the file system.  The alternative approach to HA is to replicate blocks of data to different disks on different servers, cutting back on the usable capacity of the file system.  If HA is not a requirement, a share-nothing architecture will generally involve less hardware and therefore be less expensive to build.

If you have more questions, please comment on this blog. And I encourage you to check out the SNIA ESF webcast library for educational, vendor-neutral content on Ethernet networked storage topics

SNIA Tutorials Highlight Industry Track at USENIX FAST ’16

khauser Leave a comment

by Marty Foltyn

SNIA is pleased to present seven of their series of SNIA Tutorials at the 14th USENIX conference on File and Storage Technologies (USENIX FAST) on February 24, 2016 in Santa Clara, CA.  fast16_button_180_0

SNIA Tutorials are educational materials developed by vendors, training companies, analysts, consultants, and end-users in the storage and information technology industry. SNIA tutorials are presented and used throughout the world at SNIA events and international conferences.

Utilizing VDBench to Perform IDC AFA Testing will be presented by Michael Ault, Oracle Guru, IBM, Inc. This SNIA Tutorial provides procedures, scripts, and examples to perform the IDC test framework utilizing the free tool VDBench on AFAs to provide a common set of results for comparison of multiple AFAs suitability for cloud or other network based storage.

Practical Online Cache Analysis and Optimization will be presented by Carl Waldspurger, Research and Development, CloudPhysics, Inc., and Irfan Ahmad, CTO, CloudPhysics, Inc.  After reviewing the history and evolution of MRC algorithms, this SNIA Tutorial examines new opportunities afforded by MRCs to capture valuable information about locality that can be leveraged to guide efficient cache sizing, allocation, and partitioning in order to support diverse goals such as improving performance, isolation, and quality of service.

SMB Remote File Protocol (Including SMB 3.x) will be presented by Tom Talpey, Architect, Microsoft.  This SNIA Tutorial begins by describing the history and basic architecture of the SMB protocol and its operations. The second part of the tutorial covers the various versions of the SMB protocol, with details of improvements over time. The final part covers the latest changes in SMB3, and the resources available in support of its development by industry.

Object Drives: A New Architectural Partitioning will be presented by Mark Carlson, Principal Engineer, Industry Standards, Toshiba.  This SNIA Tutorial discusses the current state and future prospects for object drives. Use cases and requirements will be examined and best practices will be described.

Fog Computing and Its Ecosystem will be presented by Ramin Elahi, Adjunct Faculty, UC Santa Cruz Silicon Valley.  This SNIA Tutorial introduces and describes Fog Computing and discusses how it supports emerging Internet of Everything (IoE) applications that demand real-time/predictable latency (industrial automation, transportation, networks of sensors and actuators).

Privacy vs. Data Protection: The Impact of EU Data Protection Legislation will be presented by Thomas Rivera, Senior Technical Associate, HDS.  This SNIA Tutorial explores the new EU data protection legislation and highlights the elements that could have significant impacts on data handling practices.

Converged Storage Technology will be presented by Liang Ming, Research Engineer, Development and Research, Distributed Storage Field, Huawei.  This SNIA Tutorial discusses the concept of key-value storage, next generation key-value converged storage solutions, and what has been done to promote the key-value standard.

Get Your Registration Discount
As a friend of SNIA, we are able to offer you a $75 discount on registration for the technical sessions. Use code75FAST15SNIA during registration to receive your discount.

FAST ’16 Program
FAST ’16 will kick off with their Keynote Address given by Eric Brewer, VP Infrastructure at Google, on “Spinning Disks and Their Cloudy Future”. In addition to the SNIA Industry Track, the 3-day technical sessions program also includes 27 refereed paper presentations.

The full program is available here: https://www.usenix.org/conference/fast16/glance

 

A Deep Dive into the SNIA Storage Developer Conference – The File Systems Track

khauser Leave a comment

SNIA Storage Developer Conference (SDC) 2015 is two weeks away, and the SNIA Technical Council is finalizing a strong, comprehensive agenda of speakers and sessions. Wherever your interests lie, you’re sure to find experts and topics that will expand your knowledge and fuel your professional development!SDC15_WebHeader3_999x188

For the next two weeks, SNIA on Storage will highlight exciting interest areas in the 2015 agenda. If you have not registered, you need to! Visit www.storagedeveloper.org to see the four day overview and sign up.

Year after year, the File Systems Track at SDC provides in depth information on the latest technologies, and 2015 is no exception. The track kicks off with Vinod Eswaraprasad, Software Architect, Wipro, on Creating Plugin Modules for OpenStack Manila Services. He’ll discuss his work on integrating a multi-protocol NAS storage device to the OpenStack Manila service, looking at the architecture principle behind the scalability and modularity of Manila services, and the analysis of interface extensions required to integrate a typical NAS head.

Ankit Agrawal and Sachin Goswami of TCS will discuss How to Enable a Reliable and Economic Cloud Storage Solution by Integrating SSD with LTFS. They will share views on how to integrate SSD as a cache with a LTFS tape system to transparently deliver the best benefits for Object Base storage, and talk about the potential challenges in their approach and best practices that can be adopted to overcome these challenges.

Jakob Homan, Distributed Systems Engineer, Microsoft, will present Apache HDFS: Latest Developments and Trends. He’ll discuss the new features of HDFS, which has rapidly developed to meet the needs of enterprise and cloud customers, and take a look at HDFS at implementations and how they address previous shortcomings of HDFS.

James Cain, Principal Software Architect, Quantel Limited, will discuss a Pausable File System, using his own implementation of an SMB3 server (running in user mode on Windows) to demonstrate the effects of marking messages as asynchronously handled and then delaying responses in order to build up a complete understanding of the semantics offered by a pausable file system.

Ulrich Fuchs, Service Manager, CERN, will talk about Storage Solutions for Tomorrow’s Physics Projects, suggesting possible architectures for tomorrow’s storage implementations in this field, and showing results of first performance tests done on various solutions (Lustre, NFS, Block Object storage, GPFS ..) for typical application access patterns.

Neal Christiansen, Principal Development Lead, Microsoft, will present Support for New Storage Technologies by the Windows Operating System, describing the changes being made to the Windows OS, its file systems, and storage stack in response to new evolving storage technologies.

Richard Morris and Peter Cudhea of Oracle will discuss ZFS Async Replication Enhancements, exploring design decisions around enhancing the ZFS send and ZFS receive commands to transfer already compressed data more efficiently and to recover from failures without re-sending data that has already been received.

J.R. Tipton, Development Lead, Microsoft, will discuss ReFS v2: Cloning, Projecting, and Moving Data File Systems, presenting new abstractions that open up greater control for applications and virtualization, covering block projection and cloning as well as in-line data tiering.

Poornima Gurusiddaiah and Soumya Koduri of Red Hat will present Achieving Coherent and Aggressive Client Caching in Gluster, a Distributed System, discussing how to implement file system notifications and leases in a distributed system and how these can be leveraged to implement a client side coherent and aggressive caching.

Sriram Rao, Partner Scientist Manager, Microsoft, will present Petabyte-scale Distributed File Systems in Open Source Land: KFS Evolution, providing an overview of OSS systems (such as HDFS and KFS) in this space, and describing how these systems have evolved to take advantage of increasing network bandwidth in data center settings to improve application performance as well as storage efficiency.

Richard Levy, CEO and President, Peer Fusion, will discuss a High Resiliency Parallel NAS Cluster, including resiliency design considerations for large clusters, the efficient use of multicast for scalability, why large clusters must administer themselves, fault injection when failures are the nominal conditions, and the next step of 64K peers.

Join your peers as well – register now at www.storagedeveloper.org. And stay tuned for tomorrow’s blog on Cloud topics at SDC!

New ESF Webcast: Benefits of RDMA in Accelerating Ethernet Storage Connectivity

David Fair

We’re kicking off our 2015 ESF Webcasts on March 4th with what we believe is an intriguing topic – how RDMA technologies can accelerate Ethernet Storage. Remote Direct Memory Access (RDMA) has existed for many years as an interconnect technology, providing low latency and high bandwidth in computing clusters. More recently, RDMA has gained traction as a method for accelerating storage connectivity and interconnectivity on Ethernet. In this Webcast, experts from Emulex, Intel and Microsoft will discuss:

  • Storage protocols that take advantage of RDMA
  • Overview of iSER for block storage
  • Deep dive of SMB Direct for file storage.
  • Benefits of available RDMA technologies to accelerate your Ethernet storage connectivity, both iWARP and RoCE

Register now. This live Webcast will provide attendees with a vendor-neutral look at RDMA technologies and should prove to be an interactive and informative event. I hope you’ll join us!

Cloud File Services: SMB/CIFS and NFS…in the Cloud – Q&A

John Reed

Cloud File Services: SMB/CIFS and NFS…in the Cloud – Q&A

At our recent live ESF Webcast, “Cloud File Services: SMB/CIFS and NFS…in the Cloud” we talked about evaporating your existing file server into the cloud. Over 300 people have viewed the Webcast. If you missed it, it’s now available on-demand. It was an interactive session with a lot of great questions from attendees. We did not have time to address them all – so here is a complete Q&A from the Webcast. If you think of additional questions, please feel free to comment on this blog.

Q. Can your Storage OS take advantage of born-in-the-cloud File Storage like Zadara Storage at AWS and Azure?

A. The concept presented is generic in nature.  Whichever storage OS the customer chooses to use in the cloud will have its own requirements on the underlying storage beneath it.  Most Storage OS’s used for Cloud File Services will likely use block or object backends rather than a file backend.

Q. Regarding Cloud File Services for “Client file services,” since the traditional file services require the client and server to be in a connected mode, and in the same network. And, they are tied to identities available in the network. How can the SMB/NFS protocols be used to serve data from the cloud to the clients that could be coming from different networks (4G/Corporate)? Isn’t REST the appropriate interface for that model?

A. The answer depends on the use case.  There are numerous examples of SMB over the WAN, for example, so it’s not far fetched to imagine someone using Cloud File Services as an alternative to a “Sync & Share” solution for client file services.  REST (or similar) may be appropriate for some, while file-based protocols will work better for others.  Cloud File Services provides the capability to extend into this environment where it couldn’t before.

Q. Is Manila like VMware VSAN or VASA?

A. Please take a look at the Manila project on OpenStack’s website https://wiki.openstack.org/wiki/Manila

Q. How do you take care of data security while moving data from on-premises to cloud (Storage OS)?

A. The answer depends on the Storage OS you are using for your Cloud File Services platform.  If your Storage OS supports encryption, for example, in its storage-to-storage in-flight data transport, then data security in-flight would be taken care of.  There are many facets to security that need to be thought through, including security at rest, some of which may depend on the environment (private/on-premises, service provider, hyperscalar) the Storage OS is sitting in.

Q. How do you get the data out of the cloud?  I think that’s been a traditional concern with cloud storage.

A. That’s the beauty of Cloud File Services!  With data movement and migration provided at the storage-level by the same Storage OS across all locations, you can simply move the data between on-premises and off-premises and expect similar behavior on both ends.  If you choose to put data into a native environment specific to a hyperscalar or service provider, you run the risk of lock-in.

Q. 1. How does one address issue of “chatty” applications over the cloud?  2. File services have “poor” performance for small files. How does one address that issue? Block & Objects do address that issue 3. Why not expose SMB, NFS, Object Interface on the Compute note?

A. 1. We should take this opportunity to make the applications less chatty! :)  One possible solution here is to operate the application and Storage OS in the same environment, in much the same way you would have on-premises.  If you choose a hyperscalar or service provider, for chatty use cases, it may be best to keep the application and storage pieces “closer” together.

2. Newer file protocols are getting much better at this.  SMB 3.02 for instance, was optimized for 8K transactions.  With a modern Storage OS, you will be able to take advantage of new developments.

3. That is precisely the idea: the Storage OS operating in the “compute nodes,” serving out their interfaces, while taking advantage of different backend offerings for cost and scalability.

Q. Most storage arrays NetApp, EMC etc., can provide 5 9s of resilience, Cloud VMs typically offer 3 9′s.  How do you get to 5 9′s with CFS?

A. Cloud File Services (CFS) as a platform can span across all of your environments, and as such, the availability guarantees will depend upon each environment in which CFS is operating.

Q. Why are we “adding” another layer? Why can we just use powerful “NAS” devices that can have different media like NVMe, Flash SSD or HDDs?

A. Traditional applications may not want to change, but this architecture should suit those well.  It’s worth examining that “cloud-ready” model.  Is the goal to be “cloud-ready,” or is the goal to support the scaling, failover, and on-demand-ness that the cloud has the ability to provide?  Shared nothing is a popular way of accomplishing some of this, but it may not be the only way.

The existing interfaces provided by hyperscalars do provide abstraction, but if you are building an application, you run a strong risk of lock-in on any particular abstraction.  What is your exit strategy then?  How do you move your data (and applications) out?

By leveraging a common Storage OS across your entire infrastructure (on-premises, service providers, and hyperscalars), you have a very simple exit strategy, and your exit and mobility strategy become very similar, if not the same, with the ability to scale or move across any environment you choose.

Q. How do you virtualize storage OS? What happens to native storage OS hardware/storage?

A. A Storage OS can be virtualized similar to a PC or traditional server OS.  Some pieces may have to be switched or removed, but it is still an operating system.

Q. Why is your Storage displayed as part of your Compute layer?

A. In the hyperscalar model, the Storage OS is sitting in the compute layer because it is, in effect, running as a virtual machine the same as any other.  It can then take advantage of different tiers of storage offered to it.

Q. My concern is that it would be slower as a VM than a storage controller.  There’s really no guarantee of storage performance in the cloud in fact most hyperscalers won’t give me a good SLA without boatloads of money.  How might you respond to this?

A. Of course with on-premises infrastructure, a company or service provider will have more of a guarantee in the sense that they control the hardware behind it.  However, as we’ve seen, SLA’s continue to improve over time, and costs continue to come down for the Public Cloud.

Q. Does FreeNAS qualify as a Storage OS?

A. I recommend checking with their team.

Q. Isn’t this similar to Hybrid cloud?

A. Cloud File Services (CFS) is one way of looking at Hybrid Cloud.  Savvy readers and listeners will pick up that having the same Storage OS everywhere doesn’t necessarily limit you to only File Services. iSCSI or RESTful interfaces could work exactly the same.

Q. What do you mean by Storage OS? Can you give some examples?

A. As I work for NetApp, one example is Data ONTAP.  EMC has several as well, such as one for the VNX platform.  Most major storage vendors will have their own OS.

Q. I think one of the key questions is the data access latency over WAN, how I can move my data to the cloud, how I can move back when needed – for example, when the service is terminated?

A. Latency is a common concern, and connectivity is always important.  Moving your data into and out of the cloud is the beauty of the Cloud File Services platform, as I mentioned in other answers.  If one of your environments goes down (for example, your on-premises datacenter) then you would feasibly be able to shift your workloads over to one of your other environments, similar to a DR situation.  That is one example of where storage replication and application awareness across sites is important.

Q. Running applications like Oracle, Exchange through SMB/NFS (NAS), don’t you think it will be slow compared to FC (block storage)?

A. Oracle has had great success running over NFS, and it is extremely popular.  While Exchange doesn’t currently support running directly over SMB at this time, it’s not ludicrous to think that it may happen at some point in the future, in the same way that SQL has.

Q. What about REST and S3 API or are they just for object storage?  What about CINDER?

A. The focus of this presentation was only File Services, but as I mentioned in another answer, if your Storage OS supports these services (like REST or S3), it’s feasible to imagine that you could span them in the same way that we discussed CFS.

Q. Why SAN based application moving to NAS?

A. This was discussed in one of the early slides in the presentation (slide 10, I believe).  Data mobility and granular management were discussed, as it’s easier to move, delete, and otherwise manage files than LUNs, an admin can operate at a more granular level, and it’s easier to operate and maintain.  No HBA’s, etc.  File protocols are generally considered “easier” to use.

 

 

New Webcast: Cloud File Services: SMB/CIFS and NFS…in the Cloud

David Fair

Imagine evaporating your existing file server into the cloud with the same experience and level of control that you currently have on-premises. On October 1st, ESF will host a live Webcast that introduces the concept of Cloud File Services and discusses the pros and cons you need to consider.

There are numerous companies and startups offering “sync & share” solutions across multiple devices and locations, but for the enterprise, caveats are everywhere. Register now for this Webcast to learn:

  • Key drivers for file storage
  • Split administration with sync & share solutions and on-premises file services
  • Applications over File Services on-premises (SMB 3, NFS 4.1)
  • Moving to the cloud: your storage OS in a hyperscalar or service provider
  • Accommodating existing File Services workloads with Cloud File Services
  • Accommodating cloud-hosted applications over Cloud File Services

This Webcast will be a vendor-neutral and informative discussion on this hot topic. And since it’s live, we encourage your to bring your questions for our experts. I hope you’ll register today and we’ll look forward to having you attend on October 1st.   

 

Upcoming Plugfests at SDC

Jason Blosil

This year’s SNIA Storage Developer Conference (SDC) will take place in Santa Clara, CA Sept. 15-18.  In addition to an exciting agenda with great speakers, there is an opportunity for vendors to participate in SNIA Plugfests. Two Plugfests that I think are worth noting are: SMB2/SMB3 and iSCSI.

These Plugfests enable a vendor to bring their implementations of SMB2/SMB3 and/or iSCSI to test, identify, and fix bugs in a collaborative setting with the goal of providing a forum in which companies can develop interoperable products. SNIA provides and supports networks and infrastructure for the Plugfest, creating a collaborative framework for testing. Plugfest participants work together to define the testing process, assuring that objectives are accomplished.

Still Time to Register

Great news! There is still time to register. Setup for the Plugfest begins on September 13, 2014 and testing begins on the September 14th.

Register here for the SMB2/SMB3 Plugfest

Register here for the iSCSI Plugfest

What to Expect at a Plugfest

Learn more about what takes place at the Plugfests by watching the video interview of Jeremy Allison, Co-Creator of Samba, as he candidly talks about what to expect at an SDC Plugfest.

Learn more about the Plugfest registration process. If you have additional questions, please contact Arnold Jones (arnold@snia.org).

 

SMB 3.0 – Your Questions Asked and Answered

AlexMcDonald

Last week we had a large and highly-engaged audience at our live Webcast: “SMB 3.0 – New Opportunities for Windows Environments.” We ran out of time answering all the questions during our event so, as promised, here is a recap of all the questions and answers to attendees’ questions. The Webcast is now available on demand at http://snia.org/forums/esf/knowledge/webcasts. You can also download a copy of the presentation slides there.

Q. Have you tested SMB Direct over 40Gb Ethernet or using RDMA?

A. SMB Direct has been demonstrated using 40Gb Ethernet using TCP or RDMA and Infiniband using RDMA.

Q. 100 iops, really?

A. If you look at the bottom right of slide 27 (Performance Test Results) you will see that the vertical axis is IOPs/sec (Normalized). This is a common method for comparing alternative storage access methods on the same storage server. I think we could have done a better job in making this clear by labeling the vertical axis as “IOPs (Normalized).”

Q. How does SMB 3.0 weigh against NFS-4.1 (with pNFS)?

A. That’s a deep question that probably deserves a webcast of its own. SMB 3 doesn’t have anything like pNFS. However many Windows workloads don’t need the sophisticated distributed namespace that pNFS provides. If they do, the namespace is stitched together on the client using mounts and DFS-N.

Q. In the iSCSI ODX case, how does server1 (source) know about the filesystem structure being stored on the LUN (server2) i.e. how does it know how to send the writes over to the LUN?

A. The SMB server (source) does not care about the filesystem structure on the LUN (destination). The token mechanism only loosely couples the two systems. They must agree that the client has permission to do the copy and then they perform the actual copy of a set of blocks. Metadata for the client’s file system representing the copied file on the LUN is part of the client workflow. Client drag/drops file from share to mounted LUN. Client subsystem determines that ODX is available. Client modifies file system metadata on the LUN as part of the copy operation including block maps. ODX is invoked and the servers are just moving blocks.

Q. Can ODX copies be within the same share or only between?

A. There is no restriction to ODX in this respect. The resource and destination of the copy can be on same shares, different shares, or even completely different protocols as illustrated in the presentation.

Q. Does SMB 3 provide API for integration with storage vendor snapshot other MS VSS?

A. Each storage vendor has to support Microsoft Remote VSS protocol, which is part of SMB 3.0 protocol specification. In Windows 2012 or Windows 8 the VSS APIs were extended to support UNC share path.

Q. How does SMB 3 compare to iSCSI rather than FC?

A. Please examine slide 27, which compares SMB 3, FC and iSCSI on the same storage server configuration.

Q. I have a question between SMB and CIFS. I know both are the protocols used for sharing. But why is CIFS adopted by most of the storage vendors? We are using CIFS shares on our NetApps, and I have seen that most of the other storage vendors are also using CIFS on their NAS devices.

A. There has been confusion between the terms “SMB” and “CIFS” ever since CIFS was introduced in the 90s. Fundamentally, the protocol that manages the data transfer between and client and server is SMB. Always has been. IMO CIFS was a marketing term created in response to Sun’s WebNFS. CIFS became popularized with most SMB server vendors calling their product a CIFS server. Usage is slowly changing but if you have a CIFS server it talks SMB.

Q. What is required on the client? Is this a driver with multi-path capability? Is this at the file system level in the client? What is needed in transport layer for the failover?

A. No special software or driver is required on the client side as long as it is running Windows 8 and later operating environment.

Q. Are all these new features cross-platform or is it something only supported by Windows?

A. SMB 3 implementations by different storage vendors will have some set of these features.

Q. Are virtual servers (cloud based) vs. non-virtual transition speeds greatly different?

A. The speed of a transition, i.e. failover is dependent on two steps. The first is the time needed to detect the failure and the second is the time needed to recover from that failure. While both a virtual and a physical server support transition the speed can significantly vary due to different network configurations. See more with next question.

Q. Is there latency as it fails over?

A. Traditionally SMB timeouts were associated with lower level, i.e. TCP timeouts. Client behavior has varied over the years but a rule-of-thumb was detection of a failure in 45 sec. This error would be passed up the stack to the user/application. With SMB 3 there is a new protocol called SMB Witness. A scale-out SMB server will include nodes providing SMB shares as well those providing Witness service. A client connects to SMB and Witness. If the node hosting the SMB share fails, the Witness node will notify the client indicating the new location for the SMB share. This can significantly reduce the time needed for detection. The scale-out SMB server can implement a proprietary mechanism to quickly detect node failure and trigger a Witness notification.

Q. Sync or Async?

A. Whether state movement between server nodes is sync or async depends on vendor implementation. Typically all updated state needs to be committed to stable storage before returning completion to the client.

Q. How fast is this transition with passing state id’s between hosts?

A. The time taken for the transition includes the time needed to detect the failure of Client A and the time needed to re-establish things using Client B. The time taken for both is highly dependent on the nature of the clustered app as well as the supported use case.

Q. We already have FC (using VMware), why drop down to SMB?

A. If you are using VMware with FC, then moving to SMB is not an option. VMware supports the use of NFS for hypervisor storage but not SMB.

Q. What are the top applications on SMB 3.0?

A. Hyper-V, MS-SQL, IIS

Q. How prevalent is true “multiprotocol sharing” taking place with common datasets being simultaneously accessed via SMB and NFS clients?

A. True “multiprotocol sharing” i.e. simultaneous access of a file by NFS & SMB clients is extremely rare. The NFS and SMB locking models don’t lend themselves to that. Sharing of a multiprotocol directory is an important use case. Users may want access to a common area from Linux, OS X and Windows. But this is sequential access by one OS/protocol at a time not all at once.

Q. Do we know growth % split between NFS and SMB?

A. There is no explicit industry tracker for the protocol split and probably not that much point in collecting them either, as the protocols aren’t really in competition. There is affinity among applications, OSes and protocols – MS products tend to SMB (Hyper-V, SQL Server,…), and non-Microsoft to NFS (VMware, Oracle, …). Cloud products at the point of consumption are normally HTTP RESTless protocols.