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Architecting Virtual SAP HANA Using VMware Virtual Volumes And Hitachi Storage

VMWorld Recap: SAP HANA and VMware Virtual Volumes

This is a follow up to my earlier VMWorld blog; “Virtualizing SAP HANA Databases Greater Than-1TB On vSphere-5-5”, where I discussed SAP Multi-Temperature Data Management strategies and techniques which can significantly reduce the size and cost associated with SAP HANA’s in-memory footprint. This blog will focus on Software-Defined Storage and the need for VMware Virtual volumes when deploying Mission Critical Applications/Databases like SAP HANA as discussed in my VMWorld session.

Multi-Temperature Data Management Is By Definition Software-Defined Storage

SAP and VMware customers who plan on leveraging multi-temperature strategies, where data is classified by frequency of access as either hot, warm or cold depending on data usage is the essence of Software-Defined Storage. This can also be equated to EMC’s Information Lifecycle Management which examines the value of data to the business over time. To bring the concept of the Software-Defined Data Center and more precisely Software-Defined Storage to reality, see Table 1. This table depicts the various storage options for SAP HANA so customers can create an architecture that aligns with the business and its applications demands.

Table 1: Multi-Temperature Storage Options with SAP HANA


Planning Your Journey To Software-Defined Storage

As we get into the various storage options for SAP HANA, VMware has made it very easy to create and deploy software defined storage in the form of Virtual Volumes. However I want to stress the actual definitions of how the storage should be abstracted is a collaborative task, at a minimum you must involve the storage team, VI-Admins, application owners, and dba’s in order to create an optimized virtual architecture; this should not be a siloed task.

In my previous post I discussed the storage requirements for SAP HANA In-Memory, Dynamic Tiering, Near-Line Storage, and the Archiving Components; one last option I did not cover in Table 1 is Data Aging which is specific to SAP Business Suite. Under normal operations SAP HANA does not preload data into memory, data is loaded upon first access, so the first time you access data its always off disk.

With Data Aging you can essentially mark data so its never loaded into memory and will always reside on disk. This is not available on all modules for Business Suite, so please check with SAP for availability and roadmap with respect to Data Aging.

Essentially this is another SAP HANA feature which enables customers to reduce and manage their memory footprint more efficiently and effectively. The use of Data Aging can change the design requirements of your Software-Defined Storage, if Data Aging becomes more prevalent in your SAP Landscape, VMware Virtual Volumes can be used to address the changing storage requirements of the application by seamlessly migrating data between different classes of software-defined storage or VMDKs.

VMware Virtual Volumes Transform Storage By Aligning With SAP HANA’s Requirements

Now lets get into Virtual Volumes and the problems they solve, with Virtual Volumes the fundamental model is centered around provisioning storage based on the application needs rather than the underlying infrastructure. When deploying SAP HANA using the Tailored Data Center Integration model, the storage KPIs can be quite complex, so how do customers translate latency, throughput for reads – writes – and updates, at various block sizes to the storage layer?

Plus how does a customer address the storage requirements for SAP HANA’s entire data life cycle, whether you are planning on using Dynamic Tiering, with or without Near-Line-Storage and what is the archiving strategy storage requirements as well. Also some of the storage requirements do tie back to the compute layer, as an example with Dynamic Tiering if you plan on using Row Level Versioning there is a compute to memory relationship for storage that comes into play when sizing

Addressing and achieving these design goals using an infrastructure centric model can be quite difficult because you are tied to physical LUNs and trust me, with mission critical databases, you will always have database administrators fighting over LUNs with the lowest numbers because of the concerns around radial density. This leads to tremendous waste when provisioning storage using an infrastructure centric model.

VMware Virtual Volumes significantly reduces the storage design complexity by using an Application Centric model because you are not dealing with storage at the LUN level, instead vSphere admins use policies to express the application requirements to the storage array, then the storage array maps storage containers to the application requirements.

What are VMware Virtual Volumes?

At a high level I’ll go over the architecture and components of Virtual Volumes, this blog is not intended to be a deep dive into Virtual Volumes, instead my goal is to convey that mission critical uses cases for VVOLS and software-defined storage are real. For an excellent white paper on Virtual Volumes see; “VMware vSphere Virtual Volumes Getting Started Guide”.

As shown in Figure 1., Virtual Volumes are a new type of virtual machine object which are created and stored natively on the storage array. The Vendor Provider also known as the VASA Provider, which are the vSphere Storage APIs for Storage Awareness (VASA) that provide the storage awareness services and mediates out of the box communications between vCenterServer and EXi Hosts on one side and the storage system on the other side.

The storage containers are pools of raw storage that a storage system can provide to virtual volumes and unlike LUNS and NFS, they do not require pre-configured volumes on the storage side. Also with virtual volumes you still have the functionality you would expect when using native VMDKs

Virtual Datastores represents a storage container in a vCenter Server instance, so it’s a 1:1 mapping to the storage systems storage container. The ESXi Hosts have no direct access to the virtual volumes on the storage side, so they use a logical I/O proxy called a protocol endpoint and as you would expect VVOLs are compatible with industry standard protocols, iSCSI, NFS, FC, and FCoE

The Published Storage Capabilities will vary by storage vendor depending on which capabilities have been exposed and implemented. In this blog we will be looking at the exposed capabilities of Hitachi Data Systems like latency, throughput, Raid Level, Drive Type/Speed, IOPS, and Snapshot frequency to mention a few.

Figure 1: vSphere Virtual Volumes Architecture and Components


VMware HDS: Creating Storage Containers, Virtual Volumes, and Profiles for Virtual SAP HANA

Now Virtual Volumes are an Industry-wide Initiative, essentially a who’s who of the storage industry are participating in this initiative, however this next section will be representative of the work done with Hitachi Data Systems

And again the guidance here is collaboration when architecting software-defined storage for SAP HANA landscapes and for that matter any mission critical application or database. Because the beauty of software defined storage is once created and architecture correctly you can then provision your virtual machines in an automated and consistent manner.

So in the spirit of collaboration, I got together with Hitachi’s SAP alliance team, their storage team, and database architects and we came up with these profiles, policies, and containers to use when deploying SAP HANA landscapes.

We had several goals when designing this architecture; one was to use virtual volumes to address the entire data life cycle of SAP HANA, the in-memory component, Dynamic Tiering, Near-Line storage, and archiving or any supported combination of the above when creating a SAP HANA landscape. And secondly we wanted to enable rapidly provisioning of SAP HANA landscapes, so we created profiles, policies, and containers which could be used to deploy SAP HANA databases whose in-memory component could range from 512GB to 1TB in size.

I’ll review some of the capabilities HDS exposed which were used for this architecture:

  • Interestingly enough we were able to meet the SAP HANA in-memory KPIs using Hitachi Tier 2 storage which consisted of 10K SAS drives for both log and data files, as well as for the Operating System and the SAP HANA shared file system. This also simplified the design. We then used high density SAS drives for the backup areas
  • We enabled automatic storage managed snapshots for HANA data, log and the OS; and set the Snapshot frequency based on the classifications of Critical, Important, or Best Effort.
  • So snapshots for the data and log were classified as Critical while the OS was classified as Important and the backup area we didn’t snapshot at all
  • We also tagged this storage as certified, capturing the model and serial number, since the SAP HANA in-memory component requires certified storage. We wanted to make sure that when creating HANA VM’s you’re always pulling from certified storage containers.
  • The Dynamic Tiering and NLS storage had similar requirements so could be provisioned from the same containers and since these are disk based columnar databases we selected Tier 1 storage SSDs for the data files based on the random read/write patterns
  • And stuck with SAS drives for the log files since sequential workload don’t benefit much from SSDs. Again because of the disk based access we selected Tier 2 to satisfy the IOPS and Latency requirements.
  • Then finally for the archiving containers we used the lowest cost & highest density storage, pretty much just a file system.

Now there’s just too much information to cover in this effort with HDS but for those of you interested, VMware and Hitachi we will be publishing a Co-Logo White Paper which will be a much deeper dive into how we architected these landscapes so customers can do this almost out of the box.

Deploying VMware Software-Defined Storage With vSphere and Hitachi Command Suite

Example: SAP HANA Dynamic Tiering and Near-Line Storage Tiers. These next couple of screen captures will show how simple virtual volumes are to deploy once architected correctly

Figure 2: Storage Container Creation: SAP HANA DT and NLS Tier


Figure 3: Create Virtual Machine Storage Policies SAP HANA DT/NLS Data/Log File


Figure 4: Create New SAP HANA DT VM Using VVOLS Policies With Hitachi Storage


Addressing Mission Critical Use Cases with VMware Software-Defined Storage

SAP HANA and Multi-Temperature Data Management is the poster child for mission critical software-defined storage use cases. VMware Virtual Volumes solves the complexities and simplifies storage provisioning by using an application centric model rather than an infrastructure centric model.

The SAP HANA in-memory component is not yet certified for production use on vSphere 6.0, however Virtual Volumes can be used for SAP HANA Dynamic Teiring, Near-Line Storage, and Archiving. So my advice to our customers is to start architecting now, get together with your storage admins, VI Admins, application owners, and database administrators to create containers, policies, and profiles correctly so when vSphere 6.0 is certified you are ready to “Run SAP HANA Simple”.



VMWorld Topic: Virtual Volumes (VVOLS) a game changer for running Tier 1 Business Critical Databases

One of the major components released with vSphere 6 this year was the support for Virtual Volumes (VVOLS). VVOLS has been gaining momentum with storage vendors, who are enabling its capabilities in their arrays.

When virtualizing business databases there are many critical concerns that need to be addressed that include:

  1. Database Performance to meet strict SLAs
  2. Daily Operations e.g. Backup & Recovery to complete in set window
  3. Cut down time to Clone / Refresh of Databases from Production
  4. Meet different IO characteristics and capabilities based on criticality
  5. Never ending debate with DBAs
  6. File Systems v/s Raw Devices (VMFS v/s RDM)

VVOLS can offer solutions to mitigate these concerns that impact the decision to virtualize business critical databases. VVOLS can help with the following:

1. Reduce backup windows for databases
2. Provide ability to have Database consistent backups
3. Reduced cloning times for multi-terabyte databases
4. Provide capabilities for Storage Policy based management

Details on the solutions available with VVOLS and its impact on “Virtualized Tier1 Business Critical Databases” will be discussed in detail at vmworld 2015 in session STO4452:

STO4452 –  STO4452 – Virtual Volumes (VVOLS) a game changer for running Tier 1 Business Critical Databases
Session Date/Time: 08/31/2015 03:30 PM – 04:30 PM

Use VSAN Assessment to validate Virtual SAN’s benefits for your organization

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vSphere with Operations Management Product Walkthroughs

If you’ve ever tried to watch a product demo video, or tried to use it to show a product to someone else, often times you find yourself trying to pause the video at the exact right moment, and then having scrub backwards or forwards because you missed the timing.  At VMware we’ve created an alternative way ot showing demos, which we call Product Walkthroughs.  These are web-based demos that let you walk through a scenario screen-by-screen, at your own pace.  Each screen has annotations to explain what’s going on and markups that highlight important parts of the screen, both of which can be turned off if you want a clean view.

Although we have created Product Walkthroughs for numerous products and solutions, the ones I want to focus on are for vSphere 6 and vSphere with Operations Management.  Both of these provide a great way to learn about these products and their features at your own pace, as well as to show how something works to your colleagues (or bosses).  The one on vSphere 6 highlights the features in this major new release, with sections on:

and more.

The vSphere with Operations Management product walkthrough provides an in-depth look at all the features of its two major components, vSphere and vRealize Operations, including

So, check them out and let us know what you think!

What’s New with Virtual SAN 6.0?

Software-Defined Storage is making waves in the storage and virtual infrastructure fields. Data and infrastructure are intertwined, and when they’re both brought together, companies can cut down on expenses and increase productivity.

Rawlinson Rivera, Principal Architect, Storage and Availability, recently hosted a webinar, discussing how VMware is approaching Software-Defined Storage (SDS) and virtualization in recently announced VMware updates, including updates to VMware Virtual SAN 6.0.

Software-defined storage offers organizations the ability automate, distribute and control storage better than ever before. SDS can provision storage for applications on demand and without complex processes. It also allows for standardized hardware, reducing costs for businesses everywhere.

To bring the customers the best software-defined storage experience to realization, we had to update VMware® Virtual SAN™. And we did just that. With VMware Virtual SAN 6.0, we introduced several new features with SDS in mind:

  • Software-defined storage optimized for VMs
  • All Flash architecture
  • Broad hardware support
  • The ability to run on any standard x86 server
  • Enterprise-level scalability and performance
  • Per-VM storage policy management
  • And a deep integration with the VMware stack

There’s a lot more to unpack from the latest updates to our VMware solutions. For a more in-depth guide to what’s new and how it affects you, watch the webcast here!

Be sure to subscribe to the Virtual SAN blog or follow our social channels at @vmwarevsan and Facebook.com/vmwarevsan for the latest updates.

For more information about VMware Virtual SAN, visit http://www.vmware.com/products/virtual-san.

Virtual SAN Certification & VCG Update

The Virtual SAN product team is pleased to announce that last week we released new certified components (I/O controllers, SSDs and HDDs), new Ready Nodes and a new Hardware Quick Reference Guide for Virtual SAN 6.0 along with a new and improved VCG page.  Please see updated links below:

Updated Virtual SAN VCG

Updated Virtual SAN Hardware Quick Reference Guide

Updated Virtual SAN Ready Nodes


How many new components and Ready Nodes do we have listed for Virtual SAN 6.0?

We now have 26 I/O controllers, 170 SSDs and 125 HDDs (and counting) supported on Virtual SAN 6.0.   In addition to the Virtual SAN 5.5 Ready Nodes, we have 8 new Ready Nodes for Virtual SAN 6.0  (Cisco – 4 Hybrid, Dell – 1 Hybrid, Hitachi – 1 Hybrid, Super Micro – 1 All Flash & 1 Hybrid).

We expect this list to grow very quickly.  We have a number of components that are currently getting certified and we plan to add new certified devices and Ready Nodes to the VCG on a weekly basis.


How does the Virtual SAN Certification process work?

The VMware Virtual SAN team treats hardware certification very seriously.  I/O controllers play a very important part in determining the stability and performance of a Virtual SAN cluster and need to be able to withstand high I/O under stress conditions.

The I/O controllers are put through a rigorous I/O certification process while the HDD, SSD and Ready Nodes  are put through stringent paper qualifications.

We run a I/O controller card through a 3-week-long certification test plan (the certification is done by VMware or by the partner) that stress tests the card across many dimensions, particularly in high load and failure scenarios to ensure the card can withstand the level of I/O pushed down by Virtual SAN even in the most adverse situations (example: rebuilds and resyncs triggered due to host failures).

If there are issues identified, we work closely with our controller vendor/OEM partner to resolve them and re-run the entire test suite after resolution.  Sometimes an updated firmware or driver version addressing the issue is required from the vendors before we can proceed with more testing.

Only controllers that fully pass the test criteria laid out in the above process are listed on the Virtual SAN VCG.


Are separate I/O controller certifications required for different releases?

Yes, we require controllers to be recertified whenever any of the following change:

  • Virtual SAN Release version (eg: 5.5 to 6.0)
  • The controller driver version
  • The controller firmware version

We also certify the same controller separately for Virtual SAN All Flash vs Hybrid since the caching and I/O mechanism are different for these two configurations and we expect controllers to behave differently with varying levels of I/O.


What about certification of PCIe-SSD devices?

PCIe-SSDs are nothing but SSDs with an on-board I/O controller in a PCIe form factor.  Therefore, these require the same level of due diligence as required by standard I/O controllers.  As a result, we are putting these devices through the same level of rigorous certification as we do for I/O controllers.

VMware is working very closely with partners to certify the first set of PCIe-SSDs for Virtual SAN 6.0 over the coming weeks.


What are the new updates to the VCG page?

The Virtual SAN VCG page has been enhanced to allow users to easily build or choose their All Flash configurations in addition to Hybrid configurations.  Since All Flash Virtual SAN requires SSDs of different endurance and performance spec for caching and performance tiers (See Updated Virtual SAN Hardware Quick Reference Guide for details on specs), we have enhanced the VCG to help users easily pick SSDs for the tier they are interested in.

We have also introduced a new SSD filter called “Virtual SAN type” to help easily filter our All Flash vs Hybrid configurations.  Furthermore, we have added a filter called “Tier” to help you filter our Virtual SAN hybrid caching, Virtual SAN All Flash caching and Virtual SAN capacity caching tiers.

The endurance rating for SSDs are now displayed on the VCG in TBW (Terabytes written over 5 years) as opposed to DWPD (Drive Writes Per Day) which was used previously.


What are the controllers that are currently in the certification queue and when do we expect them to get certified?

Please see the attached list of controllers that are currently undergoing Virtual SAN certification

Note:  In many cases, we rely on our partners to provide driver/firmware fixes for controller issues so if there are delays in receiving these updates from partners, the certification timelines may get pushed out.

Having said that, we are making good progress on most of the controllers listed in the attached document and expect them to follow our standard certification process.

On a similar note, Ready Nodes  are primarily dependent on the controllers getting certified, so as you see new controllers on the VCG for 6.0 certified, Ready Nodes  including those controllers will follow.

Video: Virtual SAN From An Architect’s Perspective

Video: Virtual SAN From An Architect’s Perspective

Have you ever wanted a direct discussion with the people responsible for designing a product?

Recently, Stephen Foskett brought a cadre of technical bloggers to VMware as part of Storage Field Day 7 to discuss Virtual SAN in depth.  Christos Karamanolis (@XtosK), Principle Engineer and Chief Architect for our storage group went deep on VSAN: why it was created, its architectural principles, and why the design decisions were important to customers.

The result is two hours of lively technical discussion — the next best thing to being there.  What works about this session is that the attendees are not shy — they keep peppering Christos with probing questions, which he handles admirably.

The first video segment is from Alberto Farronato, explaining the broader VMware storage strategy.

The second video segment features Christos going long and deep on the thinking behind VSAN.

The third video segment is a run-over of the second.  Christos presents the filesystem implementations, and the implications for snaps and general performance.

Our big thanks to Stephen Foskett for making this event possible, and EMC for sponsoring our session.


VMware Virtual SAN 6.0 Now Generally Available

Virtual SAN 6 – you heard about it in February… thousands of you read about it in Rawlinson’s blog post… and today you can get your hands on it. Virtual SAN 6 is now generally available (GA) – download your evaluation version today! For those of you who missed Rawlinson’s blog post describing the details around what’s new with Virtual SAN 6 – you can read it here (below). But there’s a better way to get the information – register and attend this week’s webinar on “What’s New with Virtual SAN 6” hosted by Rawlinson Rivera – we’ll see you there!


It is with great pleasure and joy that I like to announce the official launch of VMware Virtual SAN 6.0, one of VMware’s most innovative software-defined storage products and the best hypervisor-converged storage platform for virtual machines. Virtual SAN 6.0 delivers a vast variety of enhancements, new features to the as well as performance and scalability improvements.

Virtual SAN 6.0 introduces support for an all-flash architecture specially designed to provide virtualized applications high performance with predictably low latencies. Now with support for both hybrid and all-flash architectures Virtual SAN 6.0 is ready to meet the performance demands of just about any virtualized application by delivering consistent performance with sub-millisecond latencies.

Hybrid Architecture

  • In the hybrid architecture, server-attached magnetic disks are pooled to create a distributed shared datastore that persists the data. In this type of architecture, you can get up to 40K IOPS per server host.

All-Flash Architecture

In All-Flash architecture, the flash-based caching tier is intelligently used as a write-buffer only while another set of flash devices forms the persistence tier to store data. Since this architecture utilizes only flash devices, it delivers extremely high IOPs of up to 90K per host, with predictable low latencies.


Virtual SAN 6.0 delivers true enterprise-level scale and performance by doubling the scalability of Virtual SAN 5.5 by scaling up to 64 nodes per cluster for both hybrid and all-flash configurations. In addition, Virtual SAN 6.0 improves the number of virtual machines per host up to 200 for both supported architectures.


The performance enhancements delivered in Virtual SAN 6.0 are partially due to the new Virtual SAN on-disk Filesystem (VSAN FS). The new version delivers a new VMDK delta file (vsanSparse) takes advantage of the new on-disk format writing and extended caching capabilities to deliver efficient performance. This results in the delivery of performance-based snapshots, and clone that are comparable to SAN snapshots.

Virtual SAN 6.0 now enables intelligent placement of virtual machine objects across server racks for enhanced application availability even in case of complete rack failures. Virtual SAN Fault Domains provide the ability to group multiple hosts within a cluster to define failure domains to ensure replicas of virtual machines data is spread across the defined failure domains (racks).


Along with all the new added features a significant amount of improvements have been added to enhance the management user experience:

  • Disk/Disk Group Evacuation – Introduce ability to evacuate data from individual disk/disk groups before removing a disk/disk group from the Virtual SAN.
  • Disk Serviceability features – easily map the location of magnetic disks and flash devices. Ability light disk LED on failures, Turn disk LED on/off from the vSphere Web Client.
  • Storage Consumption Models – adds functionality to visualize Virtual SAN 6.0 datastore resource utilization when a VM Storage Policy is created or edited.
  • UI Resynchronization Dashboard – the vSphere Web Client UI displays virtual machine objects resynchronization status and remaining bytes to sync.
  • Proactive Rebalance – provides the ability to manually trigger a rebalance operation in order to utilize newly added cluster storage capacity.
  • Health Services – deliver troubleshooting and health reports to vSphere Administrators about Virtual SAN 6.0 subsystems and their dependencies such as cluster, network, data, limits, physical disk.


With all the major enhancements and features of this release, Virtual SAN is now enterprise-ready, and customers can use it for a broad range of use cases, including business-critical and tier-1 production applications.  Stay tune, there is a lot more to come from the world’s greatest software-defined storage platform. For more information visit the Virtual SAN product page.

– Enjoy

For future updates on Virtual SAN (VSAN), vSphere Virtual Volumes (VVOLs) and other Software-defined Storage technologies as well as vSphere + OpenStack be sure to follow me on Twitter: @PunchingClouds

Be sure to subscribe to the Virtual SAN blog or follow our social channels at @vmwarevsan and Facebook.com/vmwarevsan for the latest updates.

For more information about VMware Virtual SAN, visit http://www.vmware.com/products/virtual-san.





Storage Blog Recap: Top Blogs from January

The third week of every month, we will be compiling a list of the top vSphere Storage posts from the previous month for you to digest.

Here are the top storage blogs from January:

VMware Virtual SAN: File Services with NexentaConnect

Rawlinson Rivera discusses NexentaConnect for Virtual SAN, a software-defined storage solution designed specifically to deliver file service on top of Virtual SAN.

SAP HANA Dynamic Tiering and the VMware Software Defined Data Center

The latest release of SAP HANA has brought the concepts of multiple-temperature data and lifecycle management to a new level. Bob Goldsand talks more about this, as well as native use cases and dynamic tiering with VMware HA and workload management.

Storage and Availability at Partner Exchange 2015

VMware Partner Exchange just wrapped up in San Francisco, California. In this post, Ken Werneburg talks about some key storage and availability sessions that were offered during the conference.

Discover Software-Defined Storage and VMware Virtual SAN at PEX 2015!

The Virtual SAN team highlights some of the can’t-miss sessions that were available to attendees of VMware Partner Exchange 2015.

Performance Unplugged: Demanding Applications

Mark Achtemichuk introduces a new series called “Performance Unplugged”, which showcases a number of talented performance gurus and also covers commonly asked questions and topics.

Be sure to subscribe to the Virtual SAN blog or follow our social channels at @vmwarevsan and Facebook.com/vmwarevsan for the latest updates.

For more information about VMware Virtual SAN, visit http://www.vmware.com/products/virtual-san.

One Cloud, Any Application – #VMW28days

Screen Shot 2015-02-09 at 4.11.51 PM

VMware Virtual SAN 6.0 – you heard all about it on February 2nd – you read all about it in our blog post on the vSphere Storage Blog.


Still want more?


Visit VMware’s One Cloud, Any Application site every day in February to learn more about our products and solutions including software-defined storage, Virtual SAN 6, and Virtual Volumes (VVOLs). With content for IT decision makers and practitioners alike, this site contains everything from technical documentation to infographics, whitepapers, and analyst insights.


Stop by today!


Also, this Thursday, February 12th, at 11am PST, we would like to invite you to join the software-defined storage CrowdChat! Here, you’ll be able to ask questions directly to VMware storage experts. RSVP today!


For more information about VMware Virtual SAN, follow us on Twitter at @VMwareVSAN and Facebook at facebook.com/vmwarevsan.