We’ve loved Brien Posey’s series on server hardware. Now that it’s wrapped up (all 9 parts!) it’s worth a look at the whole.

In many ways server hardware really isn’t all that different from desktop PC hardware. Both use the same basic components such as memory, CPUs, and power supplies. In spite of these similarities however, server hardware can seem completely foreign to those who have previously only dealt with desktop hardware. The individual components tend to be more advanced than the components that are found in desktop computers. Servers may also make use of redundant and / or how swappable components. Occasionally PCs might have redundant or even hot swappable components, but such features are much more common on servers.

© Stephen Foskett for Gestalt IT, 2012. | Server Hardware Explained
Read more posts categorized as Desktop, Server Virtualization

An interesting thought about converged infrastructure. As Dwayne says:

The issue that I have with converged infrastructure is that it’s solving a problem that these companies helped to create

© Stephen Foskett for Gestalt IT, 2012. | So Your Boss Thinks You’re Stupid – Converged Infrastructure
Read more posts categorized as Server Virtualization, Storage

I’m not sure that everyone would agree that Storage DRS is the most exciting new feature in vSphere 5, but it’s certainly in the top 10. Here’s Duncan Epping’s overview of Storage DRS and datastore clusters. Nice video too!

vSphere 5.0 introduces many great new features, but everyone will probably agree with us that vSphere Storage DRS is most the exciting new feature.

© Stephen Foskett for Gestalt IT, 2012. | An introduction to Storage DRS
Read more posts categorized as Server Virtualization, Storage

Chris Wahl goes deep and geeky into the latest beta of Xangati’s VDI monitoring tool. It’s worth taking a look to see what they’re up to!

The Xangati Dashboard has quickly become my go-to tool for figuring out any issues in the lab, or purposely designing issues to better understand how they impact other systems. As a matter of full disclosure: I was provided a handful of socket licenses under NFR, which basically provide the same features as their trial product, but without an expiration date. Point being – anything you read about in my posts can essentially be explored using their free tool (for a single host) or a trial (for a cluster).

© Stephen Foskett for Gestalt IT, 2012. | Xangati Introduces Performance Profiling for VDI End-Users
Read more posts categorized as Desktop, Server Virtualization

Cisco’s UCS B-Series is an exemplary modern blade system

Blade servers are easily recognized in the data centers, trade shows, and product catalogs of today: They’re the ones that nestle together in an enclosure, sharing some resources rather than standing on their own in a rack or on the floor. But what is the essential element that separates a blade from any other kind of server?

Let’s consider some defining characteristics of the blade server species:

1. Physically, a rack-mounted blade enclosure contains a number of server blades. Each blade is smaller than a 19″ rack, allowing more to be packed into the same space. This contrasts with larger, self-enclosed tower or rack-mount servers.
2. Server blades rely on the blade enclosure for critical supporting functions like power, cooling, and I/O ports, so they cannot stand alone. This further improves density and efficiency. Stand-alone servers, on the other hand, include these functions in their case.
3. Blade systems include some sort of management device that monitors the blades and can control some of their functions. Conventional servers do not always have this kind of consolidated management.
4. The blade chassis includes consolidated and shared I/O channels, ranging from keyboard, video, and mouse (KVM) to networking and storage (usually Ethernet and Fibre Channel). These add flexibility, since external ports can be shared by multiple blades and reconfigured without disruption.
5. Blade systems are optimized for high availability, with hot-swap components everywhere from power to fans to the blades themselves. Since these are shared, it is more efficient to purchase redundant parts for a blade system than for each server individually.

HP’s blade systems (like this loaded c3000) make up half the market today

To me, these five elements are key to a modern blade system. Without them, a blade solution cannot meet the expectations of buyers (or the promises of vendors!) And what are these benefits? I took a look at the marketing materials for the leading companies in the space (HP, Dell, IBM, and Cisco), and this is what they promise:

1. Efficiency – More processing power in a smaller footprint (physical size, power consumption, cooling, and weight)
2. Manageability – Simpler and cheaper systems management
3. Reliability – High availability thanks to redundant components
4. Performance – Improved I/O performance thanks to shared network and storage features
5. Flexibility – Simplified cabling that can be reconfigured in software

© Stephen Foskett for Gestalt IT, 2012. | What Is a Blade Server?
Read more posts categorized as Cloud Computing, Featured, Server Virtualization

A Spectrum of Compatibility

VMware vSphere will run on a wide variety of hardware, so it’s no surprise that vendors feel emboldened to claim compatibility when they shouldn’t. To me, the minimum acceptable level of compatibility is a listing on the official VMware hardware compatibility list (HCL). I would never recommend production use of a product and configuration that is not listed there. “Because I said it works” is not a valid assurance of compatibility.

For more, read I Don’t Care If You Claim It Works (The Support Matrix Blues)

Whenever a vendor claims VMware compatibility, you can bet I am looking it up in the HCL. Time and again, I’ll interrupt a vendor briefing questioning their claims of compatibility. It’s not enough to have product X in the list when you’re pitching product Y! I will accept “we’re working on it” as an answer, but you can bet I’ll check later to see if it ever made the list!

For products that are listed in the VMware HCL, my next question concerns availability of a vCenter plug-in. Although many devices don’t actually need a plug-in, this is typically the next step companies will take when it comes to VMware vSphere. I might actually look upon a product favorably if it doesn’t need a plug-in to function correctly, but it’s definitely best for administrators to be able to configure infrastructure products from within vCenter.

When it comes to block storage products, support for the three main VAAI primitives is a major positive factor. Now that vSphere 5 is here, basic VAAI support is becoming more common. This is because it supports the simpler T10 interfaces for block zeroing, atomic test and set, and extended copy. Once again, any vendor claiming VAAI compatibility gets a quick check in the VMware HCL to find out just what that means. Bonus points for supporting both vSphere 4 and 5.

Check out A Complete List of VMware VAAI Primitives for more info!

I’m really impressed when I come across a storage device that supports advanced VMware integration, NFS such NFS VAAI primitives or VASA. This is really cutting edge stuff at this point, but it won’t be so impressive 6 months from now. By then, I expect more and more companies will support all of VAAI and offer VASA providers. And maybe by then we’ll have more information about what comes next for VMware integration!

True, VMware VASA is Not Much (Yet)

Stephen’s Stance

I’m a storage guy, so my line of questioning revolves around storage integration features. But I encourage everyone to question vendors who claim compatibility with VMware or any other complicated technology. “Because I said so” is not an acceptable answer: We have the right to demand HCL listings, vCenter plug-ins, and advanced API support.

Note: This is the sort of stuff I’ll get into in my “Building Virtual Infrastructure” Seminar Series - Why not sign up and join us? It’s free!

© Stephen Foskett for Gestalt IT, 2012. | “Our Storage Array Is Compatible with VMware…” Says Who?
Read more posts categorized as Server Virtualization, Storage

EMC VFCache is a Simple Read Cache

I was not pre-briefed on this product, and I’m not all that thrilled at the prospect of attending a launch webinar, so what you read here is based on my own research and reading of the available information as of this morning.

When EMC announced Project Lightning last year, company insiders expressed surprise to me. It seems that many had never heard of the project, and those that had didn’t think it was far enough along to be announced. I didn’t even bother to write about the Project Lightning announcement at the time. But today EMC unveils the production product that came out of Project Lightning.

VFCache is a filter driver that caches writes

EMC VFCache appears to be a simple and straightforward offering:

1. A PCIe SSD from Micron or LSI sits in the server and acts as a read cache to accelerate performance
2. EMC software also runs on the server, snooping on I/O and filling the cache with relevant data

There’s not a lot more to the product than that. EMC will sell the PCIe SSD and bundled software as VFCache, and will no doubt market the heck out of this product. Perhaps the only novel twist is the so-called “split-card” mode, which allows the card to act as a write cache. But EMC only supports this for transient “throwaway” data with direct attached storage (DAS) as a backend. There’s no way a conservative, enterprise focused company like EMC would risk sanctioning a writeback cache with no redundancy or data protection features.

VFCache uses a filter driver installed in the VM guest

Perhaps the biggest limitation of the initial VFCache offering is its limited applicability to enterprise server virtualization environments. VFCache uses a filter driver installed in each VM guest, and includes no hypervisor drivers though there is a vCenter plug-in. This makes VMware vMotion very tricky, involving scripting to remove and re-add storage. This means VMware SRM will not easily work, and there is no support for clustering, either.

This is no surprise, since VFCache appears to the host as a local storage volume (AKA, a disk drive or LUN) which would disappear if a virtual machine is moved to another server. Virsto solved this problem by virtualizing storage presentation to the hypervisor, and Fusion-io’s ioTurbine software does not interfere with vMotion either. EMC will likely go in this direction in the future, but it’s a big hole in the product for now.

You might also like reading Micron Bursts Into the PCIe SSD Market to learn more about the card EMC is using

The News: EMC Is in the Host-Based Storage Business

The primary use case for this product is server I/O acceleration. This is desperately needed, as applications and servers are rapidly outrunning the capabilities of conventional storage arrays. EMC and other legacy array manufacturers initially tried to address this I/O imbalance with tiered storage and in array caching. Indeed, these technologies are fairly effective at accelerating the performance of conventional disk storage arrays.

But flash manufacturers like Fusion-io (not to mention Micron and LSI) absolutely demolished storage array performance with their in-server offerings. EMC faced the prospect of losing out on the high-performance storage market. EMC simply could not allow their bread-and-butter enterprise customers to look elsewhere for strategic, high-performance storage for high-profile applications.

VFCache gives EMC salespeople a silver bullet when customers demand maximum performance, but this launch may not spell doom for the flash startups. For one thing, it legitimizes host-based flash cards as a viable component of enterprise storage architectures. It also opens the door to comparison between SAN storage and non–SAN alternatives that go well beyond what EMC is currently offering.

Shared Flash Storage Is on Deck: Project Thunder

“Project Thunder” will externalize the PCIe flash cards over a high-performance “Server Area Network”

As part of the VFCache introduction, EMC is also talking about Project Thunder, a shared version of VFCache. At the very least, thunder will allow multiple servers to access a shared pool of flash cache. This should allow VMware vMotion and DRS to function, and could be much more than that.

EMC could build a high-availability, high-performance all-flash storage array that may even use InfiniBand as an interconnect. The new Nimbus Data E-Class storage array matches this description perfectly, and their CEO tells me that performance over InfiniBand is indeed comparable to in-server PCIe flash cards. It seems logical for EMC to enter this market, if only to disrupt the momentum of Fusion-io and the rest of the all-flash storage upstarts.

Read more about the Nimbus E-Class: The First Big, Redundant, All-Flash Enterprise Array

The only fly in the ointment here is the recent consolidation of the InfiniBand market. Mellanox bought Voltaire, and QLogic sold out to Intel, putting that protocol on tenuous grounds. Perhaps 40 or 100 Gb Ethernet will emerge as a viable alternative for high-performance connectivity, or perhaps these products will retrench on shared PCI Express instead. Micron recently purchased Virtensys for just such a product, and Xsigo has been making big waves in the area of converged I/O as well. The market clearly need something better than Fibre Channel for maximum performance storage, even if InfiniBand isn’t it.

Stephen’s Stance

EMC VFCache (née Project Lightning) is a fairly simple offering: A server-based PCIe flash card that acts as a read cache with no integration with storage arrays or hypervisors. But EMC’s entrance into the host-based flash storage market is a powerful demonstration of the wave of disruption caused by flash-based storage and high-performance computing. Although I am not all that impressed with the product itself, I would be distressed if EMC had not introduced it.

VFCache illustrations are copyright EMC Corporation and are used here with permission

© Stephen Foskett for Gestalt IT, 2012. | EMC VFCache (aka “Project Lightning”) Is One Small Step, But an Important One
Read more posts categorized as Server Virtualization, Storage

I am anxious to get my hands on this file system and play with the features that it will bring to the table.  I do have the Windows 8 preview and will get into it further soon, but from what I have read and previous discussions with Microsoft this seems very very interesting.

Things I like so far:

• Live.  Microsoft is working to engineer ReFS to handle corruption and corrections live, without the need to offline the file system.  This will reduce the time needed to maintain the filesystem.
• Better data integrity as a whole.  Because the file system can manage and mitigate corrupt files and handle much of the repair process online, there will be less need to reboot to take care of maintenance tasks, like following check disk runs.
• Checksums on metadata.  Being able to ensure a file integrity has not been compromised at will without a process run by the user is great.
• Shared Storage Pooling.  This will allow storage across servers to be pooled and shared amongst them creating a load balanced configuration to allow for better resource an file availability.

I cannot say that I am surprised these changes are coming and this makes up for the Metro UI a bit for me, but I do want to see more of that is planned for ReFS and get my hands on it a bit more.  One of these days I will get another Windows laptop and get Windows 8 running on it to get a closer look at the file system and its tools.

For more information on ReFS check out these links:

• http://www.zdnet.com/blog/hardware/microsofts-killer-windows-server-8-feature-refs/17757
• http://www.zdnet.com/blog/microsoft/microsoft-goes-public-with-plans-for-its-new-windows-8-file-system/11666
• http://blogs.msdn.com/b/b8/archive/2012/01/16/building-the-next-generation-file-system-for-windows-refs.aspx

© derek for Gestalt IT, 2012. | ReFS – a new and improved approach
Read more posts categorized as Server Virtualization, Storage

The release you see here today is the first release of the tool that provides log file visualization as well as real-time monitoring of the PCoIP WMI counters.

The PCoIP Log Viewer and the Log Parser can be downloaded from the following website: http://mindfluxinc.net/?p=195 Instructions on how to parse the logs ready for the Viewer should also be available on that link.

Now you have the tool, I guess you’d like to know how to make use of it? As I mentioned, I’ve been using it extensively to help me troubleshoot poor PCoIP performance. To help myself remember and to enable others to understand all of the PCoIP counters better I have put together a PCoIP Troubleshooting page. This should have all of the information you need to make the most out of this brilliant free tool.

© Simon for Gestalt IT, 2012. | PCoIP Log Viewer 2.0
Read more posts categorized as Desktop, Server Virtualization

When designing VDI environments, a couple of things that you should consider are the .vswp file and the GuestOS paging file. In this article I am going to focus on the Paging file and hopefully in the not so distant future I will write a post about the .vswp file in a VDI environment.

What is point of the paging file (also known as the pagefile.sys)?

RAM is a limited resource. Virtual memory was introduced to help remove that limit.

Most modern operating system now use Virtual Memory. Virtual memory is a memory management technique. Applications running on a GuestOS reference memory using virtual memory addresses which are then automatically translated into RAM addresses by the hardware. These virtual memory address spaces are divided in pages or block, usually of 4KB.

If RAM resource is exhusted, the operating system will move 4KB pages of the virtual memory onto the computers hard disk to free up the physical memory (RAM) for other processes. In Windows operating systems, these pages are stored in the pagefile.sys.

A good way to think of this is;

Imagine a restaurant that has just open for the evening. When customers (Processes) arrive they get allocated a table (RAM) to sit and eat at. As the night goes on the restaurant get busier and free tables (RAM) begin to run out for the new customers (Processes) coming through the door. To free up spare tables (RAM) the waiter asks customers (Processes) who have finished eating if they wouldn’t mind moving to the bar (Virtual Memory) where they can continue drink.

Without the paging file, if the physical memory becomes full, applications including the operating system will have to waiting until physical memory becomes available before it can be stored in RAM ready for the CPU to process. As you can imagine this causes massive performance problems.

In summary, you NEED to have a paging file.
Read the rest of this entry »

© Simon for Gestalt IT, 2012. | VDI Paging Files – Big? Small? Or Non At All?
Read more posts categorized as Desktop, Server Virtualization