If you thought -as I admittedly did- that on-prem Windows Server was being left for dead on the side of the Azure road, then boy were we wrong.
Not sure where to start here, but some incredible announcements from Microsoft in Barcelona, most of which I got from Windows Server MVP reporter Aidan Finn
Among them:
VXLAN, NVGRE & Network Controller, courtesy of Azure: This is something I’ve hoped for in the next version of Windows Server: a more compelling SDN story, something more than Network Function Virtualization & NVGRE encapsulation. If bringing the some of the best -and widely supported- bits of the VMware ecosystem to on-prem Hyper-V & System Center isn’t a virtualization engineer’s wet dream, I don’t know what is.
VMware meet Azure Site Recovery: Coming soon to a datacenter near you, failover your VMware infrastructure via Azure Site Recovery, the same way Hyper-V shops can
Not sure what to do with this yet, but gimme!
In-place/rolling upgrades for Hyper-V Clusters: This feature was announced with the release of Windows Server Technical Preview (of course, I only read about it after I wiped out my lab 2012 R2 cluster) but there’s a lot more detail on it from TechEd via Finn: rebuild physical nodes without evicting them first.You keep the same Cluster Name Object, simply live migrating your VMs off your targeted hosts. Killer.
Single cluster node failure: In the old days, I used to lose sleep over clusres.dll, or clussvc.exe, two important pieces in Microsoft Clustering technology. Sure, your VMs will failover & restart on a new host, but that’s no fun. Ben Armstrong demonstrated how vNext handles node failure by killing the cluster service live during his presentation. Finn says the VMs didn’t failover,but the host was isolated by the other nodes and the cluster simply paused and waited for the node to recovery (up to 4 minutes). Awesome!
Azure Witness: Also for clustering fans who are torn (as I am) between selecting file or disk witness for clusters: you will soon be able to add mighty Azure as a witness to your on-prem cluster. Split brain fears no more!
More enhancements for Storage QoS: Ensure that your tenant doesn’t rob IOPS from everyone else.
The Windows SAN, for real: Yes, we can soon do offsite block-level replication from our on-prem Tiered Storage Spaces servers.
New System Center coming next year: So much to unpack here, but I’ll keep it brief. You may love System Center, you may hate it, but it’s not dead. I’m a fan of the big two: VMM, and ConfigMan. OpsMan I’ve had a love/hate relationship with. Well the news out of TechEd Europe is that System Center is still alive, but more integration with Azure + a substantial new release will debut next summer. So the VMM Technical Preview I’m running in the Daisetta Lab (which installs to C:Program FilesVMM 2012 R2 btw) is not the VMM I was looking for.
Other incredible announcements:
Docker, CoreOS & Azure: Integration of the market-leading container technology with Azure is apparently further along than I believed. A demo was shown that hurts my brain to think about: Azure + Docker + CoreOS, the linux OS that has two OS partitions and is fault-tolerant. Wow
Audiocodes announces an on-prem device that appears to bring us one step closer to the dream: Lync for voice, O365 for the PBX, all switched out to the PSTN. I said one step closer!
Azure Operational Insights: I’m a fan of the Splunk model (point your firehose of data/logs/events at a server, and let it make sense of it) and it appears Azure Operational Insights is a product that will jump into that space. Screen cap from Finn
This is really exciting stuff.
Commentary
Looking back on the last few years in Microsoft’s history, one thing stands out: the painful change from the old Server 2008R2 model to the new 2012 model was worth it. All of the things I’ve raved about on this blog in Hyper-V (converged network, storage spaces etc) were just teasers -but also important architectural elements- that made the things we see announced today possible.
The overhaul* of Windows Server is paying huge dividends for Microsoft and for IT pros who can adapt & master it. Exciting times.
* unlike the Windows mobile > Windows Phone transition, which was not worth it
Inhale it boys and girls because what you smell is the sweet aroma of VMware VMs being removed from the vSphere collective and placed into System Center & Hyper-V’s warm embrace.
Microsoft has released version three of its V2V and P2V assimilator tool:
Today we are releasing the Microsoft Virtual Machine Converter (MVMC) 3.0, a supported, freely available solution for converting VMware-based virtual machines and virtual disks to Hyper-V-based virtual machines and virtual hard disks (VHDs).
With the latest release, MVMC 3.0 adds the ability to convert a physical computer running Windows Server 2008 or above, or Windows Vista or above to a virtual machine running on a Hyper-V host (P2V).
This new functionality adds to existing features available including:
• Native Windows PowerShell capability that enables scripting and integration into IT automation workflows.
• Conversion and provisioning of Linux-based guest operating systems from VMware hosts to Hyper-V hosts.
• Conversion of offline virtual machines.
• Conversion of virtual machines from VMware vSphere 5.5, VMware vSphere 5.1, and VMware vSphere 4.1 hosts to Hyper-V virtual machines.
This couldn’t have come at a better time for me. At work -which is keeping me so busy I’ve been neglecting these august pages- my new Hyper-V cluster went Production in mid-September and has been running very well indeed.
But building a durable & performance-oriented virtualization platform for a small to medium enterprise is only 1/10th of the battle.
If I were a consultant, I’d have finished my job weeks ago, saying to the customer:
Right. Here you go lads: your cluster is built, your VMM & SCCM are happy, and the various automation bits ‘n bobs that make life in Modern IT Departments not only bearable, but fun, are complete
But I’m an employee, so much more remains to be done. So among many other things, I now transition from building the base of the stack to moving important workloads to it, namely:
Migrating and/or replacing important physical servers to the new stack
Shepherding dozens of important production VMs out of some legacy ESXi 5 & 4 hosts and into Hyper-V & System Center and thence onto greatness
So it’s really great to see Microsoft release a new version of its tool.
This is a really lame but (IMHO) effective drawing of what I think of as a modern small/medium business enterprise ‘stack’:
As you can see, just about every element of a modern IT is portrayed.
Down at the base of the pyramid, you got your storage. IOPS, RAID, rotational & ssd, snapshots, dedupes, inline compression, site to site storage replication, clones and oh me oh my…all the things we really really love are right here. It’s the Luntastic layer and always will be.
Above that, your compute & Memory. The denser the better, 2U Pizza Boxes don’t grow on trees and the business isn’t going to shell out more $$$ if you get it wrong.
Above that, we have what my networking friends would call the “Underlay network.” Right. Some cat 6, twinax, fiber, whatever. This is where we push some packets, whether to our storage from our compute, northbound out to the world, southbound & down the stack, or east/west across it. Leafs, spines, encapsulation, control & data planes, it’s all here.
And going higher -still in Infrastructure Land mind you- we have the virtualization layer. Yeah baby. This is what it’s all about, this is the layer that saved my career in IT and made things interesting again. This layer is designed to abstract all that is beneath it with two goals in mind: cost savings via efficiency gains & ease of provisioning/use.
And boy,has this layer changed the game, hasn’t it?
So if you’re a virtualization engineer like I am, maybe this is all you care about. I wouldn’t blame you. The infrastructure layer is, after all, the best part of the stack, the only part of the stack that can claim to be #Glorious.
But in my career, I always get roped in (willingly or not) into the upper layers of the stack. And so that is where I shall take you, if you let me.
Next up, the Platform layer. This is the layer where that special DBA in your life likes to live. He optimizes his query plans atop your Infrastructure layer, and though he is old-school in the ways of storage, he’s learned to trust you and your fancy QoS .vhdxs, or your incredibly awesome DRS fault-tolerant vCPUs.
Or maybe you don’t have a DBA in your Valentine’s card rotation. Maybe this is the layer at which the devs in your life, whether they are running Eclipse or Visual Studio, make your life hell. They’re always asking for more x (x= memory, storage, compute, IP), and though they’re highly-technical folks, their eyes kind of glaze over when you bring up NVGRE or VXLAN or Converged/Distributed Switching or whatever tech you heart at the layer below.
Then again, maybe you work in this layer. Maybe you’re responsible for building & maintaining session virtualization tech like RDS or XenApp, or maybe you maintain file shares, web farms, or something else.
Point is, the people at this layer are platform builders. To borrow from the automotive industry, platform guys build the car that travels on the road infrastructure guys build. It does no good for either of us if the road is bumpy or the car isn’t reliable, does it? The user doesn’t distinguish between ‘road’ and ‘car’, do they? They just blame IT.
Next up: software & service layer. Our users exist here, and so do we. Maybe for you this layer is about supporting & deploying Android & iPhone handsets and thinking about MDM. Or maybe you spend your day supporting old-school fat client applications, or pushing them out.
And finally, now we arrive to the top of the pyramid. User-space. The business.
This is where (and the metaphor really fits, doesn’t it?) the rubber meets the road ladies and gentlemen. It’s where the business user drives the car (platform) on the road (infrastructure). This is where we sink or swim, where wins are tallied and heros made, or careers are shattered and the cycle of failure>begets>blame>begets>fear>begets failure begins in earnest.
That’s the stack. And if you’re in IT, you’re in some part of that stack, whether you know it or not.
But the stack is changing. I made a silly graphic for that too. Maybe tomorrow.
Behold, these three remain. File. Block. Object. And the greatest of these is block. – Sr. Systems Engineer St. Paul, in a letter to confused storage engineers in Thessalonika
Right. So a couple weeks back I teased the hardware specs of the new storage array I built for the Daisetta Lab at home.
Software-defined. x86. File and block. Multipath. Intel. And some Supermicro. Storage utopia up in the Daisetta Lab
My idea was to combine all types of disks -rotational 3.5″ & 2.5″ drives, SSDs, mSATAs, hell, I considered USB- into one tight, well-built storage box for my lab and home data needs. A sort of Storage Ark, if you will; all media types were welcome, but only if they came in twos (for mirroring & Parity sake, of course) and only if they rotated at exactly 7200 RPM and/or leveled their wears evenly across the silica.
And onto this unholy motley crue of hard disks I slapped a software architecture that promised to abstract all the typical storage driver, interface, and controller nonsense away, far, far away in fact, to a land where the storage can be mixed, the controllers diverse, and by virtue of the software-definition bits, network & hypervisor agnostic. In short, I wanted to build an agnostic #StorageGlory box in the Daisetta Lab.
Right. So what did I use to achieve this? ZFS and Zpools?
Hell no, that’s so January.
VSAN? Ha! I’m no Chris Wahl.
I used Windows, naturally.
That’s right. Windows. Server 2012 R2 to be specific, running Core + Infrastructure GUI with 8GB of RAM, and some 17TB of raw disk space available to it. And a little technique developed by the ace Microsoft server team called Tiered Storage Spaces.
Was a #StorageGlory Achievement Unlocked, or was it a dud?
Here’s my review after 30 days on my Windows SAN: san.daisettalabs.net.
The Good
It doesn’t make you pick a side in either storage or storage-networking: Do you like abstracted pools of storage, managed entirely by software? Put another way, do you hate your RAID controller and crush on your old-school NetApp filer, which seemingly could do everything but object storage?
When I say block, do you instinctively say file? Or vice-versa?
Well then my friend, have I got a storage system for your lab (and maybe production!) environment: Windows Storage Spaces (now with Tiering!) offers just about everything guys like you or me need in a storage system for lab & home media environments. I love it not just because it’s Microsoft, but also because it doesn’t make me choose between storage & storage-networking paradigms. It’s perhaps the ultimate agnostic storage technology, and I say that as someone who thinks about agnosticism and storage.
A lot.
You know what I’m talking about. Maybe today, you’ll need some block storage for this VM or that particular job. Maybe you’re in a *nix state of mind and want to fiddle with NFS. Or perhaps you’re feeling bold & courageous and decide to try out VMware again, building some datastores on both iSCSI LUNs and NFS shares. Then again, maybe you want to see what SMB 3.0 3.0 is all about, the MS fanboys sure seem to be talking it up.
The point is this: I don’t care what your storage fancy is, but for lab-work (which makes for excellence in work-work) you need a storage platform that’s flexible and supportive of as many technologies as possible and is, hopefully, software-defined.
And that storage system is -hard to believe I’ll grant you- Windows Server 2012 R2.
I love storage and I can’t think of one other storage system -save for maybe NetApp- that let’s me do crazy things like store .vmdks inside of .vhdxs (oh the vIrony!), use SMB 3 multichannel over the same NICs I’m using for iSCSI traffic, create snapshots & clones just like big filers all while giving me the performance-multiplier benefits of SSDs and caching and a reasonable level of resiliency.
File this one under WackWackStorageGloryAchievedWindows boys and girls.
I can do it all with Storage Spaces in 2012 R2.
As I was thinking about how to write about Storage Spaces, I decided to make a chart, if only to help me keep it straight. It’s rough but maybe you’ll find it useful as you think about storage abstraction/virtualization tech:
And yes. Ex post facto dedupe is a made up term. By me. It’s latin for “After the fact, dedupe,” because I always scheduled my dedupes for Saturday night, when the IO load on the filer was low. Ex post facto dedupe is in contrast to some newer storage companies that offer inline compression & dedupe, but none of the ones above offer this, sadly.
It’s easy to build and supports your disks & controllers: This is a Microsoft product. Which means it’s easy to deploy & build for your average server guy. Mine’s running on a very skinny, re-re-purposed SanDisk Ready Cache SSD. With Windows 2012 R2 server running the Infrastructure Management GUI (no explorer.exe, just Server Manager + your favorite snap-ins), it’s using about 6GB of space on the boot drive.
And drivers for the Intel C226 SATA controller, the LSI 9218si SAS card, and the extra ASMedia 1061 controller were all installed automagically by Windows during the build.
The only other system that came close to being this easy to install -as a server product- was Oracle Solaris 11.2 Beta. It found, installed drivers for, and exposed all controllers & disks, so I was well on my way to going the ZFS route again, but figured I’d give Windows a chance this time around.
Nexenta 4, in contrast, never loaded past the Install Community Edition screen.
It’s improved a lot over 2012: Storage Spaces almost two years ago now, and I remember playing with it at work a bit. I found it to be a mind-f*** as it was a radically different approach to storage within the Windows server context.
I also found it to be slow, dreadfully slow even, and not very survivable. Though it did accept any disk disk I gave it, it didn’t exactly like it when I removed a USB drive during an extended write test. And it didn’t take the disk back at the conclusion of the test either.
Like everything else in Microsoft’s current generation, Storage Spaces in 2012 R2 is much better, more configurable, easier to monitor, and more tolerant of disk failures.
It also has something for the IOPS speedfreak inside all of us.
Storage Spaces, abstract this away
Tiered Storage Spaces & Adjustable write cache: Coming from ZFS & the Adaptive Replacement Cache, the ZFS Intent Log, the SLOG, and L2ARC, I was kind of hooked on the idea of using massive amounts of my ECC RAM to function as a sort of poor-mans NVRAM.
Windows can’t do that, but with Tiered Storage Spaces, you can at least drop a few SSDs in your array (in my case three x 256GB 840 EVO & one 128GB Samsung 830), mix them into your disk pool, and voila! Fast read-cache, with a Microsoft-flavored MRU/LFU algorithm of some type keeping your hottest data on the fastest disks and your old data on the cheep ‘n deep rotationals.
What’s more, going with Tiered Storage Spaces gives you a modest 1GB write cache, but as I found out, you can increase that up to 10GB.
Which i naturally did while building this guy out. I mean, who wouldn’t want more write-cache?
But there’s a huge gotcha buried in the Technet and blogposts I found about this. I wanted to pool all my disks together into as large of a single virtual disk as possible, then pack iSCSI-connected .vhdxs, SMB 3 shares, and more inside that single, durable & tiered virtual disk.What I didn’t want was several virtual disks (it helped me to think of virtual disks as a sort of Aggregate) with SMB 3 shares and vhdx files stored haphazardly between them.
Which is what you get when you adjust the write-cache size. Recall that I have a capacity of about 17TB raw among all my disks. Building a storage pool, then a virtual disk with a 10GB write cache gave me a tiered virtual disk with a maximum size of about 965GB. More on that below.
It can be wicked fast, but so is RAID 0: Check out my standard SQLIO benchmark routine, which I run against all storage technologies that come my way. The 1.5 hour test is by no means comprehensive -and I’m not saying the IOPS counter is accurate at all (showing max values across all tests by the way)- but I like this test because it lets me kick the tires on my array, take her out for a spin, and see how she handles.
And with a “Simple” layout (no redundancy, probably equivalent to RAID 0), she handles pretty damn well, but even I’m not crazy enough to run tiered storage spaces in a simple layout config:
These three tests (1.5 hours each, identical setup against multiple configs) were done locally on the array, not over my home network
What’s odd is how poorly the array performed with 10GB of “Write Cache.” Not sure what happened here, but as you can see, latency spiked higher during the 10GB write cache write phase of the test than just about every other test segment.
Something to do with parity no doubt.
For my lab & home storage needs, I settled on a Mirror 2-way parity setup that gives me moderate performance with durability in mind, though not much as you’ll see below.
Making the most of my lab/home network and my NICs: Recall that I have six GbE NICs on this box. Two are built into the Supermicro board itself (Intel), and the other four come by way of a quad-port Intel I350-T4 server NIC.
Anytime you’re planning to do a Microsoft cluster in the 1GbE world, you need lots of NICs. It’s a bit of a crutch in some respects, especially in iSCSI. Typically you VLAN off each iSCSI NIC for your Hyper-V hosts and those NICs do one thing and one thing only: iSCSI, or Live Migration, or CSV etc. Feels wasteful.
But on my new storage box at home, I can use them for double-duty: iSCSI (or LM/CSV) as well as SMB 3. Yes!
Usually I turn off Client for Microsoft Networks (the SMB file sharing toggle in NIC properties) on each dedicated NIC (or vEthernet), but since I want my file cake & my block cake at the same time, I decided to turn SMB on on all iSCSI vEthernet adapters (from the physical & virtual hosts) and leave SMB on the iSCSI NICs on san.daisettalabs.net as well.
The end result? This:
[table caption=”Storage Networking-All of the Above Approach” width=”500″ colwidth=”20|100|50″ colalign=”left|left|center|left|right”]
nic,Name,VLAN,IP,Function
1,MGMT,100,192.168.100.15,MGMT & SMB3
2,CLNT,102,192.168.102.15,Home net & SMB3
3,iSCSI-10,10,172.16.10.x,iSCSI & SMB3
4,iSCSI-11,10,172.16.11.x,iSCSI & SMB3
5,iSCSI-12,10,172.16.12.x,iSCSI & SMB3
[/table]
That’s five, count ’em five NICs (or discrete channels, more specifically) I can use to fully soak in the goodness that is SMB 3 multichannel, with the cost of only a slightly unsettling epistemological question about whether iSCSI NICs are truly iSCSI if they’re doing file storage protocols.
Now SMB 3 is so transparent (on by default) you almost forget that you can configure it, but there’s quite a few ways to adjust file share performance. Aidan Finn argues for constraining SMB 3 to certain NICs, while Jose Barreto details how multichannel works on standalone physical NICs, a pair in a team, and multiple teams of NICs.
I haven’t decided which model to follow (though on san.daisettalabs.net, I’m not going to change anything or use Converged switching…it’s just storage), but SMB 3 is really exciting and it’s great that with Storage Spaces, you can have high performance file & block storage. I’ve hit 420MB/sec on synchronous file copies from san to host and back again. Outstanding!
I Finally got iSNS to work and it’s…meh: One nice thing about san.daisettalabs.net is that that’s all you need to know…the FQDN is now the resident iSCSI Name Server, meaning it’s all I need to set on an MS iSCSI Initiator. It’s a nice feature to have, but probably wasn’t worth the 30 minutes I spent getting it to work (hint: run set-wmiinstance before you run iSNS cmdlets in powershell!) as iSNS isn’t so great when you have…
SMI-S, which is awesome for Virtual Machine Manager fans: SMI-S, you’re thinking, what the the hell is that? Well, it’s a standardized framework for communicating block storage information between your storage array and whatever interface you use to manage & deploy resources on your array. Developed by no less an august body than the Storage Networking Industry Association (SNIA), it’s one of those “standards” that seem like a good idea, but you can’t find it much in the wild as it were. I’ve used SMI-S against a NetApp Filer (in the Classic DoT days, not sure if it works against cDoT) but your Nimbles, your Pures, and other new players in the market get the same funny look on their face when you ask them if they support SMI-S.
“Is that a vCenter thing?” they ask.
Sigh.
Microsoft, to its credit, does. Right on Windows Server. It’s a simple feature you install and two or three powershell commands later, you can point Virtual Machine Manager at it and voila! Provision, delete, resize, and classify iSCSI LUNS on your Windows SAN, just like the big boys do (probably) in Azure, only here, we’re totally enjoying the use of our corpulent.vhdx drives, whereas in Azure, for some reason, they’re still stuck on .vhds like rookies. Haha!
Single Pane o’ glass in VMM with SMI-S, GUIDs galore and more for the Hyper-V set
It’s a very stable storage platform for Microsoft Clustering: I’ve built a lot of Microsoft Hyper-V clusters. A lot. More than half a dozen in production, and probably three times that in dev or lab environments, so it’s like second nature to me. Stable storage & networking are not just important factors in Microsoft clusters, they are the only factors.
So how is it building out a Hyper-V cluster atop a Windows SAN? It’s the same, and different at the same time, but, unlike so many other cluster builds, I passed the validation test on the first attempt with green check marks everywhere. And weeks have gone by without a single error in the Failover Clustering snap-in; it’s great.
The Bad
It’s expensive and seemingly not as redundant as other storage tech: When you build your storage pool out of offlined disks, your first choice is going to involve (just like other storage abstraction platforms) disk redundancy. Microsoft makes it simple, but doesn’t really tell you the cost of that redundancy until later in the process.
Recall that I have 17TB of raw storage on san.daisettalabs.net, organized as follows:
[table]
Disk Type, Quantity, Size, Format, Speed, Function
WD Red 2.5″ with NASWARE, 6, 1TB, 4KB AF, SATA 3 5400RPM, Cheep ‘n deep
Samsung 840 EVO SSD, 3, 256GB, 512byte, 250MB/read, Tiers not fears
Samsung 830 SSD, 1, 128GB, 512byte, 250MB/read, Tiers not fears
HGST 3.5″ Momentus, 6, 2TB, 512byte, 105MB/r/w, Cheep ‘n deep
[/table]
Now, according to my trusty IOPS Excel calculator, if I were to use traditional RAID 5 or RAID 6 on that set of spinners, I’d get about 16.5TB usable in the former, 15TB usable in the latter (assuming RAID penalty of 5 & 6, respectively)
For much of the last year, I’ve been using ZFS & RAIDZ2 on the set of six WD Red 2.5″ drives. Those have a raw capacity of 6TB. In RAIDZ2 (roughly analogous to RAID 6), I recall getting about 4.2TB usable.
All in all, traditional RAID & ZFS’ RAIDZ cost me between 12% and 35% of my capacity respectively.
So how much does Windows Storage Spaces resiliency model (Mirrored, 2-way parity) cost me? A lot. We’re in RAID-DP territory here people:
Ack! With 17TB of raw storage, I get about 5.7TB usable, a cost of about 66%!
And for that, what kind of resieliency do I get?
I sure as hell can’t pull two disks simultaneously, as I did live during prod in my ZFS box. I can suffer the loss of only a single disk. And even then, other Windows bloggers point to some pain as the array tries to adjust.
Now, I’m not the brightest on RAID & parity and such, so perhaps there’s a more resilient, less costly way to use Storage Spaces with Tiering, but wow…this strikes me as a lot of wasted disk.
Not as easy to de-abstract the storage: When a disk array is under load, one of my favorite things to do is watch how the IO hits the physical elements in the array. Modern disk arrays make what your disks are doing abstract, almost invisible, but to truly understand how these things work, sometimes you just want the modern equivalent of lun stats.
In ZFS, I loved just letting gstat run, which showed me the load my IO was placing on the ARC, the L2ARC and finally, the disks. Awesome stuff:
In this Gifcam, watch ada0-6 as they struggle under load with the “Always Sync” option enabled.
As best as I can tell, there’s no live powershell equivalent to gstat for Storage Spaces. There are teases though; you can query your disks, get their SMART vitals, and more, but peeling away the onion layers and actually watching how Windows handles your IO would make Storage Spaces the total package.
Bottom line
So that’s about it: this is the best storage box I’ve built in the Daisetta Lab. No regrets going with Windows. The platform is mature, stable, offers very good performance, and decent resiliency, if at a high disk cost.
I’m so impressed I’ve checked my Windows SAN skepticism at the door and would run this in a production environment at a small/medium business (clustered, in the Scaled Out File Server role). Cost-wise, it’s a bargain. Check out this array: it’s the same exact Hardware a certain upstart Storage vendor I like (that rhymes with Gymbal Porridge) sells, but for a lot less!
Stick figure man wants his application to run faster. #WhiteboardGlory courtesy of VM Turbo’s Yuri Rabover
So you may recall that back in March, yours truly, Parent Partition, was invited as a delegate to a Tech Field Day event, specifically Virtualization Field Day #3, put on by the excellent team at Gestalt IT especially for the guys guys who like V.
And you may recall further that as I diligently blogged the news and views to you, that by day 3, I was getting tired and grumpy. Wear leveling algorithms intended to prevent failure could no longer cope with all this random tech field day IO, hot spots were beginning to show in the parent partition and the resource exhaustion section of the Windows event viewer, well, she was blinking red.
And so, into this pity-party I was throwing for myself walked a Russian named Yuri, a Dr. named Schmuel and a product called a “VMTurbo” as well as a Macbook that like all Mac products, wouldn’t play nice with the projector.
You can and should read all about what happened next because 1) VMTurbo is an interesting product and I worked hard on the piece, and 2) it’s one of the most popular posts on my little blog.
Now the great thing about VMTurbo OpsMan & Yuri & Dr. Schmuel’s presentation wasn’t just that it played into my fevered fantasies of being a virtualization economics czar (though it did), or that it promised to bridge the divide via reporting between Infrastructure guys like me and the CFO & corner office finance people (though it can), or that it had lots of cool graphs, sliders, knobs and other GUI candy (though it does).
No, the great thing about VMTurbo OpsMan & Yuri & Dr. Schmuel’s presentation was that they said it would work with that other great Type 1 Hypervisor, a Type-1 Hypervisor I’m rather fond of: Microsoft’s Hyper-V.
I didn’t even make screenshots for this review, so suffer through the annotated .pngs from VMTurbo’s website and imagine it’s my stack
And so in the last four or five weeks of my employment with Previous Employer (PE), I had the opportunity to test these claims, not in a lab environment, but against the stack I had built, cared for, upgraded, and worried about for four years.
That’s right baby. I put VMTurbo’s economics engine up against my six node Hyper-V cluster in PE’s primary datacenter, a rationalized but aging cluster with two iSCSI storage arrays, a 6509E, and 70+ virtual machines.
Who’s the better engineer? Me, or the Boston appliance designed by a Russian named Yuri and a Dr. named Schmuel?
Here’s what I found.
The Good
Thinking economically isn’t just part of the pitch: VMTurbo’s sales reps, sales engineers and product managers, several of whom I spoke with during the implementation, really believe this stuff. Just about everyone I worked with stood up to my barrage of excited-but-serious questioning and could speak literately to VMTurbo’s producer/consumer model, this resource-buys-from-that-resource idea, the virtualized datacenter as a market analogy. The company even sends out Adam Smith-themed emails (Famous economist…wrote the Wealth of Nations if you’re not aware). If your infrastructure and budget are similar to what mine were at PE, if you stress over managing virtualization infrastructure, if you fold paper again and again like I did, VMTurbo gets you.
Installation of the appliance was easy: Install process was simple: download a zipped .vhd (not .vhdx), either deploy it via VMM template or put the VHD into a CSV and import it, connnect it to your VM network, and start it up. The appliance was hassle-free as a VM; it’s running Suse Linux, and quite a bit of java code from what I could tell, but for you, it’s packaged up into a nice http:// site, and all you have to do is pop in the 30 day license XML key.
It was insightful, peering into the stack from top to nearly the bottom and delivering solid APM: After I got the product working, I immediately made the VMturbo guys help me designate a total of about 10 virtual machines, two executables, the SQL instances supporting those .exes and more resources as Mission Critical. The applications & the terminal services VMs they run on are pounded 24 hours a day, six days a week by 200-300 users. Telling VMTurbo to adjust its recommendations in light of this application infrastructure wasn’t simple, but it wasn’t very difficult either. That I finally got something to view the stack in this way put a bounce in my step and a feather in my cap in the closing days of my time with PE. With VMTurbo, my former colleagues on the help desk could answer “Why is it slow?!?!” and I think that’s great.
Like mom, it points out flaws, records your mistakes and even puts a $$ on them, which was embarrassing yet illuminating: I was measured by this appliance and found wanting. VMTurbo, after watching the stack for a good two weeks, surprisingly told me I had overprovisioned -by two- virtual CPUs on a secondary SQL server. It recommended I turn off that SQL box (yes, yes, we in Hyper-V land can’t hot-unplug vCPU yet, Save it VMware fans!) and subtract two virtual CPUs. It even (and I didn’t have time to figure out how it calculated this) said my over-provisioning cost about $1200. Yikes.
It’s agent-less: And the Windows guys reading this just breathed a sigh of relief. But hold your golf clap…there’s color around this from a Hyper-V perspective I’ll get into below. For now, know this: VMTurbo knocked my socks off with its superb grasp & use of WMI. I love Windows Management Instrumentation, but VMTurbo takes WMI to a level I hadn’t thought of, querying the stack frequently, aggregating and massaging the results, and spitting out its models. This thing takes WMI and does real math against the results, math and pivots even an Excel jockey could appreciate. One of the VMTurbo product managers I worked with told me that they’d like to use Powershell, but powershell queries were still to slow whereas WMI could be queried rapidly.
It produces great reports I could never quite build in SCOM: By the end of day two, I had PDFs on CPU, Storage & network bandwidth consumption, top consumers, projections, and a good sense of current state vs desired state. Of course you can automate report creation and deliver via email etc. In the old days it was hard to get simple reports on CSV space free/space used; VMTurbo needed no special configuration to see how much space was left in a CSV
vFeng Shui for your virtual datacenter
Integrates with AD: Expected. No surprises.
It’s low impact: I gave the VM 3 CPU and 16GB of RAM. The .vhd was about 30 gigabytes. Unlike SCOM, no worries here about the Observer Effect (always loved it when SCOM & its disk-intensive SQL back-end would report high load on a LUN that, you guessed it, was attached to the SCOM VM).
A Eureka! style moment: A software developer I showed the product to immediately got the concept. Viewing infrastructure as a supply chain, the heat map showing current state and desired state, these were things immediately familiar to him, and as he builds software products for PE, I considered that good insight. VMTurbo may not be your traditional operations manager, but it can assist you in translating your infrastructure into terms & concepts the business understands intuitively.
I was comfortable with its recommendations: During #VFD3, there was some animated discussion around flipping the VMTurbo switch from a “Hey! Virtualization engineer, you should do this,” to a “VMTurbo Optimize Automagically!” mode. But after watching it for a few weeks, after putting the APM together, I watched its recommendations closely. Didn’t flip the switch but it’s there. And that’s cool.
You can set it against your employer’s month end schedule: Didn’t catch a lot of how to do this, but you can give VMTurbo context. If it’s the end of the month, maybe you’ll see increased utilization of your finance systems. You can model peaks and troughs in the business cycle and (I think) it will adjust recommendations accordingly ahead of time.
Cost: Getting sensitive here but I will say this: it wasn’t outrageous. It hit the budget we had. Cost is by socket. It was a doable figure. Purchase is up to my PE, but I think VMTurbo worked well for PE’s particular infrastructure and circumstances.
The Bad:
No sugar coating it here, this thing’s built for VMware: All vendors please take note. If VMware, nomenclature is “vCPU, vMem, vNIC, Datastore, vMotion” If Hyper-V, nomenclature is “VM CPU, VM Mem, VMNic, Cluster Shared Volume (or CSV), Live Migration.” Should be simple enough to change or give us 29%ers a toggle. Still works, but annoying to see Datastore everywhere.
Interface is all flash: It’s like Adobe barfed all over the user interface. Mostly hassle-free, but occasionally a change you expected to register on screen took a manual refresh to become visible. Minor complaint.
Doesn’t speak SMB 3.0 yet: A conversation with one product engineer more or less took the route it usually takes. “SMB 3? You mean CIFS?” Sigh. But not enough to scuttle the product for Hyper-V shops…yet. If they still don’t know what SMB 3 is in two years…well I do declare I’d be highly offended. For now, if they want to take Hyper-V seriously as their website says they do, VMTurbo should focus some dev efforts on SMB 3 as it’s a transformative file storage tech, a few steps beyond what NFS can do. EMC called it the future of storage!
Didn’t talk to my storage: There is visibility down to the platter from an APM perspective, but this wasn’t in scope for the trial we engaged in. Our filer had direct support, our Nimble, as a newer storage platform, did not. So IOPS weren’t part of the APM calculations, though free/used space was.
The Ugly:
Trusted Install & taking ownership of reg keys is required: So remember how I said VMTurbo was agent-less, using WMI in an ingenious way to gather its data from VMs and hosts alike? Well, yeah, about that. For Hyper-V and Windows shops who are at all current (2012 or R2, as well as 2008 R2), this means provisioning a service account with sufficient permissions, taking ownership of two Reg keys away from Trusted Installer (a very important ‘user’) in HKLMCLSID and one further down in WOW64, and assigning full control permissions to the service account on the reg key. This was painful for me, no doubt, and I hesitated for a good week. In the end, Trusted Installer still keeps full-control, so it’s a benign change, and I think payoff is worth it. A Senior VMTurbo product engineer told me VMTurbo is working with Microsoft to query WMI without making the customer modify the registry, but as of now, this is required. And the Group Policy I built to do this for me didn’t work entirely. On 2008 R2 VMs, you only have to modify the one CLSID key
Soup to nuts, I left PE pretty impressed with VMTurbo. I’m not joking when I say it probably could optimize my former virtualized environment better than I could. And it can do it around the clock, unlike me, even when I’m jacked up on 5 Hour Energy or a triple-shot espresso with house music on in the background.
Stepping back and thinking of the concept here and divesting myself from the pain of install in a Hyper-V context: products like this are the future of IT. VMTurbo is awesome and unique in an on-prem context as it bridges the gap between cost & operations, but it’s also kind of a window into our future as IT pros
That’s because if your employer is cloud-focused at all, the infrastructure-as-market-economy model is going to be in your future, like it or not. Cloud compute/storage/network, to a large extent, is all about supply, demand, consumption, production and bursting of resources against your OpEx budget.
What’s neat about VMTurbo is not just that it’s going to help you get the most out of the CapEx you spent on your gear, but also that it helps you shift your thinking a bit, away from up/down, latency, and login times to a rationalized economic model you’ll need in the years ahead.
Greetings to you Labworks readers, consumers, and conversationalists. Welcome to the last verse of Labworks Chapter 1, which has been all about building a durable and performance-oriented ZFS storage array for Hyper-V and/or VMware.
Today we’re going to circle back to the very end of Labworks 1:1, where I assigned myself some homework: find out why my writes suck so bad. We’re going to talk about a man named ZIL and his sidekick the SLOG and then we’re going to check out some Excel charts and finish by considering ZFS’ sync models.
But first, some housekeeping: SAN2, the ZFS box, has undergone minor modification. You can find the current array setup below. Also, I have a new switch in the Daisetta Lab, and as switching is intimately tied to storage networking & performance, it’s important I detail a little bit about it.
Labworks 1:4 – Small Business SG300 vs Catalyst 2960S
Cisco’s SG-300 & SG-500 series switches are getting some pretty good reviews, especially in a home lab context. I’ve got an SG-300 and really like it as it offers a solid spectrum of switching options at Layer 2 as well as a nice Layer 3-lite mode all for a tick under $200. It even has a real web-interface if your CLI-shy, which
Small Business Cisco != Linksys
I’m not but some folks are.
Sadly for me & the Daisetta Lab, I need more ports than my little SG-300 has to offer. So I’ve removed it from my rack and swapped it for a 2960S-48TS-L from the office, but not just any 2960S.
No, I have spiritual & emotional ties to this 2960s, this exact one. It’s the same 2960s I used in my January storage bakeoff of a Nimble array, the same 2960s on which I broke my Hyper-V & VMware cherry in those painful early days of virtualization, yes, this five year old switch is now in my lab:
The pride of Cisco’s 2009 Desktop Switching series, the 2960s
Sure it’s not a storage switch, in fact it’s meant for IDFs and end-users and if the guys on that great storage networking podcast from a few weeks back knew I was using this as a storage switch, I’d be finished in this industry for good.
But I love this switch and I’m glad its at the top of my rack. I saved 1U, the energy costs of this switch vs two smaller ones are probably a wash, and though I lost Layer 3 Lite, I gained so much more: 48 x 1GbE ports and full LAN-licensed Cisco IOS v 15.2, which, agnostic computing goals aside for a moment, just feels so right and so good.
And with the increased amount of full-featured switch ports available to me, I’ve now got LACP teams of three on agnostic_node_1 & 2, jumbo frames from end to end, and the same VLAN layout.
Here’s the updated Labworks schematic and the disk layout for SAN2:
[table]
Disk Type, Quantity, Size, Format, Speed, Function
WD Red 2.5″ with NASWARE, 6, 1TB, 4KB AF, SATA 3 5400RPM, Zpool Members
Samsung 840 EVO SSD, 1, 128GB, 512byte, SATA 3, L2ARC Read Cache
Labworks 1:5 – A Man named ZIL and his sidekick, the SLOG
Labworks 1:1 was all about building durable & performance-oriented storage for Hyper-V & VMware. And one of the unresolved questions I aimed to solve out of that post was my poor write performance.
Review the hardware table and you’ll feel like I felt. I got me some SSD and some RAM, I provisioned a ZIL so write-cache that inbound IO already ZFS, amiright? Show me the IOPSMoney Jerry!
Well, about that. I mischaracterized the ZIL and I apologize to readers for the error. Let’s just get this out of the way: The ZFS Intent Log (ZIL) is not a write-cache device as I implied in Labworks 1:1.
ZFS storage layout in excellent Good/Better/Best format courtesy of Nexenta, which has some outstanding documentation & guides
The ZIL, whether spread out among your rotational disks by ZFS design, or applied to a Separate Log Device (a SLOG), is simply a synchronous writes mechanism, a log designed to ensure data integrity and report (IO ACK) back to the application layer that writes are safe somewhere on your rotational media. The ZIL & SLOG are also a disaster recovery mechanisms/devices ; in the event of power-loss, the ZIL, or the ZIL functioning on a SLOG device, will ensure that the writes it logged prior to the event are written to your spinners when your disks are back online.
Now there seem to be some differences in how the various implementations of ZFS look at the ZIL/SLOG mechanism.
Nexenta Community Edition, based off Illumos which is the open source descendant of Sun’s Solaris, says your SLOG should just be a write-optimized SSD, but even that’s more best practice than hard & fast requirement. Nexenta touts the ZIL/SLOG as a performance multiplier, and their excellent documentation has helpful charts and graphics reinforcing that.
In contrast, the most popular FreeBSD ZFS implementations documentation paints the ZIL as likely more trouble than its worth. FreeNAS actively discourages you from provisioning a SLOG unless it’s enterprise-grade, accurately pointing out that the ZIL & a SLOG device aren’t write-cache and probably won’t make your writes faster anyway, unless you’re NFS-focused (which I’m proudly, defiantly even, not) or operating a large database at scale.
What’s to account for the difference in documentation & best practice guides? I’m not sure; some of it’s probably related to *BSD vs Illumos implementations of ZFS, some of it’s probably related to different audiences & users of the free tier of these storage systems.
The question for us here is this: Will you benefit from provisioning a SLOG device if you build a ZFS box for Hyper-V and VMWare storage for iSCSI?
I hate sounding like a waffling storage VAR here, but I will: it depends. I’ve run both Nexenta and NAS4Free; when I ran Nexenta, I saw my SLOG being used during random & synchronous write operations. In NAS4Free, the SSD I had dedicated as a SLOG never showed any activity in zfs-stats, gstat or any other IO disk tool I could find.
One could spend weeks of valuable lab time verifying under which conditions a dedicated SLOG device adds performance to your storage array, but I decided to cut bait. Check out some of the links at the bottom for more color on this, but in the meantime, let me leave you with this advice: if you have $80 to spend on your FreeBSD-based ZFS storage, buy an extra 8GB of RAM rather than a tiny, used SLC or MLC device to function as your SLOG. You will almost certainly get more performance out of a larger ARC than by dedicating a disk as your SLOG.
Labworks 1:6 – Great…so, again, why do my writes suck?
Recall this SQLIO test from Labworks 1:1:
As you can see, read or write, I was hitting a wall at around 235-240 megabytes per second during much of “Short Test”, which is pretty close to the theoretical limit of an LACP team with two GigE NICs.
But as I said above, we don’t have that limit anymore. Whereas there were once 2x1GbE Teams, there are now 3x1GbE. Let’s see what the same test on the same 4KB block/4KB NTFS volume yields now.
SQLIO short test, take two, sort by Random vs Sequential writes & reads:
By jove, what’s going on here? This graph was built off the same SQLIO recipe, but looks completely different than Labworks 1. For one, the writes look much better, and reads look much worse. Yet step back and the patterns are largely the same.
It’s data like this that makes benchmarking, validating & ultimately purchasing storage so tricky. Some would argue with my reliance on SQLIO and those arguments have merit, but I feel SQLIO, which is easy to script/run and automate, can give you some valuable hints into the characteristics of an array you’re considering.
Let’s look at the writes question specifically.
Am I really writing 350MB/s to SAN2?
On the one hand, everything I’m looking at says YES: I am a Storage God and I have achieved #StorageGlory inside the humble Daisetta Lab HQ on consumer-level hardware:
SAN2 is showing about 115MB/s to each Broadcom interface during the 32KB & 64KB samples
Agnostic_Node_1 perfmon shows about the same amount of traffic eggressing the three vEthernet adapters
The 2960S is reflecting all that traffic; I’m definitely pushing about 350 megabytes per second to SAN2; interface port channel 3 shows TX load at 219 out of 255 and maxing out my LACP team
On the other hand, I am just an IT Mortal and something bothers:
CPU is very high on SAN2 during the 32KB & 64KB runs…so busy it seems like the little AMD CPU is responsible for some of the good performance marks
While I’m a fan of the itsy-bitsy 2.5″ Western Digitial RED 1TB drives in SAN2, under no theoretical IOPS model is it likely that six of them, in RAIDZ-2 (RAID 6 equivalent) can achieve 5,000-10,000 IOPS under traditional storage principles. Each drive by itself is capable of only 75-90 IOPS
If something is too good to be true, it probably is
Sr. Storage Engineer Neo feels really frustrated at this point; he can’t figure out why his writes suck, or even if they suck, and so he wanders up to the Oracle to get her take on the situation and comes across this strange Buddha Storage kid.
Labworks 1:7 – The Essence of ZFS & New Storage model
In effect, what we see here is is just a sample of the technology & techniques that have been disrupting the storage market for several years now: compression & caching multiply performance of storage systems beyond what they should be capable of, in certain scenarios.
As the chart above shows, the test2 volume is compressed by SAN2 using lzjb. On top of that, we’ve got the ZFS ARC, L2ARC, and the ZIL in the mix. And then, to make things even more complicated, we have some sync policies ZFS allows us to toggle. They look like this:
The sync toggle documentation is out there and you should understand it it is crucial to understanding ZFS, but I want to demonstrate the choices as well.
I’ve got three choices + the compression options. Which one of these combinations is going to give me the best performance & durability for my Hyper-V VMs?
SQLIO Short Test Runs 3-6, all PivotTabled up for your enjoyment and ease of digestion:
As is usually the case in storage, IT, and hell, life in general, there are no free lunches here people. This graph tells you what you already know in your heart: the safest storage policy in ZFS-land (Always Sync, that is to say, commit writes to the rotationals post haste as if it was the last day on earth) is also the slowest. Nearly 20 seconds of latency as I force ZFS to commit everything I send it immediately (vs flush it later), which it struggles to do at a measly average speed of 4.4 megabytes/second.
Compression-wise, I thought I’d see a big difference between the various compression schemes, but I don’t. Lzgb, lz4, and the ultra-space-saving/high-cpu-cost gzip-9 all turn in about equal results from an IOPS & performance perspective. It’s almost a wash, really, and that’s likely because of the predictable nature of the IO SQLIO is generating.
Labworks 1:Epilogue
Last point: ZFS, as Chris Wahl pointed out, is a sort of virtualization layer atop your storage. Now if you’re a virtualization guy like me or Wahl, that’s easy to grasp; Windows 2012 R2’s Storage Spaces concept is similar in function.
But sometimes in virtualization, it’s good to peel away the abstraction onion and watch what that looks like in practice. ZFS has a number of tools and monitors that look at your Zpool IO, but to really see how ZFS works, I advise you to run gstat. GStat shows what your disks are doing and if you’re carefully setting up your environment, you ought to be able to see the effects of your settings on each individual spindle.
In this Gifcam, watch ada0-5 (the western digitals)as they struggle under load with the “Always Sync” option enabled. Notice that the zvol/Alpha-Pool/Test2 volume (The logical volume construct) is at 100% busy and the ops/s are not very stellar.
Now look at this gstat sample. Under SQLIO-load, the zvol is showing 10,000 IOPS, 300+MB/s. But ada0-5, the physical drives, aren’t doing squat for several seconds at a time as SAN2 absorbs & processes all the IO coming at it.
That, friends, is the essence of ZFS.
Links/Knowledge/Required Reading Used in this Post:
Hello Labworks fans, detractors and partisans alike, hope you had a nice Easter / Resurrection / Agnostic Spring Celebration weekend.
Last time on Labworks 2:1-4, we looked at some of the awesome teaming options Microsoft gave us with Server 2012 via its multiplexor driver. We also made the required configuration adjustments on our switch for jumbo frames & VLAN trunking, then we built ourselves some port channel interfaces flavored with LACP.
I think the multiplexor driver/protocol is one of the great (unsung?) enhancements of Server 2012/R2 because it’s a sort of pre-virtualization abstraction layer (That is to say, your NICs are abstracted & standardized via this driver before we build our important virtual switches) and because it’s a value & performance multiplier you can use on just about any modern NIC, from the humble RealTek to the Mighty Intel Server 10GbE.
But I’m getting too excited here; let’s get back to the curriculum and get started shall we?
Goals
5. Understand what Microsoft’s multiplexor driver/LBFO has done to our NICs
6. Build our Virtual Machine Switch for maximum flexibility & performance
7. The vEthernets are Coming
8. Next Steps: Jumbo frames from End-to-end and performance tuning
Schematic:
2:5 Understand what Microsoft’s Multiplexor driver/LBFO has done to our NICs
So as I said above, the best way to think about the multiplexor driver & Microsoft’s Load Balancing/Failover tech is by viewing it as a pre-virtualization abstraction layer for your NICs. Let’s take a look.
Our Network Connections screen doesn’t look much different yet, save for one new decked-out icon labeled “Daisetta-Team:”
Meanwhile, this screen is still showing the four NICs we joined into a team in Labworks 2:3, so what gives?
A click on the properties of any of those NICs (save for the RealTek) reveals what’s happened:
Egads! My Intel NIC has been neutered by LBFO
The LBFO process unbinds many (though not all) settings, configurations, protocols and certain driver elements from your physical NICs, then binds the fabulous Multiplexor driver/protocol to the NIC as you see in the screenshot above.
In the dark days of 2008 R2 & Windows core, when we had to walk up hill to school both ways in the snow I had to download and run a cmd tool called nvspbind to get this kind of information.
Fortunately for us in 2012 & R2, we have some simple cmdlets:
So notice Microsoft has essentially stripped “Ethernet 4” of all that would have made it special & unique amongst my 4x1GbE NICs; where I might have thought to tag a VLAN onto that Intel GbE, the multiplexor has stripped that option out. If I had statically assigned an IP address to this interface, TCP/IP v4 & v6 are now no longer bound to the NIC itself and thus are incapable of having an IP address.
And the awesome thing is you can do this across NICs, even NICs made by separate vendors. I could, for example, mix the sacred NICs (Intel) with the profane NICs (RealTek)…it don’t matter, all NICs are invited to the LBFO party.
No extra licensing costs here either; if you own a Server 2012 or 2012 R2 license, you get this for free, which is all kinds of kick ass as this bit of tech has allowed me in many situations to delay hardware spend. Why go for 10GbE NICs & Switches when I can combine some old Broadcom NICs, leverage LACP on the switch, and build 6×1 or 8x1GbE Converged LACP teams?
LBFO even adds up all the NICs you’ve given it and teases you with a calculated LinkSpeed figure, which we’re going to hold it to in the next step:
4GbS LACP team sounds great, but is it really 4Gb/s?
2:6 Build our Virtual Machine Switch for maximum flexibility & performance
If we just had the multiplexor protocol & LBFO available to us, it’d be great for physical server performance & durability. But if you’re deploying Hyper-V, you get to have your LBFO cake and eat it too, by putting a virtual switch atop the team.
This is all very easy to do in Hyper-V manager. Simply right click your server, select Virtual Switch Manager, make sure the Multiplexor driver is selected as the NIC, and press OK.
Bob’s your Uncle:
But let’s go a bit deeper and do this via powershell, where we get some extra options & control:
New-vmswitch : the cmdlet we’re invoking to build the switch. Run get-help new-vmswitch for a rundown of the cmdlet’s structure & options
-NetAdapterInterfaceDescription : here we’re telling Windows which NIC to build the VM Switch on top of. Get the precise name from Get-NetAdapter and enclose it in quotes
-Allow ManagementOS 1 : Recall the diagram above. This boolean switch (1 yes, 0 no) tells Windows to create the VM Switch & plug the Host/Management Operating System into said Switch. You may or may not want this; in the lab I say yes; at work I’ve used No.
-Minimum Bandwidth Mode Weight: We lay out the rules for how the switch will apportion some of the 4Gb/s bandwidth available to it. By using “Weight,” we’re telling the switch we’ll assign some values later
Name: Name your switch
A few seconds later, and congrats Mr. Hyper-V admin, you have built a converged virtual switch!
2:7 The vEthernets are Coming
Now that we’ve built our converged virtual switch, we need to plug some things into it. And that starts on the physical host.
If you’re building a Hyper-V cluster or stand-alone Hyper-V host with VMs on networked storage, you’ll approach vEthernet adpaters differently than if you’re building Hyper-V for VMs on attached/internal storage or on SMB 3.0 share storage. In the former, you’re going to need storage vEthernet adpters; in the latter you won’t need as many vEthernets unless you’re going multi-channel SMB 3.0, which we’ll cover in another labworks session.
I’m going to show you the iSCSI + Failover Clustering model.
In traditional Microsoft Failover Clustering for Virtual Machines, we need a minimum of five discrete networks. Here’s how that shakes out in the Daisetta Lab:
[table]
Network Name, VLAN ID, Purpose, Notes
Management, 1, Host & VM management network, You can separate the two if you like
CSV, 14, Host Cluster & communication and coordination, Important for clustering Hyper-V hosts
LM, 15, Live Migration network, When you must send VMs from broke host to host with the most LM is there for you
iSCSI 1-3, 11-13, Storage, Soemwhat controversial but supported
[/table]
Now you should be connecting that dots: remember in Labworks 2:1, we built a trunked port-channel on our Cisco 2960S for the sole purpose of these vEthernet adapters & our converged switch.
So, we’re going to attach tagged vethernet adapters to our host via powershell. Pay attention here to the “-managementOS” tag; though our Converged switch is for virtual machines, we’re using it for our physical host as well.
You can script his out of course (and VMM does that for you), but if you just want to copy paste, do it in this order:
Notice we didn’t include a Gateway in the New-NetIPAddress cmdlet; that’s because when we built our Virtual Switch with the “-managementOS 1” switch attached, Windows automatically provisioned a vEthernet adapter for us, which either got an IP via DHCP or took an apipa address.
So now we have our vEthernets and their appropriate VLAN tags:
Ignore the DMZ vEthernet for now. Notice Daisetta-Converged, our VM Switch, is seen as a VMNetworkAdapter and is untagged. In my lab, this interface functions as my Host Management interface. In a production scenario, you’ll probably use separate vEthernet adapters for Host Management and not expose the switch itself to the management OS
2:8: Next Steps : Jumbo Frames from end-to-end & Performance Tuning
So if you’ve made it this far, congrats. If you do nothing else, you now have a converged Hyper-V virtual switch, tagged vEthernets on your host, and a virtualized infrastructure that’s ready for VMs.
But there’s more you can do; stay tuned for the next labworks post where we’ll get into jumbo frames & performance tuning this baby so she can run with all the bandwidth we’ve given her.
Links/Knowledge/Required Reading Used in this Post:
[table]
Resource, Author, Summary New-VMSwitch Technet, Microsoft, Always good to have Technet reference Building a Converged Fabric with Server 2012, Hans “The Hyper-Dutchman” Vredevoort, A 2012 post which helped me when I was struggling through 2008 R2 to 2012 Hyper-V migration
Aidan Finn, upstanding Irishman, apparent bear-cub puncher, hobbyist photog, MVP all-star and one of my favorite Hyper-V bloggers (seriously, he’s good, and along with DidierV & the Hyper-Dutchman has probably saved my vAss more times than I can vCount) appeared on one of my favorite podcasts last week, RunAs Radio with Canuck Richard Campbell.
Which is all sorts of awesome as these are a few of my favorite things piled on top of each other (Finn on RunAs).
The subject? Hyper-V, scale out file servers (SoFS) in 2012 R2, SMB 3.0 multichannel and Microsoft storage networking, which are just about my favoritest subjects in the whole wide world. I mean what are the odds that one of my favorite Hyper-V bloggers would appear on one of my favorite tech podcasts? Remote. And talk about storage networking tech, Redmond-style, during that podcast?
Where Perfmon is king, you will find Hyper-V bloggers like DidierV, who gets to play with 10G RDMA NICs
All that and an adorable Irish brogue?
This is Instant nerdgasm territory here people; if you’re into these black arts as I am, it’s a must-listen.
Anyway, Finn reminded me of his famous powershell demos in which he demonstrates all the options we Hyper-V admins have at our disposal now when it comes to Live Migrating VMs from host to host.
And believe me, we have so many now it’s almost embarrassing, especially if you cut your teeth on Hyper-V 2.0 in 2008 R2, where successfully Live Migrating VMs off a host (or draining one during production) involved a few right clicks, chicken sacrifice, Earth-Jupiter-Moon alignment, a reliable Geiger counter by your side and a tolerance for Pucker Factor Values greater than 10* **.
Nowadays, we can:
Live Migrate VMs between hosts in a cluster (.vhdx parked in a Cluster Shared Volume, VM config, RAM & CPU on a host….block storage, the Coke Classic option)
Live Migrate VMs parked on SMB 3.0 shares, just like you NFS jockeys do
Shared-nothing Live Migration, either storage + VM, just storage, or just VM!
A for instance: from my Dell Latitude i7 ultrabook with Windows 8.1 and client hyper-v installed (natch), I can storage Live Migrate a .vhdx off my skinny but fast 256GB SSD to a spacious SMB share at work, then drop it back on my laptop at the end of the day, all via Scheduled Task or powershell with no downtime for the VM
With Server 2012/2012 R2 you get all those options + SMB 3.0 multichannel
Not only that, but we have some cool new toys with which to make the cost of Live Migration a VM to the host with the most a little less painful:
Standard TCP/IP : I like this because I’m old school and anything that stresses the network and LACP is fun because it makes the network guy sweat
Compression: Borrow spare cycles from the host CPU, compress the VM’s RAM, and Live Migrate your way out of a tight spot
SMB via Remote Direct Memory Access : the holy of holies in Live Migration. As Finn points out, this bit of tech can scale beyond the bandwidth capabilities of the PCIe 3 bus. SMB 3.0 + RDMA makes you hate your Northbridge
Finn*** of course provided some Live Migration start:finish times resulting from the various methods above, which I then, of course, interpreted as Finn daring me personally over the radio to try and beat those times in my humble Daisetta Lab.
Now this is just for fun people; not a Labworks-style list of repeatable results, so let’s not nerd-out on how my testing methodology isn’t sound & I’m a stupidhead, ok?
Anyway, Sysinternals has a nice little tool to redline the RAM in your Windows VM. I don’t know how Finn does it, but I don’t have workloads (yet!) in the Lab that would fill 4GB of RAM with non-random data on a VM, so off to the cmd we go:
You type this (haven’t played with all the switches yet) in this navy blue screen:
And then this happen and the somewhat pink graph goes full pink:
Then we press this button to test Live Migration w/ compression, as the Daisetta Lab doesn’t have fancy RDMA NICs like certain well-connected Irish Hyper-V bloggers:
Wish I had some RDMA NICs :sadface:
Which makes this bluecelestedenim Azure colored line get all spikey:
Oh! My NUMA! Second spike somewhat higher than first. Why?
all of which results in a wicked-fast Live Migrations & really cool orange-colored charts in my totally non-random, non-scientific but highly enjoyable laboratory experiment
Still, in the end, I like my TCP/IP uncompressed Live Migrations because 1) sackcloth & ashes, and 2) I didn’t go to the trouble of building a multiplexed LACP team -with a virtual switch on top!- just to let the Cat5es in my attic have an easy day at the office:
But at work: yes. I love this compression stuff and echo Finn’s observations on how Hyper-V doesn’t slam your host CPUs beyond what the host & its VM fleet could bear.
Anyway, did I beat Finn’s Live Migration times in this fun little test? Will the Irish MVP have to admit he’s not so esteemed after all and surrender his Hyper_V_MVP_badge.gif to me?
Of course I did and yes he will.
But not really.
[table caption=”Daisetta Lab LM vs Finn’s Powershell LM Scripts – 4GB VM” width=”500″ colwidth=”20|100|50″ colalign=”left|left|left|left|left”]
Who,TCP/IP LM,Compressed LM,RDMA & SMB 3 LM,Notes
Finn,78 seconds, 15 seconds,6.8 seconds, “Mr. I once moved a VM with 56GB of RAM in 35 seconds probably has a few Xeons”
D-Lab,38 seconds,Like 12 or something,Who’s ass do I need to kiss to get RDMA/iWarp?, But seriously my VM RAM was probably not random
[/table]
Finn notes in his posts that he’s dedicating an entire 1GbE NIC for his Live Migration Demos, wheras I’m embracing the converged switch model and haven’t even played with bandwidth or QOS settings on my Hyper-V switch.
How do my VMware colleagues & friends measure this stuff & think about vMotion performance & reliability? I know NFS can scale & perform, but am ignorant on the nuances of v3 vs v4, how it works on the host and Distributed vSwitch and your “Shared nothing” storage vMotion. And what’s this I hear that vSphere won’t begin a vMotion without knowing it will complete? How’s that determined?
I mean I could spend an hour or two googling it, or you could, I don’t know, post a comment and save me the time and spread some of your knowledge 😀
I’m jazzed about SMB 3.0, but there are only a handful of storage vendors who have support for the new stack, and among them, as Finn points out, Microsoft is #1 storage vendor for SMB 3 fans, with NetApp probably in 2nd place.
* Just kidding, it wasn’t that bad. Most days.
** Pucker Factor Value can be measured by querying obscure wmi class win32_pfv
*** Finn is a consultant. So you can hire him. I have no relationship with him other than admiration for his scripting skillz
Greetings Labworks fans, today we’re going to learn how to build converged Hyper-V switches, switches so cool they’re nearly identical to the ones available to enterprise users with their fancy System Center licenses.
If you’re coming from a VMware mindset, a Hyper-V converged switch is probably most similar to Distributed vSwitches, though admittedly I’m a total n00b on VMware, so take that statement with a grain of salt. The idea here is to build an advanced switching fabric on your Hyper-V hosts that is fault-tolerant & performance-oriented, and like a Distributed vSwitch, common among your physical hosts and your guests.
This is one of my favorite topics because I have a serious & problematic love-affair with LACP and a Terrets-like urge to team things up & jumbo, but you don’t need an LACP-capable switch or jumbo frame to enjoy Converged Switching goodness.
Let’s dive in, shall we?
Goals
Prepare the physical switch for Jumbo Frames
Understand LBFO: Microsoft’s Load Balancing/Fail Over teaming technology introduced in Server 2012
Enable LACP on the Switch and on the Server
Build the Switch on the Team & Next Steps
Required Tools ‘n Tech:
Server 2012 or 2012 R2…sorry Windows 8.1 Professional/Enterprise fans…LBFO is not available for 8.1. I know, I feel your pain. But the naked Hyper-V 3.0 Hypervisor (Core only) is free, so what are you waiting for?
A switch, preferably gigabit. LACP not required but a huge performance multiplier
NICs: As in plural. You need at least two. Yes, you can use your Keepin’ it RealTek NICs..Hyper-V doesn’t care that your NICs aren’t server-grade, but I advise against consumer-NICs for production!!
Schematic
State of the Lab as of today. Ag_node_1 is new, with a core i7 Haswell (Yay!), ag_node_2 is the same, still running CSVs off my ZFS box, and check it out, bottom right: a new host, SMB1:
SMB1 Detail:
2:1 Prepare the Physical Switch for Jumbo Frames
You can skip this section if all you have at your disposal is a dumb switch.
Commands below are off of a Cisco 2960s. Commands are similar on the new SG300 & 500 series Cisco switches. PowerConnect 5548 switches from Dell aren’t terribly different either, though I seem to recall you have you enable jumbo mtu on each port as well as the switch.
First we’re going to want to turn on Jumbo Frames, system-wide, which usually requires a reload of your switch, so schedule for a maintenance window!
daisettalabs.net(config)#system mtu jumbo 9198
You can run a show system mtu after the reload to be sure the switch is ready for the corpulent frames you will soon send its way:
daisettalabs.net#show system mtu
System MTU size is 1514 bytes
System Jumbo MTU size is 9198 bytes
System Alternate MTU size is 1514 bytes
Routing MTU size is 1514 bytes
2:2 Load Balancing & Failover
Load Balancing & Failover, or LBFO as it’s known, was the #1 feature I was looking forward to in Server 2012.
And boy did Microsoft deliver.
LBFO is a driver/framework that takes whatever NICs you have, “teams” them, applies a mature & resilient multiplexor driver to them, and gives you redundancy & performance in just a few clicks or powershell cmdlets. Let’s do GUI for the team, and later on, we’ll use Powershell to build a switch on that team.
Sidenote: Don’t bother applying IP addresses, VLANs to your LBFO-destined physical NICs at this point. Do bother installing your manufacturer’s latest driver, or hacking one on as I’ve had to do with my new ag_node_1 Intel NIC. (SideSideNote: as this blogger states, Intel can eat a bag of d**** for dropping so many NICs from Server 2012 support. Broadcom, for all the hassles I’ve had with them, still updates drivers on four year old cards!)
On SMB1 from the above schematic, I’ve got five gigabit NICs. One is a RealTek on the motherboard, and the other four are Intel; 1-4 on a PCIe Quad Gigabit network card, i350 x4 I believe.
The RealTek NIC has a static IP and is my management interface for the purposes of this labworks. We’ll only be teaming the four Intel NICs here. Be sure to leave at least one of your NICs out of the LBFO team unless you are sitting in front of your server console; you can always add it in later.
Launch Server Manager in the GUI and click on “All Servers,” then right click on SMB1 and select Configure NIC Teaming:
A new window will emerge,titled, NIC Teaming.
In the NIC Teaming window, notice on the right the five GbE adapters you have and their status (Green Arrow). Click on “Tasks” and select “New Team” (Red Arrow):
The New Team window is where all the magic happens. Let’s pause for a moment and go to our switch.
On my old 2960s, we’re building LACP-flavored port channels by using the “channel group _ mode active” command, which tells the switch to use the genuine-article LACP/802.11ax protocol rather than the older Cisco proprietary Port Aggregation Protocol (PAgp) system, which is activated by running “channel group _ mode auto.”
However, if you have a newer switch, perhaps a nice little SG 300 or something similar, PAgp is dead and not available to you, but the process for LACP is like the old PAgp command: “channel group _ mode auto” will turn on LACP.
Here’s the 2960s process. Note that my Intel NICs are plugged into Gig 1/0/20-23, with spanning-tree portfast enabled (which we’ll change once our Converged virtual switch is built):
daisettalabs.net#show run int gig 1/0/20
Building configuration...
Current configuration : 63 bytes
!
interface GigabitEthernet1/0/20
spanning-tree portfast
daisettalabs.net#conf t
Enter configuration commands, one per line. End with CNTL/Z.
daisettalabs.net(config)#int range gig 1/0/20-23
daisettalabs.net(config-if-range)#description SMB1 TEAM
daisettalabs.net(config-if-range)#speed 1000
daisettalabs.net(config-if-range)#duplex full
daisettalabs.net(config-if-range)#channel-group 3 mode active
daisettalabs.net(config-if-range)#switchport mode trunk
daisettalabs.net(config-if-range)#
daisettalabs.net(config-if-range)#do wr
Building configuration...
[OK]
Presto! That wasn’t so hard was it?
Note that I’ve trunked all four interfaces; that’s important in Hyper-V Converged switching. We’ll need to trunk po3 as well.
Let’s take a look at our new port channel:
daisettalabs.net(config-if-range)#do show run int po3
Building configuration…
Current configuration : 54 bytes
!
interface Port-channel3
switchport mode trunk
end
daisettalabs.net(config-if-range)#
Now let’s check the state of the port channel:
daisettalabs.net#show etherchannel summary
Flags: D - down P - bundled in port-channel
I - stand-alone s - suspended
H - Hot-standby (LACP only)
R - Layer3 S - Layer2
U - in use f - failed to allocate aggregator
M - not in use, minimum links not met u - unsuitable for bundling w - waiting to be aggregated d - default port Number of channel-groups in use: 3 Number of aggregators: 3 Group Port-channel Protocol Ports ------+-------------+-----------+-----------------------------------------------
1 Po1(SU) LACP Gi1/0/1(P) Gi1/0/2(P) Gi1/0/3(P)
2 Po2(SU) LACP Gi1/0/11(D) Gi1/0/13(P) Gi1/0/14(P) Gi1/0/15(P) Gi1/0/16(P)
3 Po3(SD) LACP Gi1/0/19(s) Gi1/0/20(D) Gi1/0/21(s) Gi1/0/22(s) Gi1/0/23(D)
po3 is in total disarray, but not for long. Back on SMB1, it’s time to team those NICs:
I’m a fan of naming-conventions even if this screenshot doesn’t show it; All teams on all hosts have the same “Daisetta-Team” name, and I usually rename NICs as well, but honestly, you could go mad trying to understand why Windows names NICs the way it does (Seriously. It’s a Thing). There’s no /dev/eth0 for us in MIcroosft-land, it’s always something obscure and strange and out-of-sequence, which is part of the reason why Converged Switching & LBFO kick ass; who cares what your interfaces are named so long as they are identically configured?
If you don’t have an LACP-capable switch, you’ll select “Switch Independent” here.
As for Load Balancing modes: in server 2012, you get Address Hash (Source/Dest MAC or IP in Layer 3 LACP), or Hyper-V Port, which is sort of a round-robin approach (VM1 goes to one port in the team, VM2 to the other).
I prefer the new (with 2012 R2) Dynamic mode which negotiates with the physical switch. More color on those choices & what they mean for you in the References section at the bottom.
Press ok, sit back, and watch my gifcam shot:
Mmmm, taste the convergence.
2:4 Build a Switch on top of that team & Next Steps
If you’ve ever built a switch for Hyper-V, you’ll find building the converged switch immediately familiar, save for one technicality: you’re going to build a switch on top of that multiplexor driver you just created!
Sounds scary? Perhaps. I’ll go into some of the intricacies and gotchas and show some cool powershell bits ‘n bobs on the next episode of Labworks.
Eventually we’re going to dangle all sorts of things off this virtual switch-atop-a-multiplexor-driver!
Links/Knowledge/Required Reading Used in this Post:
[table]
Resource, Author, Summary Windows Server 2012 LBFO Whitepaper, Microsoft, Must-have though a bit dated at this point Etherchannel Considerations, Jeremy Stretch at Packetlife.net, Great overview on Cisco aggregation tech including LACP and PAgp
I’ve been going on, insufferably at times, about my new Nimble storage array at work. Back in January, it passed my home-grown bakeoff with flying colors, in February I wrote about how it was inbound to my datacenter, in March I fretted over iSCSI traffic, .vhdx parades, and my 6509-E.
Well it’s been just about a month since it was racked up and jacked into my Hyper-V fabric and I thought maybe the storage nerds among my readers would like an update on how its performing.
The Good
Fast: It’s been strange getting compliments, kudos and thank yous rather than complaints and ALL CAPS emails punctuated by Exclamation Marks. I have a couple of very critical SQL databases, the performance of which can make or break my job, and after some deliberation, we took the risk and moved the biggest of them to the Nimble about three weeks ago.
Here’s a slightly edited email from one power user 72 hours later:
Did I say THANK YOU for the extra zip yet?
STILL LOVING IT!!
I’m taken aback by all the affection coming my way…no longer under user-siege, I feel like maybe I should dress better at work, shave every day, turn on some lights in the office perhaps. Even the dev team was shocked, with one of them invoking Spaceballs and saying his storage-dependent process was moving at “Ludicrous speed.”
It’s Easy: I can’t underscore this enough. If you’re a mid-sized enterprise with vanilla/commodity workloads and you can tolerate an array that’s just iSCSI (you can still use NFS or SMB 3, just from inside clustered VMs!), Nimble’s a good fit, especially if your staff is more generalist in nature. or you don’t have time to engineer a new SAN from scratch.
This was a Do It Yourself storage project for me; I didn’t have the luxury or time to hire storage engineers or VARs to come in and engineer it for me. Nimble will try to sell you on professional services, but you can decline and hook it up yourself, as I did. There are best practice guides a-plenty, and if you understand your stack & workload, your switching & compute, you’ll do fine.
Buying it was easy: Nimble’s lineup is simple and from a customer standpoint, it was a radically different experience to buy a Nimble than a traditional SAN.
Purchasing a big SAN is like trying to decide what to eat at French restaurant in Chinatown…you recognize the letters and & the pictures on the menu look familiar, but you don’t know what that SKU is exactly or how you’ll feel in the morning after buying & eating it. And while the restaurant has provided a helpful & knowledgeable garçon to explain French cuisine & etiquette to you, you know the garçon & his assistants moonlight at the Italian, German and Sushi place down the road, where they are equally knowledgeable & enthusiastic about those cuisines. But they can’t talk about the Italian place because they have something called agency with the french restaurant; so with you, they are only French cuisine experts, and their professional opinion is that Italian, German and Sushi are horrible food choices. Also, your spend with the restaurant is too small to get the chef’s attention..you have to go through this obnoxious garçon system.
Buying from Nimble, meanwhile, is like picking a burger at In ‘n Out. You have three options, all of them containing meat, and from left to right, the choices are simply Good, Better, Best. You can stack shelves onto controller-shelves, just like a Double-Double, and you know what you’ll get in the end. Oh sure, there’s probably an Animal Style option somewhere, but you don’t need Animal Style to enjoy In ‘n Out, do you?
Lesson is this: Maybe your organization needs a real full-featured SAN & VAR-expertise. But maybe you just need fast, reliable iSCSI that you can hook up yourself.
It’s nice that we in customer-land have that option now.
ASUP & Community: The Autosupport from Nimble has left nothing to be desired, in fact, I think they nag too much. But I’ll take that over a downed array.
I’ve grown to enjoy Connect.Nimble.com, the company’s forum where guys like me can compare notes. Shout out to one awesome Nimble SE named Adam Herbert who built a perfect signed MPIO Powershell script that maps your initiators to your targets in no time at all.
And then you get to sit back and watch as MPIO does its thang across all your iSCSI HBAs, producing symmetrical & balanced utilization charts which, in turn, release pleasing little bursts of storage-dopamine in your brain.
It works fine with Hyper-V, CSVs, and Converged Fabric vEthernets: What a mouthful, but it’s true. Zero issues fitting this array into System Center Virtual Machine Manager storage (though it doesn’t have SMI-S support a “standard” which few seem to have adopted), failing CSVs from one Hyper-V node to another, and resizing CSVs or RDMs live.
Taking a big bite out of Storage Network’s forbidden fruit: LACP + MPIO
And for the convergence fans: I pretty much lost my fear of using vEthernet adapters for iSCSI traffic during the bakeoff and in the Daisetta Lab at home, but in case you needed further convincing that Hyper-V’s converged fabric architecture kicks ass, here it is: Each Hyper-V node in my datacenter has 12 gigabit NICs. Eight of them per host are teamed (that is to say they get the Microsoft Multiplexor driver treatment, LACP-flavor) and then a Converged Virtual switch is built atop the multiplexor driver. From that converged v-switch, I’m dangling six virtual Ethernet adapters per host, two of which, are tagged for the Nimble VLAN I built in the 6509.
That’s a really long and complicated way of saying that in a modest-sized production environment, I’m using LACP teaming on the hosts, up to 4x1GbE vNics on the VIP guests, and MPIO to the storage, which conventional storage networking wisdom says is a bit like kissing your sister and bragging about it. Maybe it’s harmless (even enjoyable?) once or twice, but sooner or later, you’ll live to regret it. And hey the Department of Redundancy Department called, they want one of their protocols back.
I’ve read a lot of thoughtful pieces from VMware engineers & colleagues about doing this, but from a Hyper-V perspective,this is supported, and from a Nimble array perspective, I’m sure they’d point the finger at this if something went wrong, but it hasn’t, and from my perspective : one converged virtual switch = easy to deploy/templatize, easy to manage & monitor. Case closed.
LACP + MPIO in Hyper-V works so well that in three weeks of recording iSCSI stats, I’ve yet to record a single TCP error/re-transmit or anything that would make me think the old model was better. And I haven’t even applied bandwidth policies on the converged switches yet; that tool is still in my box and right now iSCSI is getting the Hyper-V equivalent of best effort.
It’s getting faster: Caching is legit. All my monitors and measurements prove it out. Implement your Nimble correctly, and you may see it get faster as time goes on.
And by that I mean don’t tick the “caching” box for every volume. Conserve your resources, develop a strategy and watch it bloom and grow as your iSCSI packets find their way home faster and faster.
The DBA is noticing it too in his latency timers & long running query measurements, but this graph suffices to show caching in action over three weeks in a more exciting way than a select * from slow-ass-tables query:
Up is good. We like up because it means fewer trips to the rotationals*.
Least Frequently Used, Most Recently Used, Most Frequently Used….who frequently/recently cares what caching algorithm the CASL architecture is using? A thousand whiteboard sessions conducted by the world’s greatest SE with the world’s greatest schwag gifts couldn’t sell me on this the way my own charts and my precious perfmons do.
My cached Nimble volumes are getting faster baby.
Compression wise, I’m seeing some things I didn’t expect. Some volumes are compressing up to 40x. Others are barely hitting 1.2x. The performance impact of this is hard to quantify, but from a conservation standpoint, I’m not having to grow volumes very often. It’s a wash with the old dedupe model, save for one thing: I don’t have to schedule compression. That’s the CPUs job, and for all I know, the Nehalems inside my CS260 are, or should be, redlining as they lz4 my furious iSCSI traffic.
The Bad
Busy Box & CLI: The Nimble command line in version 1.4x felt familiar to me the first time I used it. I recognized the command structure, the help files and more, and thought it looked like Busy Box.
Hey wait a minute. Where’s my breakfast confection CLI? This looks like….ANDROID
What’s Busy Box? How to put this without making enemies of The Guys Who Say Vi…Busy Box is a collection of packages, tools, servers and scripts for the unix world developed about 25 years ago by an amazing Unix engineer. It’s very popular, it’s everywhere, and it’s reliable and I have no complaints about it other than the fact that it’s disconcerting that my Nimble has the same package of tools I once installed on my Android handset.
But that’s just the Windows guy talking, a Windows guy who was really fond of his WAFL and misses it but will adapt and holds out hope that OneGet & PowerShell, one day, will emerge victorious over all.
The Ugly
The SSL cert situation is embarrassing and I’m glad my former boss hasn’t seen it. Namely that situation is this: you can’t replace the stock SSL cert, which, frankly looks like something I would do while tooling around with OpenSSL in the lab.
Who is Jetty Mortbay and why does he want inside my root CA store?
I understand this is fixed in the new 2.x OS version but holy shit what a fail.
Other than that, I’m very pleased -and the organization is very pleased***- with our Nimble array.
It feels like at last, I’m enjoying the fruits of my labor, I’m riding a high-performance storage array that was cost-effective, easy to install, and is performing at/above expectations. I’m like Major Kong, my array is literally the bomb, man and his machine are in harmony and there’s some joy & euphoria up in the datacenter as my task is complete.
*Remember this lesson #StorageGlory seekers: no one knows your workload like you. The above screenshot of cache hits is of a 400GB SQL transaction log volume of a larger SQL DB that’s in use 24/6. Your mileage may vary.
*** I do not speak for the organization even though I just did.
Wilson.tech 
