It’s been awhile since I posted about my home lab, Daisettalabs.net, but rest assured, though I’ve been largely radio silent on it, I’ve been busy.

If 2013 saw the birth of Daisetta Labs.net, 2014 was akin to the terrible twos, with some joy & victories mixed together with teething pains and bruising.

So what’s 2015 shaping up to be?

Well, if I had to characterize it, I’d say it’s #LabGlory, through and through. Honestly. Why?

I’ve assembled a home lab that’s capable of simulating just about anything I run into in the ‘wild’ as a professional. And that’s always been the goal with my lab: practicing technology at home so that I can excel at work.

Let’s have a look at the state of the lab, shall we?

Hardware & Software

Daisetta Labs.net 2015 is comprised of the following:

  • Five (5) physical servers
  • 136 GB RAM
  • Sixteen (16) non-HT Cores
  • One (1) wireless access point
  • One (1) zone-based Firewall
  • Two (2) multilayer gigabit switches
  • One (1) Cable modem in bridge mode
  • Two (2) Public IPs (DHCP)
  • One (1) Silicon Dust HD
  • Ten (10) VLANs
  • Thirteen (13) VMs
  • Five (5) Port-Channels
  • One (1) Windows Media Center PC

That’s quite a bit of kit, as a former British colleague used to say. What’s it all do? Let’s dive in:

Physical Layout

The bulk of my lab gear is in my garage on a wooden workbench.

Nodes 2-4, the core switch, my Zywall edge device, modem, TV tuner, Silicon Dust device and Ooma phone all reside in a secured 12U, two post rack I picked up on ebay about two years ago for $40. One other server, core.daisettalabs.net, sits inside a mid-tower case stuffed with nine 2TB Hitachi HDDs and five 256GB SSDs below the rack.

Placing my lab in the garage has a few benefits, chief among them: I don’t hear (as many) complaints from the family cluster about noise. Also, because it’s largely in the garage, it’s isolated & out of reach of the Child Partition’s curious fingers, which, as every parent knows, are attracted to buttons of all types.

Power & Thermal

Of course you can’t build a lab at home without reliable power, so I’ve got one rack-mounted APC UPS, and one consumer-grade Cyberpower UPS for core.daisettalabs.net and all the internet gear.

On average, the lab gear in the garage consumes about 346 watts, or about 3 amps. That’s significant, no doubt, costing me about $38/month to power, or about 2/3rds the cost of a subscription to IT Pro TV or Pluralsight. 🙂

Thermals are a big challenge. My house was built in 1967, has decent insulation and holds temperature fairly well in the habitable parts of the space. But none of that is true about the garage, where my USB lab thermometer has recorded temps as low as 3C last winter and as high as 39c in Summer 2014. That’s air-temperature at the top of the rack, mind you, not at the CPU.

One of my goals for this year is to automate the shutdown/powerup of all node servers in the Garage based on the temperature reading of the USB thermometer. The $25 thermometer is something I picked up on Amazon awhile ago; it outputs to .csv but I haven’t figured out how to automate its software interface with powershell….yet.

Anyway, here’s my stack, all stickered up and ready for review:

IMG_20150329_214535914

Beyond the garage, the Daisetta Lab extends to my home’s main hallway, the living room, and of course, my home office.

Here’s the layout:

homelab2015

Compute

On the compute side of things, it’s almost all Haswell with the exception of core and node3:

[table]

Server, Architecture, CPU, Cores, RAM, Function, OS, Motherboard

Core, AMD A-series, A8-5500, 2, 8GB, Tiered Storage Spaces & DC/DHCP/DNS, Server 2012 R2, Gigabyte D4

Node1, Haswell, i7-4770k, 4, 32GB, Main PC/Office/VM host/storage, 2012R2, Supermicro X10SAT

Node2, Haswell, Xeon E3-1241, 4, 32GB, Cluster node, 2012r2 core, Supermicro X10SAF

Node3, Ivy Bridge, i7-2600, 4, 32GB, Cluster node, 2012r2 core, Biostar

Node4, Haswell, i5-4670, 4, 32GB, Cluster node/storage, 2012r2 core, Asus

[/table]

I love Haswell for its speed, thermal properties and affordability, but damn! That’s a lot of boxes, isn’t it? Unfortunately, you just can’t get very VM dense when 32GB is the max amount of RAM Haswell E3/i7 chipsets support. I love dynamic RAM on a VM as much as the next guy, but even with Windows core, it’s been hard to squeeze more than 8-10 VMs on a single host. With Hyper-V Containers coming, who knows, maybe that will change?

Node1, the pride of the fleet and my main productivity machine, boasting 2x850 Pro SSDs in RAID 0, an AMD FirePro, and Tiered Storage Spaces
Node1, the pride of the fleet and my main productivity machine, boasting 2×850 Pro SSDs in RAID 0, an AMD FirePro, and Tiered Storage Spaces

While I included it in the diagram, TVPC3 is not really a lab machine. It’s a cheap Ivy Bridge Pentium with 8GB of RAM and 3TB of local storage. It’s sole function in life is to decrypt the HD stream it receives from the Silicon Dust tuner and display HGTV for my mother-in-law with as little friction as possible. Running Windows 8.1 with Media Center, it’s the only PC in the house without battery backup.

Physical Network
About 18 months ago, I poured gallons of sweat equity into cabling my house. I ran at least a dozen CAT-5e cables from the garage to my home office, bedrooms, living room and to some external parts of the house for video surveillance.
I don’t regret it in the least; nothing like having a reliable, physical backbone to connect up your home network/lab environment!

Meet my underlay
Meet my underlay

At the core of the physical network lies my venerable Cisco 2960S-48TS-L switch. Switch1 may be a humble access-layer switch, but in my lab, the 2960S bundles 17 ports into five port channels, serves as my DG, routes with some rudimentary Layer 3 functions ((Up to 16 static routes, no dynamic route features are available)) and segments 9 VLANs and one port-security VLAN, a feature that’s akin to PVLAN.

Switch2 is a 10 port Cisco Small Business SG-300 running at Layer 3 and connected to Switch1 via a 2-port port-channel. I use a few ports on switch2 for the TV and an IP cam.

On the edge is redzed.daisettalabs.net, the Zyxel USG-50, which I wrote about last month.

Connecting this kit up to the internet is my Motorola Surfboard router/modem/switch/AP, which I run in bridge mode. The great thing about this device and my cable service is that for some reason, up to two LAN ports can be active at any given time. This means that CableCo gives me two public, DHCP addresses, simultaneously. One of these goes into a WAN port on the Zyxel, and the other goes into a downed switchport

Love Meraki's RF Spectrum chart!
Love Meraki’s RF Spectrum chart!

Lastly, there’s my Meraki MR-16, an access point a friend and Ubiquity networks fan gave me. Though it’s a bit underpowered for my tastes, I love this device. The MR-16 is trunked to switch1 and connects via an 802.3af power injector. I announce two SSIDs off the Meraki, both secured with WPA2 Personal ((WPA2 Enterprise is on the agenda this year)). Depending on which SSID you connect to, you’ll end up on the Device or VM VLANs.

Virtual Network

The virtual network was built entirely in System Center VMM 2012 R2. Nothing too fancy here, with multiple Gigabit adapters per physical host, one converged logical vSwitch and a separate NIC on each host fronting for the DMZ network:

Nodes 1, 2 & 4 are all Haswell, and are clustered. Node3 is standalone.

Thanks to VMM, building this out is largely a breeze, once you’ve settled on an architecture. I like to run the cmdlets to build the virtual & logical networks myself, but there’s also a great script available that will build a converged network for you.

A physical host typically looks like this (I say typically because I don’t have an equal number of adapters in all hosts):

I trust VLANs and VMM's segmentation abilities, but chose to build what is in effect air-gapped vSwitch for the DMZ/DIA networks
I trust VLANs and VMM’s segmentation abilities, but chose to build what is in effect air-gapped vSwitch for the DMZ/DIA networks

We’re already several levels deep in my personal abstraction cave, why stop here? Here’s the layout of VM Networks, which are distinguished from but related to logical networks in VMM:

labnet13

I get a lot of questions on this blog about jumbo frames and Hyper-V switching, and I just want to reiterate that it’s not that hard to do, and look, here’s proof:

jumbopacket

Good stuff!

Storage

And last, and certainly most-interestingly, we arrive at Daisetta Lab’s storage resources.

My lab journey began with storage testing, in particular ZFS via NexentaCore (Illumos), NAS4Free and Solaris 11. But that’s ancient history; since last summer, I’ve been all Windows, all the time in my lab, starting with SAN.Daisettalabs.net ((cf #StorageGlory : 30 Days on a Windows SAN)).

Now?

Well, I had so much fun -and importantly so few failures/pains- with Microsoft’s Tiered Storage Spaces that I’ve decided to deploy not one, or even two, but three Tiered Storage Spaces. Here’s the layout:

[table]Server, #HDD, #SSD, StoragePool Capacity, StoragePool Free, #vDisks, Function

Core, 9, 6, 16.7TB, 12.7TB, 6 So far, SMB3/iSCSI target for entire lab

Node1,2, 2, 2.05TB, 1.15TB,2, SMB3 target for Hyper-V replication

Node4,3,1, 2.86TB, 1.97TB,2, SMB3 target for Hyper-V replication

[/table]

I have to say, I continue to be very impressed with Tiered Storage Spaces. It’s super-flexible, the cmdlets are well-documented, and Microsoft is iterating on it rapidly. More on the performance of Tiered Storage Spaces in a subsequent post.

Thanks for reading!

Labworks 1:4-7 – The Last Word in ZFS Labworks

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.

Let’s review where we’ve been:

[table]

Labworks Chapter, Verse, Subject, Title & URL

Labworks 1:, 1, Storage, Building a Durable and Performance-Oriented ZFS Box for Hyper-V & VMware

,2-3, StorageI Heart the ARC & Let’s Pull Some Drives!

[/table]

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
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
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:

Lab 1-4-5 - Daisetta Labs

[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

Samsung 830 SSD, 1, 128GB, 512byte, SATA 3, L2ARC Read Cache

Seagate 2.5″ Momentus, 1, 500GB, 512byte, 80MB/r/w, Boot/swap/system

[/table]

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 in excellent Good/Better/Best format
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.

ZIL me

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:

sqlio lab 1 short test

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:

labworks147

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?

storagenetworkingforthewinOn 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

49286241Sr. 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:

sync policy

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:

compressionsync

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 ada0-6 as they struggle under load with the "Always Sync" option enabled.
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.

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:

[table]
Resource, Author, Summary

Nexenta’s awesome whitepapers and guides, Nexenta, Find ’em and collect ’em good stuff on MPIO config and ZFS performance

Comparing SSD vs NoSSD in Nexenta w/NFS, Larry Smith, A fellow ZFS fan with more focus on NFS & VMware

Get the Most out of ZFS SSD, Sebastian “vBagpipes” Laubscher, Sebastian finds a different way to provision the ZIL/SLOG

Nexenta & Scale, Hans DeLeenHeer, Fellow #TFD delegate looks at ZFS tiers in superhero context

SLOG/ZIL Insight, FreeNAS forum, Great forum-focused post on SLOG/ZIL in BSD ZFS

SLOG Blog, Oracle, 2007 post about the ZIL & SLOG heralding storage di

 Zpool and ZIL management, Magnus Strahlert, Excellent how-to guide for ZIL/L2ARC provisioning

[/table]

 

Fail File : SAN down! SAN down! All Nodes respond

Introducing Fail File #1, where I admit to screwing something up and reflect on what I’ve learned

SAN2.daisettalabs.net, the NAS4Free server I built to simulate some of the functions I perform at work with big boy SANs, crashed last night.

Or, to put it another way, I pushed that little AMD-powered, FreeBSD-running, Broadcom-connected, ZFS-flavored franken-array to the breaking point:

Untitled picture
Love the directness of BSD. The iSCSI Target process was killed in cold blood, resulting in the death of several child partitions. What’s more, in just a few words, I have the suspect (Kernel) the motive (swap space) & the victim (iSCSI). Windows would have said, “The service terminated unexpectedly…error 0x081942ad-SOL”

 

Such are the perils of concentrated block storage, amiright? Instantly my Hyper-V Cluster Shared Volumes + the 8 or 9 VMs inside them dropped:

csvs

So what happened here?

I failed to grok the grub or fsck the fdisk or something and gave BSD an inadequate amount of swap space on the root 10GB partition slice. Then I lobbed some iSCSI packets its way from multiple sources and the kernel, starved for resources (because I’m using about 95% of my RAM for the ARC), decided to kill istgt, the iSCSI target service.

Thinking back to the winter, when I ran Nexenta -derived from Sun’s Solaris, not BSD-based- the failure sequence was different, but I’m not sure it was better.

When I was pounding the Nexenta SAN2 back in the winter, volleying 175,000+ iSCSI packets per second its way onto hardware that was even more ghetto, Nexenta did what any good human engineer does: compensate for the operator’s errors & abuses.

It was kind of neat to see. Whether I was running SQLIO simulations, an iometer run, robocopy or eseutil, or just turning on a bunch of VMs simultaneously, one by one, Nexenta services would start to drop as resources were exhausted.

First the gui (NMV it’s called). Then SSH. And finally, sometimes the console itself would lock up (NMC).

But never iSCSI, the disk subsystem, the ARC or L2ARC…those pieces never dropped.

Now to be fair, the GUI, SSH & console services never really turned back on either….you might end up with a durable storage system you couldn’t interact with at all until hard reset, but at least the LUNs stayed online.

This BSD box, in contrast, kills the most important service I’m running on it, but has the courtesy to admit to it and doesn’t make me get up out of my seat: GUI/SSH all other processes are running fine and I’ve instantly identified the problem and will engineer against it.

One model is resilient, bending but not breaking; the other is durable up to a point, and then it just snaps.

Which model is better for a given application?

Fail File Lesson #1: It’s just as important to understand how things fail as it is to understand why they fail, so that you can properly engineer against it. I never thought inadequate swap space would result in a homicidal kernel gunning for the most important service on the box…now I know.

Fresh ZFS on Hyper-V : Nexenta 4.01 CE or I have my evening planned

nexenta4

There’s been some changes in the Daisetta Lab.

Details soon, but sometimes, the fun just can’t wait on my ability to blog it.

Here’s a hint:

  • Nexenta 4.01 Community Edition LIVE
  • 2x Samsung 256GB SSD in RAID 0
  • 3x HGST 2TB in RAID 0
  • Core i5-4670k
  • 16GB RAM on the VM
  • Hyper-V 3.0 & a Legacy virtual NIC because, sadly, Nexenta doesn’t see the Hyper-V Synthetic NIC

The Sammy SSDs put in this outstanding effort last night as I was breaking down into fits of maniacal laughter:

2ssdraid0

1GB/second writes is impressive, but what has ZFS taught us through the course of Labworks 1?

The ARC is still the king.