(Server) Virtualization

I could be classified as an enthusiast. There is a 42U rack standing in my utility room. Before i had two servers humming away, using around 400W. One of those servers is my router/firewall/web-server. The other a file-server with.. uhm... stuff...
Because i keep them running 24/7 (they are servers right?), i wanted to look into server virtualization to save some power.
Now i'm running a single server, using 158W, running ESXi 3.5. Because the machine i'm using is a little slow, i am looking into new hardware. I found it very hard to find any good, up to date information about what hardware would work with what kind of hypervisor.

ESX and XenServer can be used for free now. There are a couple of limitations but that's not a problem for home use. I started thinking that maybe more people here on bit-tech are in the same situation.
So i wondered if there could be an article or something on Virtualization in general and more specific, server virtualization. It would be good to have a good reference about what is available and what hardware you need to make use of it.

Ideally it could be a (small) part of the buyer's guide, with a small list of hardware best suited for virtualization. But i guess it's hard enough too get that list

For others reading this post wanting to look in to virtualization, here are a some sites with information. But as i said, it's a bit out-dated and about ESX only sadly.

http://www.vm-help.com/esx40i/esx40_whitebox_HCL.php

http://ultimatewhitebox.com/

Thanks in advance

 

Hi there. I know a bit about server virtualization. I run 32 x Dell PE2950 ESX 4 hosts running approx 400 VM's for my employer. I designed and implemented the whole virtualised server estate.

On the VMware website there is a whole VMware Community Hardware/Software section detailing hardware that's not on the VMware HCL but community members have successfully used it their ESX hosts. Details stuff that won't work also. If you search on the VMware forums for whitebox you'll find loads of info.

Community Hardware/Software Forum

Have a look at Citrix Xen Server also. It's pretty good.

 

Excellent suggestion.

I am building my first real server myself and would like to have some virtualization. A guide to some different hypervisors would be great.

There might even be more members like scott_chegg who knows about these things. Perhabs one of these members would be willing to write a article, or a forum-sticky?

 

I am getting a 50/50 mbit fiber connection here soon. (hooray for the Netherlands )
I've already got the hardware picked out for my new server. I'm hoping it can run both ESX(i) and XenServer (not at the same time offcourse).

I'll keep my fingers crossed...

Maybe the article will be there in time

 

ESX/ESXi is a bare-metal (type 1) hypervisor, whereas (although I've not used it), XenServer appears to be a hosted (type 2) hypervisor.

They are not directly comparable therefore, as they will do key things differently, including the hosted OS requiring a license if you use Windows for example!

I've been using ESX / ESXi since 2.0 on and off for the past 3/4 years, as there's quite a bit of crossover in storage and network connectivity with my network engineer role, so while I am useless at writing articles etc I'm more than happy to give specific advice, if there's a thread somewhere about it.

If you want to run multiple Linux/BSD servers on a single machine I'd usually recommend ESX4.0i as its free and requires no hosted OS license in the first place.

 

There are 2 versions of Xen. The Xen Hypervisor is type 1. Installed directly onto the tin. HXen is the hosted type 2 currently in dev by the look of it. Much like VMwares ESX (type 1) and VMware Server (type 2).

Type 1 is installed directly onto the hardware and can be managed using client apps on windows or linux or directly via a linux like console or ssh session. If your not afraid of a bit of linux work these give you the best performance as the hardware doesn't have to run a fully blown OS as well as the VM's.

Type 2 is hosted. You install a OS (windows or linux) then you install the virtualization software, known as a VMM (Virtual Machine Monitor) as an app. You've got the additional strain of a fully blown OS on the tin in this scenario.

ESX and ESXi are type 1. ESX has a service console which is a costomised linux instance. This allows you to manage the VMKernel (the actual heart of ESX) in a linux like environment. ESXi doesn't have a service console so is much smaller alowing it to be run from usb pen drives and even CF cards mounted directly to the server mobo. ESXi can be managed via a helper linux VM available from VMware. Both can be managed via a windows client app that's downloadable from your ESX or ESXi installation via a web interface. ESXi is free and ESX with it's service console will be dropped in the next release.

Xen Hypervisor is a similar affair. Installed directly on the tin and managed via an app.

Microsoft have Hyper-V. They sell it as a type 1 but it's arguable whether it is truly a type 1. You install Windows Server 2008 R2 and enable the Hyper-V role. The 2008 installation on the box then becomes the parent partition allows you to create VM's and run them. You still have to manage the parent 2008 installation and put up with the RAM requirements it uses. Not free as you need to have a 2008 R2 license. Good for SMB's who don't have any linux skills and want to consolidate a few few servers down.

For the enthusiast at home I would always say go for ESXi. If you've got a bit of hardware that'll run it and you want to learn a bit of linux it's great . Check the link I previously posted for what hardware will run it.

I'll keep this thread in my subscription list and try to answer anyone's questions if your having a go.

Cheers

 

Sweet. Thankyou very much!
+rep

 

Cheers for clearing up the type of XenServer. Haven't needed to evaluate it yet, so wasn't sure, but the way the website was talking it seemed to indicate it was an application you installed onto an OS.

I was recently involved in a lab between ESX/ESXi and Hyper-V. Hyper-V's support for teamed NICs at the same time as multiple VLANs is better than Virtual Server 2005 (which was rubbish) but is still woefully inadequate in comparison to ESX's networking stack. The fact you've gotta license the base OS is a pain too, unless of course you use a single Datacentre license, in which case you get unlimited Standard virtuals on it!

 

Having read loads and loads up on a home based vmware estate this is what i would recommend for approximatly 5-10 VM's.

CPU - Q6600

Memory - 8GB -12 GB of Memory (you will run out of memory long before you run out of CPU cycles)

Storage Adapter (Depending on Budget and RAID Level Wanted) but anything from adaptec or LSI should be fine - Or look into using your old server as a iSCSI box via open filler

Motherboard - Gigabyte EP35-DS4 (dont used onboard RAID controller) but can generally be had cheap and works well.

NIC - 1 or 2 x Intel 1000GT PCI

These specs will work fine. The RAID controller normally poses the biggest issues with home brew ESXi boxes if im been honest which is why if your budget allows i'd get a proper one from LSI or adaptec (The Adaptec RAID 2045 is also VMWare certified also), but the open filer option i suggested although more complicated will make good use of old hardware and disc's via iscsi.

On the other hand, you could get a ML110 G6 with a entry level Xeon on it for around £350 inc VAT at the moment and these make ideal, low power boxes. How ever the kit i suggested above will be more powerful and long term cheaper to upgrade.

Phil

 

Thanx for the info PHILIP, but I've got some other hardware picked out already. I'm on a very tight budget, so a RAID controller is out of the question for me. Even the memory has to suffer. But i'm taking into account future upgrade-ability.

According to my research this should work (at least with ESXi 4.0 and i'm betting XenServer)

Motherboard: ASUS M4A785T-M
CPU: AMD Athlon II X4 635, 2,9Ghz
Memory: Kingston 2 x 2GB, DDR3, 1333Mhz (will upgrade later)

Not sure when i'm going to order this stuff. I will let you guys know when i'm up and running

 

ESXi is fussy about network controllers.
Check the onboard controller is on the (unofficial) HCL

 

Generally ESX/i requires a hardware based NIC, and a hardware based RAID controller, if you're using RAID anyway. Onboard Intel NICs are in my experience sometimes okay ... but as is basically being alluded to, Virtualisation is Serious Business.

HP NC-series NICs are pretty universally supported on ESX/i and cheap enough on Ebay, however.

 

Forgot to mention...

The NIC's are no problem. I've got a couple of Intel PRO1000's in my current ESXi box.

RAID is a no go at the moment. Do not have the budget.

For the sake of this thread, my current box is an HP DC7100. It's 'supported' by ESXi 3.5.
Even the IDE controller can be used to install ESXi on if you modify the install-script. For information on that, look here:

http://www.vm-help.com/esx/esx3i/ESXi_install_to_IDE_drive/ESXi_install_to_IDE_drive.php

Thanks for the info though

 

I'm up and running!!

ESXi 4.1 installed without a hitch. It can detect and use the onboard IDE controller, so there is no need to modify the install script if you plan to install on an IDE disk . The onboard SATA controller is also recognized. The disk that was attached, was formated as a datastore on install. I installed ESXi on an IDE disk because i will be using all the SATA ports for storage ).


The only 'problem' i have found so far is the onboard network controller not being recognized, but this was to be expected. I have two Intel PRO1000 and they work perfectly.

I think i will experiment with Xen in the future.

 

Good work Xtreme_Machine.

Paul