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motiveitFlag for Australia

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Terminal Server High Availability on VM Server

Hi Experts. I have been tasked to build a Terminal Server (RDS) for 10 clients to access an LOB application with high availability (no more than 1 hour down-time) in a Small Business with High Availability needs, without a large budget for multiple servers.

I'm looking for suggestions based possibly on 2 Physical Servers with VM ESXi 5.1 and Server 2008 R2 DC and RDS guest servers on each host with the second server being the HA server.

We can run a manual switch-over method so we don't need to use Failover Clustering as this would create the need to have 2008 R2 Enterprise on all servers. Is it possible to achieve this with 2008 Standard, and if so, can it be done with only 2 OS licenses rather than 4?

Also, can this be done with the VM Datastore on an iSCSI Storage Server so the VMs are quite small and can be mounted quickly?

Any help will be much appreciated and 500 points awarded for the solution.

Look forward to hearing your suggestions.
Avatar of Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
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Yes, you can use an iSCSI Storage Server to store VMs. It's standard to use an iSCSI SAN or shared storage for this purpose.

You could also use VMware HA, which is a function of VMware, this is available in VMware vSphere Essentials Plus, which inlcudes 3 x Licenses for VMware ESXi, 2 CPUs each, and vCenter Server.

If a HOST should fail, the VM will be restarted on the other hosts automatically, this takes approx 60 seconds.

or you could use vMotion, to Live Migrate VMs.

see here

VMware vMotion - Migrate Virtual Machines with Zero Downtime

VMware vMotion Product Brief

VMware High Availability - Decrease Downtime and Reduce Risk

VMware High Availability (HA) Product Briefs

See my EE Article

HOW TO: Add an iSCSI Software Adaptor and Create an iSCSI Multipath Network in VMware vSphere Hypervisor ESXi 5.0

HOW TO: Enable Jumbo Frames on a VMware vSphere Hypervisor (ESXi 5.0) host server using the VMware vSphere Client
Ok this is really going to cause the VMware guys to crap on me but given your situation I think you should scrap the idea of using VMware.  You're on a tight budget and need enterprise features, right?  Instead of the free version of VMware you should really consider using Hyper-V Server 2012.

What most people don't realize is that the actual product named Hyper-V Server 2012, just like 2008 R2, is not only free but it's the full version of Windows Server with all of the enterprise features at no cost.  Failover clustering has always been included for free with this product.

Yes you can use iSCSI storage with Hyper-V... you can use any storage to be honest since with the release of 2012.  The performance is top notch, there are no restrictions on memory or processor allocations and it is a rock solid system.  I've been deploying production hyper-v clusters for several years now in networks all over the country and not one of them has failed yet.  With your virtual environment in place you can spin up whatever number of virtual servers you need for your services and users...  

If you have any questions on this please definitely feel free to post back... it is obviously your choice but I really recommend you consider it...
You could use the FREE version of ESXi, configure 2 servers with ESXi for FREE.

and then use VMware vCenter Converter Standalone 5.1 to "replicate/sync" the virtual machine from one server to the other!

see my EE Articles in what I call....failover time will be faster than 60 minutes!

"Poor Man's Replication of a Physical or Virtual machine to a VMware vSphere Hypervisor Host (ESXi) for FREE"

HOW TO:  Synchronize changes when completing a P2V or V2V with VMware vCenter Converter Standalone 5.1

HOW TO:  P2V, V2V for FREE - VMware vCenter Converter Standalone 5.1
See what I mean?

VMware guys always throw a fit when someone talks about Hyper-V... to be honest though that's the only way VMware will stay in business long term...  they already had to change their pricing after 2012 released although VMware guys will swear on their mothers that it had nothing to do with Microsoft and it was simply due to "user feedback"...

Your call either way man... just don't paint yourself into a corner of less features and more manual work just because it has the name VMware... you'll get bullied for sure by the VMware guys but you'll be able to sleep much better at night...
@jpgobert Not throwing a fit here my friend.

OP mentioned ESXi 5.1, Asker maybe currently trained or familiar with VMware Products, if he wants to discuss Hyper-V, I will be happy to discuss Microsoft Hyper-V or Citrix XenServer. The question is also posted in the VMware Zone.

Read my latest article!
...As a Virtualisation Consultant, we implement many different virtualisation solutions using VMware vSphere, Citrix XenServer and Microsoft Hyper-V, as per client requirements. Most fall into the VMware vSphere camp, but that does not prohibit us, from using equally good Corporate Enterprise Hypervisors from Microsoft or Citrix, as both are now "considered equal"......

HOW TO:  Add a Dell EqualLogic PS Series Array (SAN) to System Center Virtual Machine Manager 2012 SP1 as a SMP Provider

No worries man I'm just poking at you :)

I know he posted in the VMware section but to be honest there are a lot of folks out there who still don't know that hyper-v is truly a viable enterprise solution.  VMware has been around since my grandmother rode a brontosaurus to work every day so everyone knows what they're about... anytime I see someone wanting to go virtual, needing some enterprise features, and thinking they can only go ESXi I try to at least get them to look at Hyper-V.

At this point I can't even think of a good reason for someone who doesn't have an investment in VMware yet and who runs a Microsoft shop to even think of spending money on VMware licensing.  Obviously if you already have an investment in licensing then it makes sense usually to stick with it... otherwise there's just no good reason anymore... that's got to really scare the hell out of VMware...
Avatar of motiveit


Good feedback guys. I'm not closed to Hyper-V, it's just I've had a lot more experience with ESXi. I'm interested in the Hyper-V angle though, but my earlier experiences with hyper-V were not easy. Just as a question for jpgobert, how does Hyper-V handle the OS licenses on the DC server and RDS Server guests as well as the failover copies?
And thanks hanccocka for your feedback too, as you rightly say I did post this with a mind towards ESXi, but I'm always open to options and ideas.
I'll certainly look into both options, and any additional advice from both sides of the fence.
There's no licensing involved with Hyper-V.  Any VM's you deploy under Hyper-V are licensed just like they would be if they were on physical hardware.  Now, with the release of Windows Server 2012, Microsoft has changed how licensing works in regards to server specifically regarding virtualization.

A single license for 2012 Standard covers installation on a physical server with up to two physical processors plus two 2012 standard VM's running on that physical box.  A single license for 2012 Datacenter covers the physical server with up to two physical processors and an unlimited number of 2012 Datacenter or Standard VM's running on the same box.  The licenses are "stackable" as well.  Whatever server OS licenses you'd have to have if you ran this under VMware is basically the same server OS licenses you'll have to have to run under Hyper-V.

Make sense?  Does that answer your question?  I'm definitely happy to help you pull together more details and I'll answer any questions you have on hyper-v and such.

Licensing for the VM OS, for both VMware ESXi and Windows Server 2012 are the same.

Hyper-V 2012 is free, and is just used to Host VMs, which still require a license, and you also need to use another workstation to Manage Hyper-V 2012, just like ESXi, but you can do Hyper-V Clustering and VM Replication for FREE, unlike ESXi.
Just to make sure this is clear...

If you download and install Hyper-V Server 2012 you will end up with what is basically an install of Windows Server 2012 Datacenter Core with Hyper-V.  There's no GUI to core installs... but that's really not an issue since the server is fully manageable from your PC when you have the Remote Server Administration Tools installed.

There is no functional difference between Hyper-V Server 2012 and a full install of Windows Server 2012 with the Hyper-V role installed except for the full GUI and the ability to install additional non-hyper-V related roles and features.  In all honesty though you really wouldn't want to add non-hyper-v related features and roles as that would just add host overhead to your virtual host.  The point is that you're not losing anything by going either way...

FYI... The Hyper-V Management Console, which is a part of the RSAT kit, is different for 2012 than it is for 2008 R2.  Basically 2012 supports more features and options than 2008 R2.  If you're going to manage it, or any other 2012 server for that matter, you need to either have a Windows 8 installation you plan to use or have a VM of Server 2012 on your workstation just for managing your servers.
Thanks again for your feedback, it's really helpful.

In the physical environment for this deployment, the requirements for their LOB solution is for Server 2008 R2 and Windows 7 desktops or any thin client terminal.
They need to have a Domain Server and a Terminal Server running at all times to allow
their applications to run, with at least 1 Windows 7 Desktop to run other apps.

We will need to have the virtual copies available to boot up in the event of physical server failure, although these do not need to be run for load balancing during normal operation.

If we were to purchase Server 2012 Standard licenses for the Host, and then downgrade the guest servers to Server 2008 R2, do we need 4 licenses of Server 2012 Standard for this or only 2 if we are going to replicate the virtual servers and mount when needed.

Also, I wasn;t planning on adding a Windows 8 PC into the network at this stage
in the event of failure, you would only need 2. (as long as both are not on at the same time, which they wont because it's fail over only).
@motiveit... sorry for the delayed response...

If I'm reading you correctly it seems like you're saying that the virtual infrastructure will only become active during a physical downtime event...?  If so... you can save BIG time on licensing if you're buying open licenses for your machines.  If hyper-v server 2012 is used for the host server there's no license required there... if instead of building separate VM's as your backup systems you can pick up a backup software package that backs up your machines as virtual machines.  If you do, and your OS licenses are open licenses, you can boot that virtual backup of your physical systems on your hyper-v server during physical downtimes without violating licensing terms.

...may or may not be an idea for you...?

In any case, the rule of thumb with licensing is to make sure you have a valid license for any installed instance of Windows that will be in use.  If you're planning to back up a physical machine with a VM and that physical machine has an OEM license then you're restricted as to when and how that license can move to a virtual instance during downtimes.  I'd need to look up the latest revision of MS's licensing terms...

I can tell you for sure that if you were to buy two 2012 standard licenses and applied them to a server running hyper-v server 2012 you'd be licensed for four VM's running 2012 or an earlier version via downgrade rights.
It seems from research I have done today, that regardless of the host OS (ESXi or Hyper-V), I would need only 1 Server 2012 Standard license if I were running the second server as a cold DR Server, only booting up when the Production Server stops working.

The only thing I have that I'm unclear about, is how to make the VMs in the DR Server keep in sync with the Prod. Server without having the DR Server running. I understand we can boot the DR servers to do Updates and Patching, but not daily syncing under 1 license.

Therefore, it seems that it would be better to run both servers 24x7 with 2 licenses of Win 2012 Std so we can run 2008R2 Enterprise for the Prod. DC and RDS Servers with Failover Clustering to keep the DR DC and RDS Servers in Sync. This would then give immediate failover instead of manual Switch-over, but paying for 2x Win 2012 Std licenses. Am I right?

Question for @jpgobert - Are you saying that if I ran Win 2012 Std Hyper-V as the host OS on both servers, with failover clustering now available in 2012, this would keep ALL the servers (2 Host OS and 4 Guest OS) in sync, or would I still need 2008 Enterprise on the Guest OS's to run the failover for the DR Guests? Does that make sense?
Sorry @jpgobert, I forgot to mention that I read that you could use OEM 2012 Std on both Physical Servers instead of OLP (about 1/2 the price) which would still give downgrade rights to 2 VMs each license. The only problem I see though is that you'd need media for 2008 Enterprise with install keys to install the VMs if we actually need Failover Clustering at Guest level.

This I think may be a good option if either we don't need FOC at Guest level if it can be done by the 2012 Hyper-V, or if we go for the Cold DR Server approach but with an OEM license for each server. What's your thoughts?

I know the ESXi route would mean 2 copies with 2008 R2 Enterprise so we could get FOC on the guest OS's.
If it were me doing this setup then I wouldn't install the production server OS onto the bare metal.  I'd run a hyper-visor on the metal and run the server as a virtual machine.  That would allow you to boot it on another virtual host with little to no problem.  It also makes it easy to maintain replication since 2012 supports replicating between servers with separate storage.

The only thing to consider, if you're worried about it, is that MS does have a limit on how often you can move a license.  I think its dumb but it is what it is.

If you don't want to do what I mentioned above you can look at using backup software that actually creates a VM backup of the machine when you run system state backups.  A lot of 3rd party backup software products now support this because of virtualization being so prevalent.  For that matter you can even keep it free by using a P2V tool to snapshot copies of your physical server on a regular basis into a VM.  

It really all depends on how much you want to spend on what and how you want to set things up...
The problem you're going to run into with OEM licenses is that you can't freely move them per MS licensing.  How you want to handle that is your deal obviously but it is something you should at least make sure you can answer questions on.  I don't know who the stakeholders are for your project which is really why I'm bringing this up...
Sorry @jpgobert, I may have misled you. I was planning to install a hypervisor as the host on Production Server bare metal, then install 1 instance of 2012 Std on the VM Guest Domain Controller and 1 instance of 2008 R2 Enterprise or Std on the VM Guest Terminal Server.

Then replicate that on the DR Server. I'm assuming I need 2008 Enterprise on the Terminal Servers for Failover Clustering, or is this done at host hypervisor level if you install 2012 Standard with Hyper-V as the Host?

I'm happy to live with the overheads of the GUI on the Hyper-V so we can install a management agent on it for monitoring purposes.

So, in this case, is it necessary to move the OS licenses if we're replicating through FOC?

If we use Failover Clustering, is it necessary to have the data on iSCSI Storage instead of on the VMs? Wouldn't this make a single point of failure for the data?

To keep this simple, you need

Production Site

1 x Production Windows 2012 Standard with Hyper-V role
this server hosts
VM Guest Domain Controller
VM Guest Terminal Server

Hyper-V replica replicates the above VMs to:-

DR Site
1 x DR Windows 2012 Standard with Hyper-V role
Replica VM Guest Domain Controller
replica VM Guest Terminal Server

How and where do you want your Failover Clustering?

No requirement for iSCSI Storage, as you replicate from Production to DR.

What do you want to do with iSCSI Storage?

Does the above give you enough resilience and availability?
Thanks @hanccocka, simple is best for me. You have it right for the layout I think. I'm guessing that if we have ESXi on both hosts, Failover clustering would have to be done at the Guest OS level, therefore need 2008 Enterprise to get this.

What I was asking was if I use Hyper-V as the host, does this do failover clustering at the Host level,  replicating all the VMs on it? If so we only need 2008 Std on the Terminal Server I think.

Is that clearer from me or more confusing?
Avatar of Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
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