And we can understand why. The basic gist of the change is a cap on the RAM you can apply to your virtual machines per license. Formally licenses were required on a per processor basis alone, now, if you reach the virtual RAM cap for the number of processor’s you have licensed, you will require extra licenses to cover any additional RAM. This increase caused the change to be dubbed the ‘Memory vTax’.

When VMWare first announced this pricing change the memory allowance per license were rather low, meaning (obviously depending on the configuration of the virtual machines) some VMWare customers were looking at their licensing costs being several times what the old pricing structure would have cost. Reacting to the complaints of their customers VMWare have now raised the cap, which should keep the license costs to a more reasonable level for most customers.

Here at GloNetworks we’ve always tended towards the Microsoft Virtualization software ‘Hyper-V’ over the VMWare options, and right now we’re more confident than ever in our choice. It could be argued that WMWares virtualisation software is more ‘feature-full’ however we feel that Hyper-V’s pricing has always been more appropriate for us and our customers’ requirements. And since Microsoft have appeared to confirm they have no plans to use a similar ‘Memory Tax’ in its next Hyper-V product (Windows Server ‘8’ Hyper-V) we’re sure this will continue to be the case.

I should warn you that this is a blog post aimed at technical people, who have some knowledge of Hyper-V clusters already, so if you’re looking at this from a “users” point of view you may get very lost, very fast. I’m not going to explain every little detail, because quite frankly we’d be here all day.

I feel I should start off by defining our “Private Cloud”. Cloud is term that thrown about a lot recently by marketing staff, and for that reason technical staff need to use it in front of boards and in front of the decision makers. To us techies it may be frustrating, however it’s the world we live in. If you’re uninitiated it’s a very broad term that covers:

• Infrastructure as a Service (IaaS) – Server and networking hardware, possibly server OS, such as Amazon’s AWS,
• Software as a Service (SaaS) – Software provided by a remote system, such as Google Apps (Mail, Docs, etc.), or Dropbox,
• Platform as a Service (PaaS) – Normally software infrastructure for developers to rapidly build software, such as force.com, Google’s AppEngine, or parts of Azure.

Whilst we also provide SaaS products, in this instance our small “Private Cloud” we see as an IaaS offering. It’s a small, 2 node, Hyper-V cluster that we use to run our own and customer’s systems.

As a rough outline our cluster consists of:

• 1x HP Procurve 2810-24G as our main switch,
• 1x Juniper SRX210 acts as our firewall and gateway device for some portions of our network,
• 1x IBM x3250 M3 acts as our physical Active Directory Domain Controller, and also hosts our Data Protection Manager (DPM) 2010 and System Center Virtual Machine Manager (SCVMM) virtual machine under Hyper-V,
• 2x IBM x3550 M3 act as our Hyper-V nodes,
• 1x IBM DS3512 acts as our shared storage,
• 1x QNap TS-459U+ acts as our short term backup storage,
• Several USB hard drives for off-site backup that are routinely swapped.

We’re aware that there are some issues with this design; single switch, single firewall and only 2 Hyper-V nodes. However the importance here is why we chose some of these things and why we don’t care as much right now (this was a significant investment for our small company);

1. Granted all hardware does die. In the event that a switch does we can get one on-site reasonably quickly if we needed to, however we’re yet to have a HP Procurve die on us since we’ve started business,
2. Single firewall is something that we worry about, but we’ve chosen Juniper as they are easily clustered,
3. Provided that you don’t over subscrbe 2 Hyper-V Nodes should be sufficient, however additional nodes can be introduced to the cluster easily in the future.

So whilst we are aware of the problems, I believe that we’ve engineered the system in such a manner that we’re able to introduce new hardware easily, upgrade the existing hardware, and provide some additional redundancy, including multiple switches with multi-chassis LACP links.

We’ve not built this system to compete with Amazon’s amazing AWS, however we have built it with 3 goals in mind:

1. Extensibility,
2. To use as a small reference design,
3. To virtualise our own systems more redundantly. The fact we’re able to host customer’s systems as well is a nice perk.

I won’t take you through the process of setting up your Hyper-V cluster, but I will cover a few bits and bobs that we feel a techy should be aware of before walking into a project like this, but might forget when looking at the big picture.

Clustered Shared Volume, or CSV, is the magic that makes the shared storage work. It’s a clever file system that allows multiple nodes to share the same storage. We’re yet to deploy a CSV using FC so we’re unsure if this is true for FC as well, however in the instance of both DAS and iSCSI what happens is the following;

1. The master node takes control of the storage,
2. All other nodes are notified of this, and effectively redirect all storage requests for the shared storage to the master node, over the network.

It should be clear from this that your choice of network card and switch are very important.

CSVs are not supported by Microsoft for any other use other than Hyper-V clusters. So don’t go getting any ideas.

Jumbo frames on your networking gear is a must. Generally speaking a Jumbo Frame is any ethernet frame that exceeds 1500 bytes, however they’re commonly also used as a naming convention for frames of 9000-9600 bytes (+/- 14 bytes for the header, depending on your switch(es)/NIC configuration language). If you don’t remember how IP and ethernet interact I suggest you go and refresh your memory very quickly. You should recognise the importance of having Jumbo Frames enabled very quickly; it should provide higher performance in situations where large payloads are being transmitted frequently.

At present we’re using Microsoft’s DPM 2010 to backup. The major gotcha that we didn’t see was that DPM 2010 on a Domain Controller is basically a no-no:

For a DPM server that is installed on a domain controller, only protection of data sources local to the DPM server is supported. You cannot install agents on other computers to configure protection.

SCVMM (System Center Virtual Machine Manager) 2008 R2 needs some polish. We’ve had to dive into the database once already. Don’t be afraid of it.

Other than that the project went exceedlingly smoothly. There are a few features that I wish Hyper-V had, in comparison to VMWare and Xen. And I really do wish that there were more, cheaper, graphics cards out there for RemoteFX.

However, that’s just something to plan for as a future project.

Windows cannot load extensible counter DLL TermService, the first DWORD in data section is the Windows error code.

The fix is a simple
Start > Run > lodctr tslabels.ini

Or run that in a command line to check it’s run as expected. This fix took too much digging around the internet to find so here it is a little clearer.

The bulletin is MS10-024, follow the link to be taken to the Microsoft site with full details. If you are affected by the problem and need a hand to resolve please don’t hesitate to contact us here at Glo Networks

We’ve not got our hands on it for testing yet but from reading this TechNet Blog article it looks like it should do exactly what we want / need.

We were part of the closed beta back in late 2007 and even then I remember wondering why a customer would want this. Where as SBS is perfect for small businesses most companies want the extra control of the individual applications. Interestingly though we’ve started moving customers away from even SBS an onto Microsoft Online (first one goes live this week) !

Glad we never recommended it for sale to any of our customers.

On setup I get a werid error ‘The Microsoft Online Services Directory Synchronization tool must be installed on a domain joined computer running Windows Server 2003 Serivce Pack 2 or greater.’. Hangon the server’s a Windows 2008 R2 Enterprise server and is a domain controler, so what’s the problem ? On digging around the MS site I find that it’s fine with Windows 2008 server but come accross this -

Installation on 64-bit environments not supported.

No way … surely not. Are we supposed to be using 64bit OSs now or not ? Exchange has been 64bit only for 2 versions or since early 2007 ! Even small hardware vendors are on the 64bit bandwagon.

Obviously now we know it’s not the end of the world but come on guys try to help us out just a little bit !

Project goals –

• Upgrade the servers to new hardware
• Save money
• Better way to backup
• Faster system

We purposed to the customer that we could make their current 6 physical server in to virtual servers and host them over two powerful physical servers on a much faster connection than they currently had, back all the servers up to separate location and save them money.

The customer accepted our proposal and we recently carried out the migration over a weekend, by Monday morning the servers were all up and running as virtual server on the two new servers. The new system will save them just more than £6000 a year.

Using disk2VHD (found here) we converted the physical servers, then transferred them to the new host and set them up on Hyper-V.

As well as having backup now done to a separate space away from the host servers it also adds an extra level of disaster recovery to their system. Should they have a hardware failure, being virtual servers we can have their system up and running very quickly (less than a day) on new hardware. All users had the exact same setup as before, the only difference they noticed was that their server was much quicker.

All of this also makes future migration, upgrades or add additional servers much easier thanks to virtual servers.

Symantec have recently released Backup Exec 2010 with some nice new features, with more systems going virtual can save a lot of time with backups and restores of virtual hard drives -

• Support for Exchange 2010
• Support for Windows Server 2008 R2 and Windows 7
• Enhanced support for Microsoft Hyper-v R2
• Continuous Data Protection for Exchange, File and SQL Servers

Hyper-V R2 support

Now from a single-pass backup, administrators will experience automated Log Truncation of a virtual machine applications. From that single backup, administrators can then easily recover either the virtual machine or granular application data such as Exchange mailboxes, messages, calendar items, and individual Active Directory user accounts or objects.

Continuous data protection for Exchange

Integrated Exchange 2010 support for the new Database Availability Group (DAG) in Exchange 2010 and enhanced granular recovery support provides fast recovery of individual email and mailboxes while eliminating the need to perform an additional mailbox-level backup.

Of course everything with Backup Exec is optional, you will need to buy the agent for each extra part you want to use.

The website we use is subnet-calculator.com, not very pretty by does exactly what you want in a clear interface.