Question : Hyper V Server & Network Requirements

Hello,

I'm in the process of purchasing a new server that is currently a Fileserver, main DC, DNS DHCP and GP. I'm thinking of Hyper V for virtualization, so I may consolidate any new future servers and cut cost.

My Environment is Windows Server 2003 Std with over 250 users in AD. I have existing Groups and policies. I have DNS, DHCP, DC and Filserver on this old server I will replace. I have 5 other servers with mission critical apps/database sitting on server 2003 std, which are part of domain, but not DC. I also have a Exchange server 2007 and Citrix server both running Server 2008 STD. The server I will be replacing is a very important server to our network and I want to make sure I do this correctly. The new server that will be hosting Hyper V is a Dell PE R810 with a chassis for up to six 2.5 HD. I will have a PERC H700 Intergrated RAID Controller, RAID 1 for OS and RAID 5 for data. My processor will be 2x Intel Xeon E7540 2.0 GHz, 18M cache, 6.40 GT/s QPI, Turbo, HT, 6 CORE, 1066 MHz Max Mem. I will be running 32GB of Memory, 1066 MHz.

I'm looking to have 4 virtual server (sharepoint, Fileserver/DC/DNS/DHCP/AD, Citrix, Exchange backup) from this new server and I'm not sure if I'm purchasing the correct hardware for future expansion. I need this to work for 5/6 years max. Not sure if planning to far ahead is a good idea as servers grow old and the investment to upgrade is not a smart idea. I'd like to move our main server to Server 2008 Enterprise R2 which will have Hyper V. I'm looking for the best practices for this new server and how I could build this new server to meet future expansion without any issues latter. I appreciate if a expert can point me in the right direction as to how I can plan and launch this new project step by step.  

Thanks,

nimdatx

Answer : Hyper V Server & Network Requirements

So, just a view aspects:
1.) Server / Peocessor must support virtualisation (what is usually the case for newer processors)
2.) Each machine consumes memory and processor ressources. So to be sure, that your system will survive the next years, you should be able to expand especially memory.
You current system has a dual E7540 with 6 cores, this are 12 cores and 24 virtual processors. The next step are currently the extreme processors with 8 cores = 16 / 32. So there is not so much bandwidth what you can currently can have above your system. The next step would be a system with more than physical 2 processors.  

32 GB Memory is ok for the moment, if there is an option to add more memory, it would be an advantage.

If you share your system linear to 4 virtual machines, you have 6 virtual processors with 8 GB RAM per virtual machine. This is quite enough in my mind for current applications and you can apply memory and processors to the virtual machines as needed.

3.) Hard disc performance
You use 2,5'' disc, which are usually slower than 3,5'' disc. Nevertheless, if you use the 6 slots for a RAID 5/6, you can get acceptable performance. To raise the performance later, you can either replace the disc by faster ones (SSD disc may come up to 285 MB/s in compatison with fast 2,5 HDD with about 150 MB/s), or you can add a disc array, which limits currently to about 800 MB/s (10 GB Cable or 8 GB Fibre Channel.

Also keep in mind, that all applications will share the same disc array. The disc array should deliver high performance especially for database applications.

4.) Network
Usually you have 1 GB external interfaces, which result to a real throughput of about 75 MB/s (for all virtual machines to external). This is enough for clients, but may limit if used with other high performance servers. Such servers should be connected by their own with 10 GB interfaces, if they exchange a lot of data. How network is affected depends on how you place your applications onto different (virtual or physical) servers. Virtual machines are connected by virtual 10GB Adapters, so you can expects something around 750-800 MB/s. But this value is more theoretical, as it depends from the kind of traffic. The real throughput of databases may be much lower than the thereoretical limits. So this is more a question of intelligent placement of the applications to the right machine (virtual or not), rather then to hardware performance.

Summary:
What you currently plan should be enough for the current applications (in my mind). The question is, where the bottleneck may be and how to expand the system later if needed.
a.) Processor (no as board limited)
b.) Memory (dependend from the board
c.) Disc performance: yes (dependend from the construction)