how can i consolidate our servers through virtualization? i need to know the hardware requirement?

Chandan,

How many servers do you have in total? As I mentioned earlier, you're not going to want to consolidate all your servers into a single virtual environment, because if there are any problems with that physical environment, you will have zero access to 100% of your servers. So, you're going to want to deploy 2 servers and enable some sort of load-balancing or redundancy for your guest operating systems -- depending on how they have been built.

Based on my experience, I would consider a pair of host systems systems with the following minimum specs:

-- 4-way, quad-core system, with hardware assisted virtualization support
-- 16-32GB RAM
-- 2ea or 3ea -- Dual Port GbE NICs
-- 2x 73-80GB SAS or SATA for OS (Mirrored)
-- Additional Storage (Local or SAN)
-- VMSphere 4 OR Windows 2008 R2 w/Hyper-V Enterprise Edition or DataCenter Edition

Here are some of the questions that needs to be answered before full specs can be recommended:

- How many servers do you have now?
- What are the full specs of your existing servers (especially storage)?
- Do you currently have a SAN?
- What are the security requirements between your existing networks?
- How do you currently backup these systems?

Unless you tell me you have under 10 servers total, and less than 1TB of total space, you're not going to just want to run out and purchase hardware. You would be well advised to speak to an IT Services provider that implements virtualization, and engage their assistance.

For reference, you can see what I deployed on my home network using Hyper-V on Windows 2008 R2. I didn't use a SAN at home, but all of my corporate virtualization deployments (3+ now) have involved a SAN in the 8TB to 20TB range, depending on needs.

Here is the summary of my experience on my home network:
http://home.asbzone.com/ASB/archive/2010/02/22/home-network-overhaul-2010-con...

Hope this helps...

-ASB: http://xeesm.com/AndrewBaker

The type of hardware you want to choose for you virtualization infrastructure depends on the number of servers you wish to consolidate. A typical dual socket server running quad core cpus can handle an average of 8 to 10 guests, depending on the type of apps they serve. For example, fewer database servers can be placed on a host than, say, web servers. I have achieved densities in excess of 20 servers per host for low-demand applications. You will find that memory is your limiting factor, and this also assumes you have a decent storage solution to pair with your hosts.

If you have a large number of servers relative to the density quoted above, you may want to move to blade technology to gain an additional lift in power and space consolidation. If you are trying to minimize any additional hardware purchases, you should try to develop a plan that turns a portion of your existing hardware into virutalization hosts.

"We want to consolidate our servers so that we can manage it easily."

Reducing the physical count won't necessarily make the administrative side any easier, especially if you simply move 10 physical servers onto 10 virtual machines - you still have 10 systems to look after.

What server software are you running presently (MySQL, IIS, etc..)?

Hi Experts,

I am agree with you. through virtualisation we can reduce below things.

1)Extra hardware maintenance.
2) Electricity.
3) Space Issue
4) Server managemnet issues.

We are running SQL, Some customized Software, VB, Mail Server(IMAP), CRM, AD, TS.
and i want all the servers into single good configuration Server So please suggest me the Machine(CPU,RAM), with having RPS rack mountable, virtualization features.
Or
Suggest me what solution should i opt for above?

Regards,
Chandan

Regarding Robin's comment, it is true that you will still have the same number of servers to administer after virtualizing them. The burden of administration, however, is reduced by the fact that, assuming a single virtualization product is employed, the server hardware is effectively standardized across the board. Your video, network, disk, keyboard and mouse are the same on all servers. For this reason alone, we recommend virtualizing, even if you only run one guest on the host. This feature frees your applications from being tied to the hardware lifecycle. For example, if you had a business critical application that only ran on Windows NT, you could theoretically continue to run that indefinitely while changing out the underlying hardware as it ages.

One of the biggest administrative burdens in managing a server is keeping the operating systems patched. Some products, most notably VMware, provides the ability to patch guests from a centrally managed repository. VMware also provides a number of data center-centric applications that further ease the administrative burden. You can see, at a glance, which servers are consuming various resources, allowing you to more quickly pinpoint bottlenecks. Fixing those bottlenecks can be a very simple matter of adding additional memory or disk space, which is all done from an application -- you don't need to crack a cover or worry about static discharge!

Andrew made a good point about planning and saving on licensing. If you use multi-tier architectures for your systems, and group servers running similar platforms, like Oracle and WebSphere, on their on host clusters, you will be able to better manage licensing expenses.

In short, virtualization allows administrators to focus more on their applications and less on the infrastructure supporting them. Hardware becomes more of a commodity and administration does get easier. Depending on your organization's internal structure, you may even be able to maintain seperation of roles and responsibilities, particularly with VMware's introduction of distributed switch technology and Nexus.

I concur with Andrew's assessment. You never want to place your production systems on a single host. Always think in terms of a cluster of at least two hosts and set up high availability between them. That requires a shared storage mechanism, usually a SAN. At work, we have a fiber SAN in excess of 40TB supporting several hundred virtual servers, which, in turn, run on multiple 2- and 3-host clusters, depending on licensing and security requirements. For my consulting business, I am building an 8TB SAN using iSCSI rather than fiber to save costs. I can scale it up to 16TB at a cost of less than $180 per TB.

To determine the size of your hosts, you need to look at the cpu, memory, disk and network utilization of each server you wish to virtualize. Do not necessarily go by what is installed on your physical servers, look at what is actually used. If some servers show signs of overutilization, make note of which resources they are low on.

Some servers may not be candidates for virtualization because they contain special hardware or interface cards. For example, VMware does not recommend virtualizing servers that have USB peripherals or perform real-time operations.

I do have a bias toward VMware, as I am a certified consultant. I usually recommend VMware as the platform of choice, unless you already have an infrastructure based on the Microsoft Server 2008 titles that Andrew mentioned. Microsoft used to have an odd licensing scheme whereby you had to have at least 5 physical servers before your virtual guests become licensed. I believe Microsoft dropped that.

VMware is a true bare-metal hypervisor written from the ground up. Microsoft has a solution that employs a stripped down version of their Server. Xen is also similarly layered on top of Linux. Such layered products have additional vulnerabilities due to the underlying operating system components.

In any case, as Andrew mentioned, definitely engage a certified virtualization professional to go over your existing infrastructure and put together a migration strategy that fits your goals and budget. Depending on what you have already, you may be able to leverage existing assets to build your farm.

Chandan, let me encourage you not to put the cart before the horse. Don't look at virtualization with the narrow view of merely consolidating servers. Take a few minutes to watch this short (45 min), free webinar about developing a strategy for virtualization. It will help point you in the right direction and save you time and money by avoiding common mistakes.

http://www.brighttalk.com/webcast/21376

Good Luck.