Systems Engineering and RDBMS

Archive for the ‘VMWare’ Category

SQL Server and Virtualization

Posted by decipherinfosys on October 8, 2008

We have been writing about virtualization quite a bit. Most of our clients have migrated their web and application tiers to vmware/Hyper-V (or are contemplating to) because of the benefits that it offers but as far as the database tier is concerned in a production environment, there hasn’t been a mass adoption of it because of a couple of reasons – for the databases, IO is very important. If you have not done proper planning of building up a good IO path from your VM to your SAN device and if you are using vmotion, you can start seeing issues. vmotion is a very good technology and works great for print servers, file servers etc. but not for the databases. Our clients have been using it mostly in the development or test (QA) environments and for demo environments and only now have we started seeing some of them planning a move to the production environment as well. Before you do that though, you need to be aware of the best practices and performance implications of running SQL Server in a virtual environment.

While researching this topic more for our client, we saw this excellent whitepaper from the SQLCAT (Customer Advisory Team) which goes into the details of running SQL Server 2008 in a Hyper-V environment.  We are in the process of setting it up and will be doing more tests on it and will post results on our blog.

Posted in Hyper-V, SQL Server, VMWare | 1 Comment »

Data Center Virtualization

Posted by decipherinfosys on October 5, 2008

eWeek had an interesting article on the dark side of data center virtualization.  The author discusses the red flags that you should consider when thinking about virtualizing your data center environment.  You can read more here.

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Choosing between GSX and ESX Server

Posted by decipherinfosys on September 12, 2008

When it comes to choosing between GSX Server vs ESX Server for VMWare, most of the companies are Ok with using GSX server for their development and QA environments but prefer to use the ESX server for their data centers and production environments. Here is a simple bulleted list on what we think are the advantages of using ESX over GSX.

Advantages of ESX

  • ESX is by far the most scalable and reliable product to work with in Datacenters in that it provides VMotion which allows machines to dynamically switch from one hardware box to another either upon a failure or an overload of that hardware box without the loss of service. Here is a link that explains this in more detail.
  • Secondly, ESX is now supported under the Microsoft’s Server Virtualization Validation Program so that if there is an issue with the Microsoft OS or application running on ESX, they will support it if running on ESX 3.5 u2. So, for shops that are Microsoft technology based shops and do not want to go to Hyper-V yet, they can move to VMWare without hesitation since it is supported now.
  • Because it is loaded upon a Linux OS, ESX server has the advantage of not needing security patch maintenance, and more importantly, it greatly mitigates the possibility of a problem with a security patch causing all the VM’s on the host server to be affected.
  • Because of ESX running on Linux, there are important performance advantages that are available for RAM and CPU that are not available with GSX due to the limitations of the Windows server which VM is loaded upon.
  • If you want to run the base version without the data center capabilities provided in VirtualCenter, it is still free to download and allows you to scale as your needs require. Some of our clients are presently utilizing ESX for their off-shore outsourcing development needs.

And here is the link to another article that validates the consensus that if one wants to use VMware in a production/data center environment then the only real choice is ESX.

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VMWare now has MSFT validation in SVVP

Posted by decipherinfosys on August 22, 2008

Read on one of the blog posts here that VMWare has now joined MSFT’s Server Virtualization Validation Program (SVVP). VMWare is added to the SVVP web site as well. So, what does it mean to us? It means that unlike before, MSFT will now provide support for a number of it’s server operating systems when they are running in a VMWare environment. This is the list of the supported operating Systems: Windows Server 2008, Windows Server 2003 + SP2 and above, Windows 2000 Server + SP4.

Posted in VMWare, Windows | Leave a Comment »

VMWare Hypervisor is free now

Posted by decipherinfosys on August 4, 2008

VMWare has announced that it’s ESXi hypervisor will be made a freeware. You can read more on it over here.  This move is apparently to counteract the open source Xen hypervisor and the Microsoft’s $28 hyper-V.

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Converting Physical Servers to Virtual Machines

Posted by decipherinfosys on July 24, 2008

In almost any virtualization project, you will run into the need of converting physical machines to virtual machines. Both VMWare and Microsoft provide solutions for that. Here is the link that gives the details of the vmware converter. And here is the link for the Microsoft Virtual Server Migration Toolkit and another one that details VMM (Virtual Machine Manager) over here.

We have used the vmware one quite a few times and it is pretty easy to use and very robust as well. It does not require any downtime either. Haven’t had any experience with the MSFT toolkit so will post on it once we play with it in our labs.

Posted in Virtual Server, VMWare | Leave a Comment »

Virtualization Wars

Posted by decipherinfosys on July 11, 2008

We have covered virtualization before at our blog but mostly VMWare and a couple of posts on Virtual Server as well. With Windows Server 2008’s Hyper-V, it looks like it will challenge the market even more for ESX Server 3.5. With hardware changes coming in way faster than the software changes, the servers age out faster due to hardware issues rather than the OS. With virtualization, a physical server can easily be migrated into a virtual environment with the same applications and then moved on to a new physical hardware. We have clients who are using virtualization now even in their production environments let alone the development and QA environments.

If you are not already using virtualization in your environments, now would be the time to start getting serious about it. With Hyper-V, the technology moves the virtualization layer directly against the hardware. Hyper-V allows virtualization of both 32 bit as well as 64 bit architectures. MSFT has extended their virtualization platform offering by providing Microsoft App. virtualization (this was known as SoftGrid before) and desktop virtualization. not only that, one can use the System Center Virtual Machine Manager to do centralized management of a virtual set up.

Not only are these choices cost effective by providing us with consolidation and DR/HA (Disaster Recovery and High Availability) choices, it also eases up maintenance work for System Engineers as well as DBAs. An added benefit of consolidation is reduced electricity costs 🙂

Both ESX Server 3.5 and Hyper-V are based on hypervisor based architectures which are better than the previous hosted virtualization technologies. In the case of the hosted virtualization products, one had to run the virtualization software on top of the OS of the machine and that adds a lot of overhead and not only that, it has a longer code execution path for the VMs. Hypervisor based architectures run the hypervisor directly on the hardware which means that there is no OS between the hypervisor and the system hardware. Even though both ESX Server 3.5 and Hyper-V as both based on hypervisor base architectures, there are a good bit of differences between them. We are currently doing some benchmarks with ESX Server 3.5 as well as Hyper-V and will post the results of the tests at our blog as and when they become available and we consolidate them. Till then, you can read more on these over here:

ESX Server 3.5

Hyper-V and the FAQs

Posted in Hyper-V, Virtual Server, VMWare, Windows | 1 Comment »

Virtualization in the database world

Posted by decipherinfosys on October 26, 2007

Virtualization is rapidly changing how we consolidate our servers for testing and deployment, for training and for disaster recovery. We have VMWare machines running in our office with clustered SQL Server and clustered Oracle environments. It is a great way to test out new software and play around with the new functionality as well as test out your disaster recovery scenarios without investing millions on hardware. It is also a good way to consolidate your servers and use them for development and QA purposes.

Both VMWare’s VMWare Server and MSFT’s Virtual Server 2005 R2 support 64-bit architecture on the host which means more memory utilization on the host seerver (up-to 1 Tera-byte) which translates into the capability of running many more active VMs. When you are getting ready to consolidate your servers into the VMs, you should remember to allocate 32MB per VM to account for the VM overhead. So, if you have an Oracle database for which you have allocated say 2GB of memory (overall), when you move to the VM, you would need (2 * 1024) + 32 MB for the VM. And you need to ensure that there is enough RAM left for the host as well. Another thing to consider is the usage of a SAN for the host server. You should create the VM’s virtual hard drive on a drive that is different than the host’s operating system – this is to reduce any possibility of a drive and spindle contention. Best thing is to use a SAN to help improve the I/O for the VMs. One more things to remember is that the virtual hard drives can be configured with their default settings to dynamically expand as needed. However, this is not good for performance. We would recommend to pre-allocate a fixed amount in order to avoid the performance hit of the expansion.

Here is the link to the whitepapers from VMWare on this topic:

Posted in Virtual Server, VMWare | 1 Comment »

Configuring RedHat Linux AS 3.0 virtual machine using VMWare

Posted by decipherinfosys on June 7, 2007

Here are the steps to configure a RedHat AS 3.0 virtual machine using VMWare:

1)    Start the Host Configuration in the VMWARE console.

2)    Right click on the Virtual Machine you wish to configure and choose “Virtual Machine Settings”.

3)    In the screen that pops up, choose the NIC (usually NIC1) you wish to configure.

4)    On the right hand side of the screen change the “Adapter Type” to vmxnet.

5)    Once this is done you will need to start the Virtual Machine.

6)    Once the Virtual Machine is booted, log in as root.

7)    Once logged in you will need to open a terminal. (Command prompt).

8)    Type the following using the same case:

9)    Execute  (when prompted, choose “no” when asked if you wish to change your guest x resolution).

10)    Execute the following command:
/etc/init.d/network start

11)    Click on the start button in the bottom left (a red hat).  Choose “System Settings” then choose Network.

12)    A screen will pop up.  Delete any failed/non-working devices.

13)    Click New, then Ethernet Connection, then Forward.

14)    Choose “vmxnet” and click Forward, then Forward again, then Apply.

15)    Save the Changes when prompted.

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VMWare Symposia 2007

Posted by decipherinfosys on April 13, 2007

VMWare holds a number of national and regional conferences every year, and best of all the majority of these conferences are free of charge. The VMWare Symposia is one such conference, and is an outstanding way for virtualization novices to become more familiar with virtualization technologies, and for experienced VMWare fans to interact with their peers. Even the most senior VMWare administrators can learn something new – it has been the author’s experience that not a single conference or meeting has gone by without gaining some new knowledge.

Symposia 2007 is being held in a number of major cities in the United State and Canada, incuding Atlanta, Dallas, Chicago, and Toronto. It is a day-long deep dive into some the latest VMWare products and technologies. Highlights include presentations by virtualization experts, customers, and industry analysts, live demos of virtualization solutions, case studies, and free software handouts at the end of the day.

To learn more about and register for Symposia 2007 visit VMWare’s Symposia website at:

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