Archive for January, 2013

Funny how this article appeared on LinkedIN on my last day here at the City of Durham. While the ride here has been a great one and I have worked with some awesome technology it was clearly my time to move on with life. I am grateful to have worked with the individuals who welcomed me here on day 1 and are celebrating my departure at lunch today. Their mentality rings true to the article I posted because they are sad to see me go; however, they are also happy to see me advance in life and take a job that fulfills a dream.

Clone Template
Clone creates an exact copy of a running Virtual Machine at the time of cloning process Template acts as a baseline image for a Virtual Machine with the predefined configurations as per your organization’s standards.
Cloning a Virtual Machine creates an exact duplicate copy of the Virtual Machine with the same configuration and installed software without performing any additional settings. Create a template to create a master image of aVirtual Machine from which you can deploy multiple virtual machines
You can create a clone of an existing installed and configured running Virtual Machine by right clicking on it and selecting Clone. You can create a template by converting a Virtual Machine to a template, cloning a Virtual Machine to a template, or cloning another template.
VM clones are best suited in test and development environments where you want to create, test and work; with exact copies of production servers without disturbing production servers by creating a clone of the production virtual machine. Templates are best suited for production environments where you want the mass deployment of Virtual Machines along with the installed OS, basic software, and configured settings such as the security policy of your organization, as a base VM. Once a template is deployed, you can install software depending on the role of the server for example IIS or Database.
VM Clones are not suited for mass deployment of Virtual Machines. Templates are best suited for Mass Deployment of Virtual Machines.
You cannot convert back the cloned Virtual Machine. You can convert the template back to Virtual Machine to update the base template with the latest released patches and updates and to install or upgrade any software and again convert back to template to be used for future deployment of Virtual Machines with the latest patches.
A Cloned Virtual Machine can be powered on. Templates cannot be powered on.
You cannot clone a Virtual Machine if you have connected directly to an ESX/ESXi host using a vSphere Client. You cannot create a template of a Virtual Machine if you have connected directly to an ESX/ESXi host using vSphere Client.
You can customize the guest operating system of the clone to change the Virtual Machine name, network settings, and other properties. This prevents conflicts that can occur if a Virtual Machine and a clone with identical guest operating system settings are deployed simultaneously. You can also customize the guest operating system while deploying from a template.
A Clone of a Virtual Machine can be created when the Virtual Machine is powered on Convert virtual Machine to template cannot be performed, when Virtual machine is powered on.  Only Clone to Template can be performed when the Virtual Machine is powered on.

A quick tidbit of information useful in troubleshooting and interviewing and reviewing the logs (if you can) before you start hacking away at the issue. It makes no sense to start diagnosing an issue if you have logs that can, hopefully, tell you what was going on before and after an event that caused an outage. For instance, if your wireless just decides to go down you may want to look at the lgos in the AP (autonomous mode) or the controller (Controller mode) and see what was happening. Given there is enough verbosity in the logs it should tell you what happened and you can take corrective measures. This applies to interviews because people always ask “What are your steps to figuring out what happened?” I always start with: I check the logs.

In the days of Windows Server 2003 there were no native tools to expand a partition into contiguous free space; however, you could “extend” it to another drive but this wasn’t the same. Thus, back in ‘the day’ you had to provision enough storage to grow with the server and updates. If you were intelligent enough you would have created a separate partition for data but in my experiences this was never the case and stuffed to the max C: partitions were common. However, with the proper tools you could have extended the NTFS partition if you were comfortable enough doing so (and had a good backup). Today the majority of Enterprises are running Windows Server 2008 and this includes a native feature to extend a file system into free space you provided on the drive, similar to extending the file system on a Linux system.

Thus, I highly recommend only giving your system enough space as needed if storage is at a premium for you and extend as needed, especially if you have third parties demanding ridiculous storage requirements you’ll never use.

Ever wonder when you’re working late and you want to nuke that frozen burrito in the freezer and come back to your desk to find that 12GB file is no longer being downloaded and you notice that you reconnected to your wireless network? Well, depending on what band you’re running in, namely 2.4GHz, you probably killed your wireless network connection because microwave ovens send frequencies within this band and a small leakage of these waves left the microwave and interrupted your connection. The solution? Check what channel you’re running in. If you’re using 802.11g then you’ll ONLY have channels: 1, 6, and 11 to choose from because all others in between overlap too much. Generally, if you move to channel 1 you’ll be just fine (from my experiences) but I would recommend experimenting with the channels to see what suits you best.

Here is a quick and easy script to run on the command line that will give you the location of the delta files if you can’t see them in snapshot manager:

find -follow -name '*delta*.vmdk' -exec ls -alh {} \;

I have learned a lot in my years in IT and if there is one valuable lesson to be learned is to remove all DEFINITE conclusions from your thought process until you have deductively ruled out ALL possibilities. We all have been in the situation where we say “No, it can’t be this because…XYZ”; however, we all have been found wrong and we must wear egg on our face (and this is a problem for me since I am vegan).

I have found it is much better to take a neutral stance and develop a plan that utilizes deductive logic to isolate the issue and to include everyone involved along the way, from the cabling guy to the server guy because you’ll never know where the problem lies if you just point the finger and pass the buck. Think about it, if you’re the one collaborating the effort to solve the problem, even if the problem is on your end, you’ll still be the hero because you developed the plan and executed it.