Archive

Posts Tagged ‘virtual machine’

Uniqueness of MOIDs

August 16th, 2011 8 comments

A question was recently posted at the open source VI Java API forum regarding the uniqueness of MOIDs. The developer who raised the question wanted to build a caching on the client side so as to avoid getting back to the server for the name of a virtual machine with its MOID. If MOID doesn’t resonate with you, you may want to read this post before reading on.

Why Virtual Machine Not Found?

June 30th, 2011 No comments

I saw a new bug (Intermittent ManagedObjectNotFound on VirtualMachine.getConf) filed in the open source VI Java API project today:

It looks like sometimes VirtualMachine.getConfig() returns null, but other times it throws:
Caused by: java.lang.RuntimeException: com.vmware.vim25.ManagedObjectNotFound
at com.vmware.vim25.mo.ManagedObject.retrieveObjectProperties(ManagedObject.java:158)
at com.vmware.vim25.mo.ManagedObject.getCurrentProperty(ManagedObject.java:179)
at com.vmware.vim25.mo.VirtualMachine.getConfig(VirtualMachine.java:55)

As the vSphere API reference points out,

Moving Virtual Machine Back From Distributed Virtual Switch

June 29th, 2011 2 comments

After blogging about moving virtual machines from a standard virtual switch to a distributed virtual switch, I saw a new question in VI Java API forum on how to roll it back. Technically, I don’t see any reason why one should switch back because using distributed virtual switch gives you a lot of benefits. But the decision is not mine but yours. Whatever you want to do, we help do it easily.

The method involved is

Moving Virtual Machine to Distributed Virtual Switch

June 14th, 2011 1 comment

The distributed virtual switch introduced in vSphere 4 has many benefits over the traditional switch. For one thing, you no longer have possible glitches with live migrating virtual machines from one host to another using traditional switches, and all your port settings go with your virtual machines.

If you have virtual machines using traditional switches, you can easily move them to new distributed virtual switches. The rest of this article explains how to achieve this.

You can use the

Virtual Machine Roaming in the Cloud

March 28th, 2011 No comments

If you have a mobile phone and travel to other areas or countries, you can still use it to make and receive a call. Your phone number does not change. This is called roaming in the wireless telecommunications.

In the cloud environment, your virtual machine can “travel” around as well, maybe from one datacenter to another, from your enterprise to one of your service providers or the other way around, or from one service provider to another.

It’s relatively easy for a virtual machine

How to Enable or Disable Copy and Paste to Remote VM Console?

February 14th, 2011 No comments

In my previous post, I introduced how to change a virtual machine’s vmx file programmatically and promised to post a full sample in my presentation at VMware Parter Exchange 2011. Now that the conference is over, it’s time to post it.

The sample is based on guideline VMX03 in vSphere security hardening guide: disable copy/paste to remote console. To me, allowing copy and paste to remote console like vSphere Client is a nice feature which can save you a lot of time. When security is a concern, however, you may want to disable it.

I will not discuss when you should disable/enable it because it really depends on your requirements. In most cases, security and convenience contradict with each other. I leave it for you to decide the right balance, but show you how you can check the setting and change it here.

Like most samples I write,

How to Change VMX Programmatically?

January 31st, 2011 No comments

As most of you may have known, the vmx file is the most important file at the back of a virtual machine. It defines the configurations of a virtual machine for example virtual hardware version, devices, disk files, etc. That is why it owns the virtual machine icon when you look at all the files behind a virtual machine with either datastore browser in vSphere Client or VMware Workstation/Fusion.

Given the importance of the vmx file, we don’t recommend anyone to manually modify it given that messing it up may corrupt a virtual machine. You can change the content indirectly from GUI and APIs. If you can change the virtual devices of a virtual machine, its vmx file is changed accordingly.

Beyond basic configuration entries, the vmx file can be extended to hold key/value pairs. A vmx file is really a text file with many lines of key/value pairs. By extending it, you can add extra lines of key/value pairs at the end of the file. Keep in mind that you should NOT add any key that is duplicated with predefined keys like “virtualHW.version.” As you already noticed, the key has the “.” delimiter as namespace pattern. You can start with your own namespace to avoid possible name clash.

How to Differentiate Folders in vSphere

January 28th, 2011 2 comments

As we know Folder is a container object in vSphere. It’s used to hold other managed objects in a similar way as directory holding files in an OS. There is an interesting question asking in VI Java API forum on how to tell whether a folder is vmFolder or hostFolder. BTW, you don’t see these two folders displayed in vSphere Client.

The questioner guessed correctly that you can find out by a folder’s childType property. Here is the documentation in API reference on the possible values of the childType property:

How to Delete Virtual Machine With vSphere API?

January 18th, 2011 1 comment

This question was asked at VI Java API forum recently and has been answered by the community.

There should be a “Destroy_Task()”-Method for each Managed Object, so also Virtual Machines…. Cheers, Joerg

As  Jörg Lew has correctly pointed out the solution, I would like to elaborate a bit more here.

If you are using VI Java API, the method name is destroy_Task(). The code is as simple as:

Cloud Architecture Patterns: Cloud Broker

January 3rd, 2011 No comments

Intent

Provide a single point of contact and management for multiple cloud service providers and maximize the benefits of leveraging multiple external clouds.

Category

Structural

Motivation

When you are buying and selling stocks or other securities, you hire a broker to execute the trade on your behalf. One reason for that is convenience. You don’t need to take care of the details of placing orders and working with multiple stock exchanges, and whatever else is required to trade securities.

How about working with multiple cloud service providers? For sure, you can go online to any cloud provider as long as you have your credit card ready. But is the service provider the best fit for your requirements? Do you have a backup plan if you are not satisfied with your service provider? Can you easily switch among your service providers to minimize cost or maximize flexibility? If you are not sure, you may then need something like a cloud broker.

Solution