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In a previous post, I blogged about a tutorial on using the open source VI Java API in Groovy by Aaron Sweemer. Two weeks later, he wrote a new tutorial Easy vSphere Web Apps with Grails and the VI Java API.

In his new tutorial, Aaron introduced detailed steps in how to use the VI Java API for a simple web application with Grails framework. The web application displays a web page that lists all the virtual machines with the corresponding guest OS names and whether they support multiple snapshots.  Read more... (193 words, estimated 46 secs reading time)

Recently there were questions in the vSphere Java API forum on how to clone a new session from an existing one. Although vSphere Java API wraps around the basic Web Services API cloneSession() method, simply calling the method doesn’t get what you want.

Why? The signature of cloneSession() is as follows. It returns UserSession, which is embedded inside ServiceInstance managed object in vSphere Java API. While using the API, you always starts from the ServiceInstance.

public UserSession cloneSession(String cloneTicket) throws InvalidLogin, RuntimeFault, RemoteException;

In vSphere Java API, the ServiceInstance and UserSession have one to one mapping. Without a new ServiceInstance around the new UserSession, the UserSession is not much helpful.

Luckily, we got yet another contribution from Eric Forgette who works at NetApp. The contributed code includes a new overloaded method cloneSession() method to return a ServiceInstance object.

As I described before, we’ve been trying very hard to keep the vSphere Java API as close to the basic Web Services as possible. In this case, we decided to break the rule a little bit for good reasons, mainly for usability.  Read more... (409 words, estimated 1:38 mins reading time)

Every time I google for VI(vSphere) Java API, I get something new. Here is yet another one I just found. It’s a blog article Easy VMware Development with VI Java API and Groovy by Aaron Sweemer. By reading his blog site, I came to know Aaron is actually my colleague at VMware working as a Sr. System Engineer in Cincinnati Ohio. He is the principal blogger at Virtual Insanity.  Read more... (211 words, estimated 51 secs reading time)

As I discussed extensively in my book, the PropertyCollector is very powerful yet not easy to use. There was a question posted at vSphere Java API forum related to the property collector which I think worths sharing here. Although it’s found using vSphere Java API, but it really goes beyond the API to the vSphere API itself.  Read more... (307 words, estimated 1:14 mins reading time)

Having answered many questions about IP addresses of virtual machines at different occasions, I still see more are coming. I think it’s time to write a blog about it. Hopefully people would search the Internet before raising the question.

First of all, there is a big confusion on the relationship of IP addresses and virtual machines. Many people tend to associate IP addresses with virtual machines, and want to retrieve/change the IP address of a virtual machine.

In fact, a virtual machine is very much like its physical counterpart. It does not have an IP address by itself. In other words, an IP address is NOT an intrinsic attribute of a machine, either virtual or physical. It might have one or more only after an OS is installed. In most cases, it does have one or more IP addresses, which gives the impression that every machine has an IP address.

A virtual machine does have intrinsic attributes such as MAC addresses if NIC cards are configured. Unlike its physical counterpart, a virtual machine’s MAC address can be re-configured. Some software vendors rely on MAC addresses to lock down their licensed software on particular machines. This mechanism can be, therefore, compromised in virtual environments.  Read more... (543 words, estimated 2:10 mins reading time)

While searching Twitter on “vSphere Java”, I found my presentation available today online at InfoQ (many thanks to @arm1433 and @toya256ForRSS). It has both video and slides for more than one hour. The voice was not quite clear in the first one or two minutes. After that it’s pretty good.

This presenation is a complete overview of the open source vSphere Java API. Because the audience then was new to virtualization, the first several minutes covered a little virtualization basics. You can scroll over if you know virtualization already.  Read more... (200 words, estimated 48 secs reading time)

This article is based on a similar one at vSphere Java API home page. At that time, one of VMware community members sent me an email for samples of using OvfManager APIs. Then I went to office on a Saturday writing two samples, which have been validated by several folks as “working” samples.

The purpose of the samples are to illustrate the vSphere APIs. Let’s take a look at them one by one.

First, ExportOvfToLocal.java. This sample shows how to download either a VM or vApp to your local machine. The typical flow is:  Read more... (2438 words, estimated 9:45 mins reading time)

• Find the VM or vApp
• Call their exportVm() or exportVApp() methods and get HttpNfcLease
• Set lease time out
• Wait for HttpNfcLease until it’s ready
• From the HttpNfcLease.info property, find the all URLs from which you download the vmdk files
• Call OvfManager.createDescriptor() API to create the content of ovf and save it to a file along with downloaded vmdk files.
• Release the lease by calling httpNfcLeaseComplete() method

This article introduces you the basic model and terminologies in vSphere security management, for example, privileges, permissions, roles, and how they are related to each other to secure vSphere. It helps you to better manage the vSphere and program the vSphere API. Much of the content is based on my book VMware VI and vSphere SDK by Prentice Hall.

In vSphere, the security model consists of three types of components: privileges, roles, and permissions.

Privileges

A privilege is the basic individual right required to perform an operation. It is statically defined and never changes in a single version of a product. Given the many operations in VI, there are many privileges (for example, the privilege to “power on a virtual machine”). These privileges are represented as strings separated by dots, such as VirtualMachine.Interact.PowerOn.

The operations and privileges are not one-to-one mapping. Many operations do share common privileges like System.View. Therefore, there are many fewer privileges defined than methods. In some exceptional cases, a method requires different privileges depending on the target it operates on and the nature of the operation. The CloneVM_Task() method, for example, requires VirtualMachine.Provisioning.Clone for cloning from one virtual machine to another, VirtualMachine.Provisioning.DeployTemplate for cloning from a template to a virtual machine, and so on.

Roles

The role groups privileges from a user’s perspective. A role is normally named and defined for a group of people who have common responsibilities in the system (for example, administrators). Each role can include zero to multiple privileges. The extreme cases are the predefined “Admin” roles, which by default, includes all the privileges and the NoAccess role, which includes no privileges.  Read more... (758 words, 1 image, estimated 3:02 mins reading time)

Performance monitoring is a critical aspect of vSphere administration. This article introduces you the basic concepts and terminologies in vSphere performance management, for example, performance counters, performance metrics, real time vs historical statistics, etc. Much of the content is based on my book VMware VI and vSphere SDK by Prentice Hall.

Once you understand these basics, the related tools and APIs should be relatively easy. If you are already familiar with vSphere Client performance monitoring or esxtop, they help as well.

Performance Counter

A performance counter is a unit of information that can be collected about a managed entity. PerfCounterInfo data object, shown in Figure 1, represents a performance counter. The property key is an integer that uniquely identifies a performance counter, like a primary key of a table in SQL database, and nothing more. There is no guarantee for a performance counter to have a fixed number. In fact, the same performance counter can have different values in ESX and VirtualCenter. Even for the same type of server, the number could change from version to version. Do not use it outside the context of the server you connect to.

Figure 1 PerfCounterInfo data object

The performance counter can be represented by the following dotted string notation:  Read more... (1520 words, 2 images, estimated 6:05 mins reading time)

If you have ever used vSphere Web Service API, you must have known that there is no managed object but ManagedObjectReference object. Understanding it helps deepen your understanding of the vSphere API.

Honestly, the ManagedObjectReference is a little confusing by itself. It is in fact a data object but represents a managed object. You can think of a MOR as a pointer in some sense because it’s used to uniquely identify a managed object. Even better, you can think of the “type” and “value” defined in the MOR in the SQL way. The type is like a table name, and the value like the primary key which can uniquely identify a managed object in its type.

MOR is really intended to be used by program and should be carefully limited to the scope of where it comes from. That is why it’s hidden from application developers in vSphere Java API.

Anyway, let’s see how to get hold of MOR objects:  Read more... (583 words, estimated 2:20 mins reading time)