Archive

Archive for the ‘Virtualization’ Category

3 Ways to Get Hold of Managed Objects in vSphere

March 30th, 2010 No comments

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:

Categories: vSphere API Tags: ,

vSphere Inventory Structure Deep Dive

March 29th, 2010 4 comments

This blog digs into the vSphere inventory structure, and changes in vSphere 4 from VI. It explains the difference between ESX and vCenter inventory tree, why the inventory path you see from vSphere Client doesn’t work with API. Much of the content is adapted from my book VMware VI and vSphere SDK by Prentice Hall.

Inventory vs. Inheritance hierarchy

My previous blog introduced the object model of the vSphere API. The UML diagram there shows how different managed object types are structured in the inheritance hierarchy.

The inventory hierarchy is quite different. It shows how different managed object instances are associated. With this understood, you can easily navigate among different managed objects in inventory tree of both ESX and vCenter. It’s critical for programming vSphere API because navigating the inventory is the primary way to get hold of managed objects.

Categories: vSphere API Tags: ,

Demystifying 3 “View”s from VMware

March 23rd, 2010 6 comments

After I blogged the top 5 myths of vSphere API, William Lam suggested me to write a bit more on the views in his comments. If you haven’t followed him (@lamw) at Twitter yet, you may want to. His vGhetto Perl repository is one of the best resources for people who use VI Perl.

For sure, VMware loves the term “view”. As far as I know, there are 3 different ”views.” Two of them are for APIs; the last one is for the desktop product family. We are not going to talk about the product View in this blog. You can find more information at VMware web site.

Let’s instead focus on the two “Views” for developers: one is in VI Perl and .NET/PowerCLI; the other is part of the core vSphere API.

Categories: vSphere API Tags: , , , ,

Why Some vSphere Java API Methods don’t Work with Old Servers? A Story of Compatibility

March 15th, 2010 1 comment

Many of you already know there are some changes in the vSphere API from 2.5 to 4.0. The changes include 20+ new managed object types, additional properties (including sub-properties that embedded inside the first level properties), and several inheritance structure changes.

Several managed objects like Datastore became the subtype of ManagedEntity in vSphere 4, which is different from the hierarchy in 2.5 where it’s a subtype of ExtensibleManagedObject. The changes came for good reasons – we want permission control over these managed objects.

SimDK – A VMware vSphere Simulator

March 9th, 2010 5 comments

Just got the following email from Andrew Kutz (@sakutz) who wrote the famous VMware Infrastructure (VI) plug-ins whitepaper and created several other great projects like VMM.

David Marshall, Dave McCrory and I, as well as everyone else at Hyper9, are extraordinarily proud to announce SimDK – a VMware vSphere4 simulator which provides vSphere4 API-compatibility for official vSphere4 clients and other applications built using the vSphere4 SDK.. SimDK is an open source project available at http://simdk.sourceforge.net/. You can read more about this exciting announcement at http://akutz.wordpress.com/2010/03/09/simdk.

Categories: vSphere API Tags: ,

Vote for vSphere Java API at VMware Labs

March 9th, 2010 2 comments

Several smart bloggers (Eric Sloof, Justin EmersonIan Koenig, Alessandro Perilli) discovered the VMware Labs web site over the weekend. As many pointed out, it’s absolutely cool.

I actually knew it was going to be online this past weekend, but would like to get official announcement from the company before blogging it. The reason I knew the site to go live is because the vSphere Java API I created is one of the first 10 projects.

Categories: vSphere API Tags:

Lightweight Caching Framework in vSphere Java API 2.0

March 7th, 2010 5 comments

In vSphere Java API 2.0, I wrote a lightweight caching framework. It’s still experimental but has a great potential to greatly simplify your development work. Commercial companies already use it in their products.

The motivation behind this framework is simple – instead of keep polling the changes from the server side, you keep a local cache that is made as fresh as possible. The View in the vSphere Perl toolkit is one way to do. It caches all properties of a managed object despite the fact that you don’t need that many at all.

The caching framework in vSphere Java API takes another approach. You tells it what managed objects and what properties you want to be cached. After that, the caching framework does its best to read the properties and keep them as fresh as possible.

Architecturally the caching framework is totally separated from the core of the API. You can take it away without any impact on the rest of the API. This is quite different from other toolkit.

Have enough introduction? Let’s take a look at sample code:

Categories: vSphere API Tags: ,

Using vSphere Java API in Jython and Other JVM languages

March 5th, 2010 2 comments

As a by-product, the vSphere Java API makes Jython programming a lot easier. The following is a very simple sample written in Jython to print out the name of the first virtual machine in inventory.

    from java.net import *
    from com.vmware.vim25.mo import *

    si= ServiceInstance(URL(“https://sjin-dev1/sdk”),\
    “root”, “password”, True)
    rootFolder = si.getRootFolder()
    vms = InventoryNavigator(rootFolder) \
    .searchManagedEntities(“VirtualMachine”)
    print “Hello ” + vms[0].getName()
    si.getServerConnection().logout()

As you can see, it really brings in the benefit of VI Java API into Python community at almost no extra cost.

Categories: vSphere API Tags: ,

5 Easy Steps Using vSphere Java API

March 4th, 2010 2 comments

In my previous blogs, I have introduced the vSphere API object model, vSphere Java API architecture. I assume you’ve run through the 5 minute Getting Started Tutorials with HelloWorld sample.

Now, let’s take a look on how to use the API in general.

1. Always starts with a ServiceInstance with URL/username/password, or URL/sessionID. For example,

ServiceInstance si = new ServiceInstance(new URL(urlStr), username, password, true);

2. From the ServiceInstance object, you can:

Categories: vSphere API Tags: ,

vSphere Java API Architecture Deep Dive

March 3rd, 2010 2 comments

In my previous blog, I talked about the object model of the vSphere API. Many people like the UML diagram that illustrates how the managed objects are inherited from each other.

Following that blog, I will introduce the object model of the open source Java API that is built on top of the Web Services, as well as some key design decisions I made while designing the API.

The following UML diagram is extracted from the overall model but adds much more details with properties and methods. If you can understand this diagram, you can then easily understand all other managed object types.

Trying Self Paced Lab without Going to PEX 2010

March 2nd, 2010 No comments

I mentioned the vSphere API self paced lab at PEX in my previous blog. Not all the people who are interested in learning the API made it to PEX last month. A reader asked me when it can be online in his comment.

Here is the VI Java API part in the tutorial. We had the environment set up all together for you in the PEX lab including the Eclipse and all the related jar files. So it’s very easy to get started there. Without going to PEX, you need to do something extra by yourself. But that is not too hard at all. I promise it won’t take you much time at all. To get the basic one done, you probably need 5 to 30 minutes depending on your familiarity with Java.

Ready to learn?

Top 5 Myths about VMware vSphere API

February 28th, 2010 10 comments

If you have trouble to understand vSphere API when you first use it, you are definitely not alone. I had the same trouble when I first used it a while back.

Some of the troubles come from the disconnect between conventional programming model and that of vSphere API. In this blog, I summarize the top 5 myths about vSphere API based on my experience and the questions I see in the VMware community forum and vSphere Java API forum:

  1. Non-existing Managed Objects
  2. Pervasive PropertyCollector
  3. Short-Lived Task Object
  4. “Weak” HostSystem
  5. “Un-documented” View

Let’s examine each of them one by one.

Object Model of VMware vSphere API: A Big Picture in 2 Minutes

February 27th, 2010 22 comments

When I start to use a new API/SDK, I always look for the object model diagram before digging into the API Reference. With that, I can have a good overview of the API, from the concepts to the structure. This can save a lot of time.

Unfortunately, we don’t find such a object model diagram in any official document. The following is the UML diagram from my book VMware VI and vSphere SDK.

VQL – A Domain Specific Language for Virtualization

February 26th, 2010 No comments

Last summer, Reflex VP engineering Aaron Bawcom visited VMware campus. He is one of the authors of Virtualization For Security: Including Sandboxing, Disaster Recovery, High Availability, Forensic Analysis, And Honeypotting.

During our talk, Aaron told me a secret project called VQL. Because it’s a secret, I didn’t talk about it to anyone. Just before the PEX 2010, we exchanged emails about the VQL. Aaron told me it’s already shipped. So it’s time to broadcast it.

VQL is a DSL that looks like SQL, easy to understand and easy to use. Unlike SQL on data, it’s on virtual resources in vSphere environment. The following is a quick sample. It gets back the VMs installed with SQL servers with verions newer than 9.2 and they are running 10 minutes ago.

SQL Server and VersionMajor >= 9 and VersionMinor >= 2 project vm at 10 minutes ago

Categories: vSphere API Tags: , ,

3 Easy Ways Connecting to Your VM in Private Cloud

February 24th, 2010 30 comments

Several folks asked me about how to use vSphere(VI) Java API to connect to a VM running on vSphere. The quick answer is vSphere Java API is not designed for this. You will need VMware Remote Console, browser plug-in, remote desktop/VNC, SSH client etc. However, it can help you to get the information required by the console or plug-in. Tal Altman from CISCO suggested that it be a topic for doublecloud.org. Here it is.

There are 3 ways to connect to the VM from your client side outside the vSphere and Web Access which have built-in support for console access.

  1. Using VMware Remote Console which is a standalone application
  2. Using browser plug-in to either IE or Firefox (Note: this is NOT supported by VMware. Please don’t call the company tech support for this.)
  3. Using Remote Desktop, VNC or SSH

The first two connect to the ESX host, and work even there is no guest OS installed on the VM. The last one assumes you have guest OS installed, and have IP network and server components in place already.

Note that these 3 ways work for the VMs in the public cloud as well if the related ports are open in your firewall. It is, however, not the case for most enterprises, therefore I particularly say it’s for VMs in private cloud. If you don’t have firewall issue, feel free to give it a try with public cloud as well.

Let’s go over one by one in details and see how vSphere Java API helps.

VIJava Browser – A Great Tool To Recommend!

February 22nd, 2010 19 comments

While browsing the project home of VI Java API, I found a link to a great tool contributed by pitchcat. It is a standalone Java application that shows managed objects and data objects in a tree hierarchy, and all the methods attached to a managed object.

I highly recommend it to all the VI Java API developers. Why? Although you can get similar information from MOB, vijava browser gives you an overview of all the managed objects and clear paths to any managed objects or data objects.

Categories: vSphere API Tags: , , ,

Automatically Generate Your Java Code With Onyx?

February 6th, 2010 2 comments

During last Friday VMware beer bash, I bumped into Carter Shanklin. He told me he’s ready show off how his Onyx project can help Java developers using VI Java API at Partner Exchange next week in Las Vegas. If you will be there, be sure to attend his session TEXIBP1007 – also known as “Getting Stoned with ‘Project Onyx’” on Thursday at 11:30.

The Mythical Sessions in vSphere and VI

February 5th, 2010 7 comments

In my previous blogs, I talked about session management for scalability and best practices (#9). In this one, I am going to drill down to the bottom.

To your surprises, there are two types of sessions involved in vSphere SDK:

  • HTTP Session. It’s used to identify a client and tracked by the cookie in HTTP header. Once you login the server, all the successive requests have to carry the cookie header similar as follows

vmware_soap_session=”5229c547-1342-47d1-e830-223d99a47fba”

  • User Session. It’s used to identify a login session of a particular user. You can use SessionManager to find out more the details of the current user and other login users from the UserSession data object. The key in the UserSession is in the same format as the HTTP session, but you should never confuse them, or use them interchangeably.

4 Ways to WIN $2,500 Prize With vSphere Java API

February 4th, 2010 3 comments

You may have read blogs from my colleagues Mike DiPetrillo, Duncan Epping about the VMware Script-O-Mania contest. The prizes are $2,500 (1st), $1,000 (2nd), and $500(3rd) respectively. The contest ends in March 15, 2010. So act quickly!

“Wait, how can I WIN the prizes?”

Well, first of all, you want to read carefully the criteria. Note that your script is for System Administrators with ESXi. So it could be for initial server set up, health monitoring, trouble shooting, reporting auditing, or anything else that is cool and creative. I suggest you talk to system administrators what REAL PAINS they have, and how they would like to fix the problems.

When you are clear what problems to solve, then let’s move on.

If you are already familiar with PowerCLI and RCLI, you should probably stick with them. You can get helps from VMware Developer Community.

If not, open source VI Java API can help you!

Here are 4 ways the API can do for you to win the $2,500:

Introducing A Tiny Yet Powerful API to Manage and Automate vSphere

February 3rd, 2010 8 comments

In yesterday’s blog, I talked about a little known secret of vSphere MOB – the invisible embedded XML in the HTML pages. To take advantage of the secret, I created a client side REST API which was shipped in VI Java API 2.0.