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Early Xmas gift from VMware - pyVmomi (vSphere SDK for Python)

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For vSphere customers and partners who use the Python programming/scripting language, Christmas may have just arrived early. I just found today, VMware has published an initial release of their vSphere SDK for Python called pyVmomi on Github this past weekend. A Python-based SDK has always been a very popular feature request among customers and partners that I have spoken with in the past. It looks like VMware Engineering has heard you loud and clear and have been working hard to get this released.

pyVmomi Github Repository:
https://github.com/vmware/pyvmomi

pyVmomi Pypi package:
https://pypi.python.org/pypi/pyvmomi

One of the nice things about releasing pyVmomi on Github versus trying to package it with a particular vSphere release is that the larger VMware community can contribute to the project as well as more frequent updates from VMware. This has also been quite successful for another popular VMware SDK called rbvmomi (vSphere SDK for Ruby) which is seeing a huge uptick with RVC (Ruby vSphere Console) which is built on top of rbvmomi and is a great tool for managing and troubleshooting VMware VSAN.

In this first release, you will notice there is a limited amount documentation and samples exercising the various capabilities of vSphere and you will see further enhancements in these areas with future updates. If there are specific things you would like to see or samples that you think would be useful to have or that you have built, feel free to file an issue or send pull requests to the pyVmomi Github.

If you wish to quickly get started, you can install pyVmomi using a variety of methods including pip, easy_install and pypi package. Below are the steps I took to install pyVmomi on my Mac OS X system using pip and git.

Step 1 - Install pyVmomi using pip by running the following command:

sudo pip install pyvmomi

Step 2 - Clone the pyVmomi Github repo to your system using Git by running the following command:

git clone https://github.com/vmware/pyvmomi.git

After the above command, you will have a folder called pyVmomi which contains the source code as well as the two sample scripts. You can contribute back if you create additional samples or enhancements to pyVmomi by simply sending a pull requests.

Try the getallvms.py sample run the following command:

python sample/getallvms.py --host mini.primp-industries.com --password [PASS]

To try the poweronvm.py sample run the following command:

python sample/poweronvm.py --host mini.primp-industries.com --password [PASS] --vmname [VM]

Hopefully we will see many more samples from VMware as well as from our customers who will be using the new SDK. If there is anything that is missing or things you would like to see, feel free to file an issue on pyVmomi Github repository.

Poor man's traceroute for ESXi

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There was a question today on the VMTN community forum about traceroute and ESXi. The user was troubleshooting a networking issue and logging into Tech Support Mode (Busybox Console) of ESXi, had noticed this common networking utility was not available. Since the user was working in a production environment, a re-compilation of a custom Busybox applet was out of the question and most likely unsupported by VMware. The user had to explore other avenues of troubleshooting, or did they have to?

It may not be well known, but within the Busybox Console, a Python interpreter is installed and accessible with a limited set of modules. Armed with this fact, you can actually create your own "poor man's traceroute" which gave you functionality similar to that of the actual traceroute/tracert implementation. This "poor man's" version was dubbed by a blog article I had found online (sorry, no ghetto in this name) by Leonid Grinberg - Learning by doing: Writing your own traceroute in 8 easy steps. The author goes into extreme detail providing step by step instructions on his python implementation of traceroute. Leonid provides a fully functional script at the end of his blog post, but he does caveat the following statement at the end:

This is actually not quite how the real traceroute works. Rather than checking the IP addresses of the hosts and stopping when the destination address matches, it stops when it receives a ICMP “port unreachable” message, which means that the host has been reached. For our purposes, though, this simple address heuristic is good enough.

This was definitely another alternative if one needed functionality similar to that of traceroute. I used the author's polished version of traceroute.py and scp'ed the script onto an ESXi host. It ran just as well as the real traceroute on the classic ESX Service Console.

Though this may not have solved the original network issue, it is important to know what utilities you have at your disposal, even if it is not the actual tool that you are familiar with. There is always more than one way to do something and it is always good to know a few.

VMware does limit the number of "common" UNIX/Linux utilities that are bundled within the Busybox applet and based on demand and feature requests, we may see future utilities added to Tech Support Mode. One example is the release of vSphere 4.1, we saw the addition of nc (netcat) and tcpdump which are invaluable troubleshooting utilities for a vSphere admin. If there are other utilities that you feel should be included in the default Busybox applet, be sure to submit your feedback to either your VMware rep or file a feature request.