WilliamLam.com

How to quickly deploy new CoreOS Image w/VMware Tools on ESXi?

by // 14 Comments

deploy-coreos-with-vmware-tools-on-esxi Thanks to a conversation I had this morning with a Twitter user @BOK, I learned that CoreOS has just recently published a new CoreOS Alpha Image (v490.0.0) that now includes the Open VMware Tools package. In addition, the new image also now uses the optimized VMXNET3 network adapter. From our chat, it looks like this update is not available in the insecure or VMware Fusion image and I can only guess that these images may eventually get deprecated or removed completely in favor for the newer VMware image which can both run on ESXi as well as hosted products like VMware Fusion/Workstation.

@BOK also shared with me a modified version of my script that I initially created to automate the deployment of CoreOS onto ESXi. The original workflow had to be slightly modified as the new image is only available as bz2 (bunzip2) and ESXi does not contain the bunzip2 utility. This means there are now two steps: first is to extract the VMDK and upload to ESXi datastore which is going to be done manually and you can run the script which will automatically convert the VMDK to the proper format and register the VM in ESXi.

I was thinking about how I could simplify this process, even though it is just a couple of extra commands, I always like to see how I can make something easier to consume and reducing the complexity if possible. I of course decided to create a new script called deploy_coreos_on_esxi2.sh which now runs outside of the ESXi Shell. The script requires a UNIX/Linux system that has the bunzip2 utility and will automatically download both the VMX and VMDK file, perform the extraction and then upload it to ESXi host using an HTTP API provided through the vSphere Datastore. Lastly, it auto-generates the configuration shell script that will run over SSH to the ESXi host (SSH is still required) which will perform the same set of operations as my previous script did.

Note: You will be prompted to enter the ESXi root password when it tries to run the script remotely on the ESXi Shell, there is a timeout for 120seconds in case you step away from the console.

Prior to running the script, you will need to edit the following 7 variables:

  • ESXi_HOST
  • ESXI_USERNAME
  • ESXI_PASSWORD
  • ESXI_DATASTORE
  • VM_NETWORK
  • VM_NAME

Here is a screenshot of running the script from my Mac OS X desktop:

install-core-os-with-vmware-tools-on-esxi-0
Once the CoreOS VM has fully booted, we can take a look at our vSphere Client and we should see that VMware Tools is in fact running and we can see the IP Address automatically being displayed in the UI:

install-core-os-with-vmware-tools-on-esxi-1
The really nice thing about having VMware Tools running in the CoreOS image, is that you can use VMware's Guest Operations API to be able to perform operations within the guest which are proxied through VMware Tools and can be quite handy, especially if networking is not available or you want to go through a single management interface such as using the vSphere API.

govmomi (vSphere SDK for Go), govc CLI & Kubernetes on vSphere

by // 15 Comments

go-sdk-for-vsphere
One of the exciting announcements that was made last week at VMworld was the joint partnership between Docker, Google, Pivotal and VMware. Paul Strong (Office of the CTO) wrote a great blog post Better Together – Containers are a Natural Part of the Software-Defined Data Center where he goes into more details about the partnership. The really neat part of the announcement which I think some people may have missed is that this was more than just an announcement. There are actually active projects currently being worked on, most notably a working prototype for a Kubernetes vSphere Provider.

For those of you who are not familiar with Kubernetes, it is an open-source project that was started by Google which provides Container Cluster Management. You can think of Kubernetes as a placement engine/scheduler for Containers, similar to how vSphere DRS is responsible for scheduling Virtual Machines. The Kubernetes vSphere Provider allows you to run a Kubernetes Cluster on top of a vSphere based infrastructure and provides a platform for scheduling Docker Containers running on top of vSphere.

Kubernetes is completely written in Go (short for Golang), a programming language developed by Google. To be able to easily integrate with Kubernetes, a Go library needed to be written for the vSphere API and hence govmomi was born! Similar to pyvmomi and rbvmomi which are vSphere SDKs for Python and Ruby respectively, govomimi is the vSphere SDK equivalent for Go. The govmomi project is an open source project lead by VMware and you can find the Github repository at https://github.com/vmware/govmomi.

In addition to govmomi, I also learned about a neat little CLI that was built on top of the SDK called govc (currently an Alpha release) which provides a simplified command-line interface to a vSphere environment leveraging govmomi. You can find the source code under the govmomi Github repository https://github.com/vmware/govmomi/tree/master/govc. The Kubernetes vSphere Providers leverages govc to be able to orchestrate the deployment of a Kubernetes Cluster on top of vSphere leveraging the vSphere API.

To use govc, you will need to ensure you have Go 1.2+ installed on your system. Here are the steps on installing Go and govc

Step 1 - Download the latest Go package installer for your OS here and once you have Go installed, you can verify that everything is working by running the following command:

go version

Screen Shot 2014-09-03 at 4.00.10 PM
Step 2 - Setup your build environment by running the following commands:

export GOPATH=$HOME/src/go
mkdir -p $GOPATH
export PATH=$PATH:$GOPATH/bin

Screen Shot 2014-09-03 at 4.02.17 PM
Step 3 - Check out govc source code by running the following command:

go get github.com/vmware/govmomi/govc

Screen Shot 2014-09-03 at 4.03.00 PM
At this point, govc has been installed. You can now connect to either a vCenter Server or ESXi host. The easiest way is to specify the vSphere API endpoint and credentials is by setting a couple of environmental variables, so you do not have to specify it on the command-line.

Step 4 - Run the following command and specify the username, password and either the hostname or IP Address of your vCenter Server or ESXi host:

export GOVC_URL='https://[USERNAME]:[PASSWORD]@[ESXI-OR-VCENTER-HOSTNAME-OR-IP]/sdk'

Step 5 - To verify that everything is working, you can run the following command to query the endpoint you have connected to:

govc about

Screen Shot 2014-09-03 at 4.45.06 PM
If everything was successful, you should see some basic information about the vSphere API endpoint you have connected to. In the example above, I am connected to a VCSA (vCenter Server Appliance). The govc CLI is quite similar to RVC with commands broken up into various namespaces. However, one feature that is not there today is the ability to tab complete the commands which is something I just love about RVC!

You can also just run "govc" and it will provide a list of available commands:
Screen Shot 2014-09-03 at 4.45.19 PM
You can get more details about each command by specifying --help command, here is an example of the host.info
Screen Shot 2014-09-03 at 4.45.58 PM
To get information about one of my ESXi hosts, I need to specify --host.ip option along with the IP:
Screen Shot 2014-09-03 at 4.46.20 PM
As you can see from the screenshot above, some basic information is displayed about my ESXi host which is running on a Mac Mini. If you would like to learn more about govc, I highly recommend you check out the govc repository on Github which has additional documentation. You can also file any bugs or feature requests you would like to see on the project page.

At this point you are now ready to proceed to the next steps which is to setup Kuberentes and deploy a Kubernetes Cluster onto your vSphere environment. Unfortunately I ran into a problem while going through the Kubernetes deployment and I did not know where to go next and decided to file a Github issue here. To my surprise, I immediately got a response back from the VMware Engineers who are working on the project. I had a couple of email exchanges with the team to debug the problem. It looks like we found the culprit and I was able to get Kubernetes up and running. There are a couple of minor caveats which I will explain in more detail in Part 2 of this post and walk you through the steps of deploying a Kubernetes Cluster running on top of vSphere.

How to quickly deploy CoreOS on ESXi?

by // 1 Comment

deploy-coreos-on-esxiThere has been a tremendous amount of buzz lately regarding Docker, a platform that allows developers to easily build, deploy and manage Linux Containers. Docker can run on variety of Linux Distributions, one that has been quite popular lately is a new Linux Distribution called CoreOS.

CoreOS is actually a fork of Google's ChromeOS and was designed to run next generation workloads similar to those at Google and Facebook. A major benefit of CoreOS is the minimal footprint the base operating system consumes which allows for maximum resource utilization for the Container workloads.

Having heard so much about Docker and CoreOS, I figure this would be a great opportunity to explore and learn about a new technology which I always enjoy when I get the time. I know Duncan Epping has written an article on how to run CoreOS on VMware Fusion, but since I primarily work with vSphere, I wanted to run CoreOS on ESXi. The first place I went to was the CoreOS documentation and there is a section for VMware. After going through the instructions, I found the process to be quite manual and potentially requiring additional tools as a simple OVF/OVA for CoreOS did not exist.

I figured I could wrap the process in a very simple shell script that only required a couple of input parameters from the user based on their environment and the script would auto-magically handle the deployment. I created a shell script that would run on the ESXi Shell called deploy_coreos_on_esxi.sh

Note: The script assumes you can connect directly to the CoreOS website to download the zip directly onto the ESXi host.

There are three variables that you will need to edit prior to running the script:

  • DATASTORE_PATH - The full path to the Datastore to deploy CoreOS onto (e.g. /vmfs/volumes/datastore)
  • VM_NETWORK - The name of the vSphere Network to connect the CoreOS VM to
  • VM_NAME - The name of the CoreOS VM

Once you have finished editing the script, you just need to scp to your ESXi host and run the script using the following command:

./deploy_coreos_on_esxi.sh

Here is screenshot of running the script:

deploy-coreos-on-esxi-0
Once the script has completed, you should see a new CoreOS VM on your ESXi host and if you have DHCP, you should also see an associated IP Address in the VM Console:

deploy-coreos-on-esxi-1
Once the CoreOS VM is booted up, you use the SSH key that was included in the zip file, by default it is also extracted into the CoreOS VM directory. You can SSH into the VM by running the following command:

ssh -i insecure_ssh_key core@IP-ADDRESS-OF-COREOS-VM

Once logged in, we can run "docker images" to see a list of Containers. As you can see that there is only one and we can connect to that Container by running the "toolbox" command which will pull down the latest and then connect to that Container as seen in the screenshot below.

deploy-coreos-on-esxi-3
I was hoping that I could also get VMware Tools installed within the CoreOS VM, but I was not able to get SSH working within the Toolbox as stated in the Install Debugging Tools documentation. I may need to tinker around a bit more with CoreOS.

If you are interested in other methods of deploying CoreOS, be sure to check out CoreOS's documentation.

Additional Resources: