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Auditing vMotion Migrations

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I saw an interesting question this week about auditing vMotion events and the number of times a VM has migrated to a particular ESX(i) host for license compliance. You can view this information using the Task/Events in your vCenter Server but you can also extract out the various types of events using the EventManager in the vSphere API. You will be able to go as far back in time as your vCenter Server's database retention policy allows you to. We will be searching for the VmMigratedEvent Event which will include variety of information including the source and destination host for the VM. The destination host will only be populated upon a successful vMotion.

Of course I had to write a script to help automate this, so here is a vSphere SDK for Perl script called getNumberOfvMotions.pl that accepts the name of an existing VM and will return the number of vMotions that has been performed on the VM as well as the list of destination hosts and the number of times it has migrated to those hosts. You will need a system that has the vCLI installed or you can you use vMA.

Note:  If you want to look at past vMotion for a VM that no longer exists, this is still possible, but you will need to parse the "message" within the Event as you can no longer look up that VM object in vCenter.

Here is an example of the script running:

You can easily modify the script to audit all VM's in your environment or just use a simple "for" loop to go through a set of VM's you are interested in, but I will leave that as an exercise for you.

How to Create Bootable ESXi 5 ISO & Specifying Kernel Boot Options

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This week I helped to answer a few questions about creating your own ESXi 5 bootable ISO along with automatically using a static IP Address when the custom ISO first boots up. Although all this information is available via the vSphere documentation, it may not always be easy to put all the pieces together and thought I share the steps for others to also benefit.

You will need access to a UNIX/Linux system and a copy of the base ESXi 5 ISO image. In this example I will be using VMware vMA and VMware-VMvisor-Installer-5.0.0.update01-623860.x86_64.iso and walk you through two different configurations. We will also be referencing the vSphere documentation Create an Installer ISO Image with a Custom Installation or Upgrade Script and Kernel Boot Options.

Create ESXi 5 Bootable ISO w/Remote ks.cfg:

In this configuration, we will create a custom ESXi ISO that will boot with a static IP Address and use a remote ks.cfg (kickstart) configuration file.

Step 1 - Mount base ESXi ISO using the "mount" utility:

$ mkdir esxi_cdrom_mount
$ sudo mount -o loop VMware-VMvisor-Installer-5.0.0.update01-623860.x86_64.iso esxi_cdrom_mount

Step 2 - Copy the contents of the mounted image to a local directory called "esxi_cdrom":

$  cp -r esxi_cdrom_mount esxi_cdrom

Step 3 - Unmount the ISO after you have successfully copied it and change into the esxi_cdrom directory

$ sudo umount esxi_cdrom_mount
$ cd esxi_cdrom

Step 4 - Edit the boot.cfg and specifically the "kernelopt" line to not use the weasel installer but kickstart and also specifying the remote location of your ks.cfg. To get more details on the various kernel boot options, please take a look at the vSphere Boot Options documentation above.

You will also need to specify the static IP Address you wish to have the host automatically use when the ISO first boots up on the same line.

Step 5 - Once you have finished your edits and saved the boot.cfg, you will now change back to the parent directory and use the "mkisofs" to create your new bootable ISO. In this example, we will name the new ISO "custom_esxi.iso":

$ sudo mkisofs -relaxed-filenames -J -R -o custom_esxi.iso -b isolinux.bin -c boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table esxi_cdrom/

You now have a new bootable ESXi 5 ISO called "custom_esxi.iso" which will now automatically boot up with the specified static IP Address and install based on the ks.cfg that was specified.

Create ESXi 5 Bootable ISO w/Local ks.cfg:

Similar to the above configuration, we will create a custom ESXi ISO that will boot with a static IP Address but use a local ks.cfg (kickstart) configuration file that will be included within the custom ISO.

Step 1 through 3 is exactly the same as above

Step 4 - By default, a basic ks.cfg is included in the ESXi 5 ISO in /etc/vmware/weasel/ks.cfg and we will create a custom *.tgz file that will include our ks.cfg within the ISO. First off by creating a temporary directory which will be used to store our ks.cfg:

$ mkdir -p temp/etc/vmware/weasel

Step 5 - Copy your ks.cfg file into the temp/etc/vmware/weasel:

$ cp ks_custom.cfg temp/etc/vmware/weasel

Step 6 - Create a *.tgz file containing the path to our ks.cfg using the "tar" utility. In this example, we will called it customks.tgz:

$ cd temp
$ tar czvf customks.tgz *

Step 7 -  Copy the customks.tgz from temp directory to your esxi_cdrom directory:

$ cp temp/customks.tgz esxi_cdrom

Step 8 -  Change into the "esxi_cdrom" directory and edit the boot.cfg just like the above, but we will be using the "file://" stanza to specify the path to our ks.cfg, static IP Address as well as adding our customks.tgz to the module list to ensure that it loads up which contains the actual ks.cfg file that is called in the boot.cfg.

Step 9 - Same as Step 5 above, you now just need to run the "mkisofs" utility to create your bootable ISO.

You now have a new bootable ESXi 5 ISO called "custom_esxi.iso" which will now automatically boot up with the specified static IP Address and install based on the ks.cfg that is included within the ISO.

VM Provisioning on Datastore Clusters in vSphere 5

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Last year I wrote an article called Automating Storage DRS & Datastore Cluster Management in vSphere 5 and I provided a pretty comprehensive vSphere SDK for Perl script to help administrators automate Storage DRS configurations. These past few months I have noticed an increase in interest on the VMTN developer forums relating to Storage DRS. Majority of the questions has been related to which vSphere API methods to use and how to use these methods for cloning VMs to datastore clusters.

If you have cloned a VM before, the underlying vSphere API method being used is the CloneVM_Task(), but when cloning a VM to a datastore cluster, a different API must be used.

In vSphere 5, VMware introduced several new API methods in the StorageResourceManager and the two specific ones relating to provisioning VMs are RecommendDatastores() and ApplyStorageDrsRecommendation_Task(). The process to clone a VM to a datastore cluster is a two step process:

  1. Call RecommendDatastores() which accepts very similar input as the CloneVM_Task(). In addition, you need to specify the datastore cluster also known as a Storage Pod in the vSphere API as well as the "type" (create, clone, relocate, reconfigure), in this example we will be performing a clone operation. This method will then generate a recommendation on where to place the VM which is based on the SDRS placement engine. No provisioning will occur at this point, just a placement recommendation.
  2. To perform the actual provision of the VM, you will need to call ApplyStorageDrsRecommendation_Task() which accepts a recommendation ID that was generated from the first step. Once the recommendation is applied, the provisioning of the VM will start just like it did when you called the CloneVM_Task().

Note: The RecommendDatastores() will return multiple recommendations, the best one will be first entry in the array. This is the same algorithm used when performing this same operation in the vSphere Client, it also selects the first recommendation.

Now that we understand how the APIs work, let's take a look at how we can leverage this in a script for some automation! Here is a simple vSphere SDK for Perl script called datastoreClusterVMProvisioning.pl which allows you to clone an existing VM onto a datastore cluster. You will need a system that has vCLI 5.0 installed or you can use VMware vMA 5 to run the script. You will also need to connect to a vCenter Server 5 for all SDRS operations.

The script requires 4 input parameters:

  • vmname - Name of the VM you wish to clone from
  • clonename - Name of the cloned VM
  • vmfolder - Name of a vCenter folder
  • datastorecluster - Name of a datastore cluster

Here is a screenshot of cloning an existing VM onto a datastore cluster:

The script is pretty straight forward and it can easily be adapted to include other configurations as required in your own environment.

Hopefully this gives you a better idea on how to leverage the new provisioning APIs for Storage DRS and start automating your VM deployments onto datastore clusters and get the benefits Storage DRS in your vSphere environment.