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Extending RVC to support renaming VM Storage Policies

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I was recently using RVC (Ruby vSphere Console) to setup one of my VSAN lab environments and I had noticed that in the SPBM namespace, that you could create and delete a VM Storage Policy, but you could not rename an existing one. The great thing about RVC is that it is very extensible and I thought it would be useful to have a spbm.profile_rename command, so I decided to build it!

The management of VM Storage Policies is performed through the SPBM API and there is a method called PbmUpdate() which allows you to rename an existing VM Storage Policy. In my environment, I exclusively use the VCSA (vCenter Server Appliance) and in the /root directory, you should see a .rvc directory. To extend the SPBM namepace, you just need to create a new file called spbm.rb which should contain the following snippet of code:

opts :profile_rename do
  summary "Rename a VM Storage Profile"
  arg :profile, nil, :lookup => RbVmomi::PBM::PbmCapabilityProfile
  arg :name, "New name", :type => :string
end

def profile_rename profile, name
  _catch_spbm_resets(nil) do
    pbm = profile.instance_variable_get(:@connection)
    pm = pbm.serviceContent.profileManager
    spec = PBM::PbmCapabilityProfileUpdateSpec(
      :name => name,
    )
    pm.PbmUpdate(:profileId => profile.profileId, :updateSpec => spec)
  end
end

Once you have saved the file, you can now connect to RVC and you should see a new command called spbm.profile_rename which takes an existing VM Storage Policy and the new name of the policy.

Here is an example of what that would look like where I have a VM Storage Policy called "Platinum" and I want to rename it to "Adamantium":

spbm.profile_rename localhost/Datacenter/storage/vmprofiles/Platinum/ Adamantium

SPBM (Storage Policy Based Management) MOB in vSphere 5.5

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A handy little tool that was useful for me which might come in handy for others too while working on my VSAN VM Storage Policy recovery article is the SPBM (Storage Policy Based Management) MOB which works similar to the vSphere MOB and FDM MOB for those of you who have used this interface before. The MOB stands for Managed Object Browser and simply put is an interface that allows you to browse the objects and properties of your vSphere environment by just using a web browser. You can also interact with the MOB by executing the same set of vSphere API methods as you would if you were to write a script or application which is useful for quickly getting a sense of what a certain property might look like or the output of an API method without writing a single line of code.

In vSphere 5.5, there is now an SPBM API which is available as a separate API endpoint on the vCenter Server. This new API allows you to manage the full lifecycle of a VM Storage Policy formally known as VM Storage Profiles from a programmatic standpoint which is very important when working with VSAN as everything is policy driven. For more more details about the new SPBM API, please take a look here. As mentioned earlier, one great way to learn about the API is by exploring the MOB and luckily the SPBM API includes one!

To access the SPBM MOB in vSphere 5.5, you will need to point your browser to your vCenter Server as that is where the endpoint is exposed using the following URL format:

http://[VC-IP-OR-HOSTNAME]:8190/mob

To access the SPBM MOB in vSphere 6.0, you will need to point your browser to your vCenter Server as that is where the endpoint is exposed using the following URL format:

http://[VC-IP-OR-HOSTNAME]/pbm/mob

You will be prompted for your vCenter Server credentials before the MOB will allow you to login. Once you are logged in you will be brought to the main service content of the SPBM endpoint similar to the vCenter Server service content and you can then click on content link to explore the various sub-managers that are available.
Note: You will be able to get more details on each of these sub-managers by taking a look at the VM Storage Policy Programming Guide and VM Storage Policy API reference guide.
To quickly show you around, I will provide a couple of examples using the ProfileManager and I am sure you can probably guess what type of functionality it provides :). The first method that we will take a look at is the PbmQueryProfile which will return the list of available VM Storage Policies that have been defined. You will need to set the resourceType property to "STORAGE" and remove the profileCategory and then click on "Invoke Method".
If you are using VSAN and you do not have any VM Storage Policies defined, there will still be two default VM Storage Policies that is automatically created when VSAN is enabled. What you will see are the internal identifiers for each of the VM Storage Policy and as you can see from the output I have 5 VM Storage Policies.
You will notice that the output does not contain the human readable display name for each VM Storage Policy, to retrieve that information we will need to use the PbmRetrieveContent which accepts a list of VM Storage Profile ID's and in return provide the human readable name as well as other properties such as the initial creation date and last modified date. Using the pre-canned input form, you can specify one or more VM Storage Profile IDs from the previous step and then click on "Invoke Method".
In my example, I specified two of my VM Storage Policies and I can see they map to the names  "Aluminum" and "Copper" which is what I named them when I first created the policies.
From here on out, we will be using the VM Storage Policy ID as that is what is used to uniquely identify a VM Storage Policy and input for majority of the SPBM API methods. Now if we want to see what objects (VM Home directory or VMDKs) are associated with a particular VM Storage Policy we can use the PbmQueryAssociatedEntity method. You will need to provide the VM Storage Policy ID and remove the entityType and then click on the "Invoke Method".
As you can see from the output this a virtualMachine object type which tells us this VM Storage Policy is used for the VM Home. Lets go ahead and specify a VM Storage Policy that is used for a Virtual Machine's VMDK and see what that looks like.
We now see the object type is virtualDiskId and you can see the particular VMDK and the associated Virtual Machine by looking at the key which has the format of vm-mo-ref:vmdk-key. Now what if we wanted to perform the reverse look up, by providing only a Virtual Machine or VMDK as input? Well, we can easily do this lookup by using the PbmQueryAssociatedProfiles method. This API method requires you to specify three parameters: objectType, key and serverUuid (technically speaking the serverUuid can be left out).
From the above examples you will get an idea of what the expected input format is for either a Virtual Machine or VMDK query.
Here is an example of a Virtual Machine query:
Here is an example of a VMDK query:
Hopefully this quick introduction of the SPBM MOB will give you a good idea on how you can leverage this interface, especially if you plan on using the new SPBM API to automate and manage your VM Storage Policies.

Restoring VSAN VM Storage Policy without vCenter Part 2: Using vSphere API

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Last week I demonstrated a manual method of recovering a VSAN VM Storage Policy when vCenter Server is no longer available by using a VSAN command-line utility found in the ESXi Shell called cmmds-tool. Though this approach works, it can also be quite tedious and error prone as you have to manually go through various configuration files and extract out the individual VSAN Object UUIDs. Luckily, one can automate the process outlined in the previous article by leveraging the vSphere API to connect directly to an ESXi host and access the VSAN Internal CMMDS system (Clustering Monitoring, Membership and Directory Services).

Disclaimer: This script is provided as a sample, please ensure it is properly tested before using it in a production environment.

I have created a sample vSphere SDK for Perl script called queryVSANVMStoragePolicyMapping.pl to demonstrate the vSphere API functionality. To use this script, you will need to ensure you have either the vCLI or vSphere SDK for Perl 5.5 installed on a system or you can use the vMA 5.5 appliance. You will also need to install an additional Perl module called JSON which is used in the script.

In my environment, I have a Virtual Machine called VSAN-VM-1 which has the following VM Storage Policies assigned to it.

Lets say our vCenter Server is now gone, how do we go about recovering the VM Storage Policy configurations to rebuild it on our new vCenter Server? With this script it is quite simple to recover the information by simply connecting to the ESXi host and specifying the name of the Virtual Machine.

Here is a sample execution of the script for my VSAN-VM-1:

From the output we can see that it automatically identifies the VSAN Object UUID for the VM Home directory as well as all VMDKs that are associated with that Virtual Machine. The script then uses that information to pass to the QueryCmmds API method which is part of the vsanInternalSystem manager to perform the query. The output is then returned as a JSON string which is parsed by the script to display the VM Storage Policy MoRef ID for each corresponding Virtual Machine component along with their configured VSAN policies.

The VM Home directory maps to our "Copper" policy which looks like the following in the vSphere Web Client:

The first VMDK maps to our "Platinum" policy which looks like the following in the vSphere Web Client:

The final VMDK maps to our "Aluminum" policy which looks like the following in the vSphere Web Client: