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How to clear the ARP cache on ESXi using new ESXCLI 5.5

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The ability to clear the ARP cache/table for an ESXi host is feature that has been requested from customers from time to time and usually for diagnosing network related issues. In previous releases, this was not something you could easily do and it was nice to see this feature get implemented in a new ESXCLI command that will be available as part of the vSphere 5.5 release.

The ESXCLI "network ip neighbor" namespace has been enhanced to include a new option:

You can list ARP table entries using the "list" operation and you can now clear a specific ARP entry using the "remove" operation.

To clear an ARP entry, you will need to specify the IP Address you wish to clear, the IP protocol whether it is IPv4 or IPv6 and you also have the option to specify the particular VMkernel interface. If you do not specify the particular VMKernel interface, then the entry will be removed for all interfaces.

Here is a screenshot of listing of the current ARP entries and then removing an entry for VMkernel interface 1:

This will definitely be a useful ESXCLI command to be aware of the next time you need to troubleshoot a network issue!

Note: I mentioned earlier that clearing the ARP cache was not something that you could do prior to vSphere 5.5. However, while working on this article, I actually learned it was possible to clear the ARP cache, but it was not very user friendly like the new ESXCLI 5.5 command. In a separate article, I will show you how can clear the ARP cache on earlier versions of ESXi.

If you wish to clear the ARP cache on an ESXi host prior to ESXi 5.5, please take a look at this article for more details.

VMware nested easter egg

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It is only fitting that if a VMware Engineer adds a hidden easter egg, that it would of course contain another nested easter egg! For those of you who are not familiar with the vPong easter egg, Raphael Schitz wrote an article about a year ago regarding this little nugget which is when I first learned about this as well.

The easter egg allows you to play a game of old school pong using either VMware Fusion, Workstation, Player and it even works on vSphere. To enable this easter egg, you just need to mount a 0 byte floppy image located on your desktop (not a datastore) to a virtual machine and power it up.

Here is a screenshot of mounting a dummy floppy image which I created using the "touch" command on my Mac OS X system and connecting it to a Fusion VM:

Once you power on the VM, you should now see a game of vPong in the VM console which you can then play against the computer using your mouse.

One would think the easter egg stops there, but nope, there is actually more. If you click into the VM console and type the word "pride" (all lower case), you will see that the black/white vPong game will now change to color! To disable the color, you just need to type the word "pride" again and it will go back to black/white.

I thought this was actually pretty cool and thanks to Regis Duchesne for sharing this tidbit! So the next time you are bored, you can always kill some time with the classic black/white pong or go for the more colorful version 🙂

VM Storage Policy APIs aka Storage Profile APIs will be available in vSphere 5.5

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A frequently requested feature from customers and partners have been around the Storage Profile APIs and with the upcoming vSphere 5.5 release, it will now be possible to automate the management and consumption of Storage Profiles. In vSphere 5.5, Storage Profiles has been renamed to VM Storage Policy and they have been enhanced from the previous version of Storage Profile. VM Storage Policy introduces new concept of a rule set also known as a sub-profile or sub-policy from an API perspective.

A VM Storage Policy can contain multiple rule sets which describes a requirement for a virtual machine storage resource. Each rule can either be an underlying storage capability or a user defined vSphere Tag.

One important thing to note about the VM Storage Policy API (SOAP API), is that it is exposed as a separate API endpoint (similar to how the SMS API is exposed) on vCenter Server and it will not be accessible through the normal vSphere API. To consume this API, you will need to connect to the PBM (Policy Based Management) Server which requires an authenticated vCenter Server session. A great way to learn and explore the new SPBM API is to check out the SPBM MOB.

Here is the high level workflow for connecting to the PBM Server:

  1. Login to vCenter Server
  2. Extract the session cookie
  3. Add vCenter Server session cookie & connect to PBM Server

Once connected to the PBM Server, you will have access to PBM ServiceInstance with following three managed objects:

    • ProfileProfileManager (not a typo, repeat of Profile for some reason)
    • PlacementSolver
    • ComplianceManager

As mentioned earlier, a VM Storage Policy can be made up of several rule sets and each rule set contains a property rule. Here is the specification for what the VM Storage Policy looks like from an API perspective:

For managing and creating VM Storage Policies, you will need use the new VM Storage Policy API and for consuming and assigning VM Storage Policies to a virtual machine, you will need to use the vSphere API. When provisioning or cloning a virtual machine, there is a new profile property that denotes the MoRef ID for a particular VM Storage Policy.

As part of the VM Storage Policy API, there will be a Java SDK that includes a programming guide that goes over the VM Storage Policy API in greater detail as well as several sample programs exercising the various API methods. Since the VM Storage Policy API is a SOAP API similar to the vSphere API, the WSDL will also be available if you wish to generate your own language binding to the API.

Here is a screenshot of the available sample programs leveraging the new VM Storage Policy API:

Here is an example of one of the sample programs which lists all the VM Storage Policies for a given vCenter Server:

run.bat ListProfiles --vcurl https://[VC-IP]/sdk/vimService --ssourl https://[VC-IP]:7444/ims/STSService --spbmurl https://[VC-IP]/pbm --username *protected email* --password vmware --ignorecert

In the screenshot, you will see four VM Storage Policy being shown, one which I had created earlier and there others which are VM Storage Policies created by VSAN. You will notice that you will need three pieces of information when connecting: vCenter Server endpoint, SSO Server endpoint and PBM Server endpoint. You can find more details by referring to the VM Storage Policy Programming Guide and VM Storage Policy API reference.