In my previous blog post How to backup VMs in ESX onto Dropbox, I showed you how to backup your virtual machines on ESX to your Dropbox account, but who said it should stop there? I realized after playing with Dropbox on ESX, I had a crazy idea of trying to run a virtual machine that was stored in my Dropbox account. Since I am using the free Dropbox account, I have a maximum of 2GB of online storage and decided to spin up a tiny Linux virtual machine and upload it to my Dropbox account. Not surprised, I was able to register the virtual machine and fire it up and it worked like a charm.
Now, this got me thinking …. if I can run a virtual machine from Dropbox via ESX, could I get another ESX host to see this same Dropbox account? The answer is YES! One feature of Dropbox is the ability to access your files across multiple devices: Windows, Linux, Mac OSX desktop, iPhone, iPad, Andriod and of course ESX. For demonstration purposes, I created two virtual ESX 4.1 hosts called west and east and authorized both hosts to access my Dropbox account.
Here is a screenshot of the two ESX hosts via "My Computers" tab on Dropbox account:
Here is a screenshot of the small 1GB Linux Debian virtual machine I created and uploaded to my Dropbox account:
Here is a screenshot of both ESX hosts (east and west) accessing the directory of the small Linux virtual machine:
I registered the virtual machine on the west coast ESX host and here is a side by side screenshot of both vSphere Clients:
As you can see, the virtual machine is powered on and running. If we take a look at where the virtual machine configuration file and disks is stored, you will see it is currently on the Dropbox account accessed by "west" coast ESX host:
Here is a screenshot showing the registration of the small Linux VM on west and there is currently nothing registered on east:
Let's say we had a failure on the west coast ESX host and we need to access this virtual machine via east coast ESX host. I registered the virtual machine and powered it on and now the system is back up and running again:
Again, we can see the configuration and virtual disk is now being accessed from the Dropbox account by the east coast ESX host:
We also confirm that the virtual machine is now registered on the east coast ESX and there is nothing running on the west coast ESX host:
As you can see from this simple demonstration, you can easily run a virtual machine and have it accessible via multiple ESX host, though I would not recommend you go out and start putting your production VMs on Dropbox, but it is an interesting idea for cloud storage 😉
Note: While testing, I found the synchronization process between the two ESX host to be slightly off and were not always up to date when a change was made. I had to restart the Dropbox daemon several times after I created the virtual machine for the other ESX host to see the updated files. I am pretty sure it is an issue with the daemon versus dropbox, since I can see the files updated on the web browser immediately. I would be very careful to ensure that only one host is accessing the files, else you could see some discrepancies.