Installing and Tweaking ESXi for VMware Fusion

This article is part of my Virtual Lab Series.

NOTE: If you want to enable VMware HA on your cluster, you might want to read this article first.  I *THINK* I had to bump up the memory to 2.5GB and the disk to 10GB.  Your results may vary!

Now that the SSD is installed in my laptop, it's time to throw some virtual machines at it!  I'm going to start by installing and tweaking ESXi in preparation for creating linked clones of this template to run my virtual vSphere Cluster.  If you've installed ESXi in a virtual machine before, skip ahead to the memory tweaks section; it has changed a bit with ESXi 4.1 as you'll see below.

Start by creating the virtual machine in Fusion and choosing VMware ESX as the OS:

Before clicking Finish, click Customize Settings:

Change the size of the Hard Disk from the default of 40GB to 5GB:

The rest of the install is a standard ESXi install.  The only issue I had was some keyboard "funkiness".  Some Function keys required me to hold down the Command key in addition (F11 was Command-F11 for instance).  I haven't assigned a machine name or static IP address yet because I'm going to create Linked Clones in Fusion so I will personalize the installs after the split.  After install, ESXi only consumed about 2.4 GB of disk space on the SSD.

The last step is to tweak the memory consumption of ESXi.  As stated in Duncan's original article and my previous post on setting this up in VMware Player, you can "trick" ESXi into using less than 2GB of memory by removing the memory check.  We have to perform a few additional steps is ESXi 4.1 because Tech Support Mode is disabled by default as shown below (Alt-F1 to see this and Alt-F2 to flip back to the ESXi screen)

Enable Local Tech Support Mode under the Troubleshooting Options menu:

With Local Tech Support enabled, we can now log in to the console on the ESXi virtual machine (remember Alt-F1 to flip to the Tech Support screen).  Log in as root:

As per Duncan's article, edit the /etc/vmware/esx.conf and add the line:

/vmkernel/minMemoryCheck = “false”

Once the entry is in place, shut down the server and set the memory to 1700 MB.  In ESXi 4.0 we could set it as low as 1200 MB but ESXi 4.1 seems to require a bit more.  What happens when you set the memory too low you ask?  The server will PSOD on boot like this:

Once all of this is complete, you should have a bootable ESXi virtual macine in a minimal footprint (less than 3GB of SSD and 1.7 GB of memory) and this will serve as a nice base configuration for our linked clones in the next article.