So after a much to long time, I decided to arm myself against Intel’s microcode bug.

I was going to update my ESXi instance, running from an USB-stick, to the latest version, ESXi-6.5.0-20180104001-standard (Build 7526125).
After finding out that all ESXi updates do not have to be installed incremental I realized i only had to install the latest version of the hypervisor via the following instructions

 # Cut and paste these commands into an ESXi shell to update your host with this Imageprofile
 # See the Help page for more instructions
 #
 esxcli network firewall ruleset set -e true -r httpClient
 esxcli software profile update -p ESXi-6.5.0-20180104001-standard \
 -d https://hostupdate.vmware.com/software/VUM/PRODUCTION/main/vmw-depot-index.xml
 esxcli network firewall ruleset set -e false -r httpClient
 #
 # Reboot to complete the upgrade
 reboot -f

Found here

Trying to update the system I ran into the following error.

[InstallationError]

[Error 28] No space left on device

To fix this, in the web GUI go to Manage > System > Swap and enable swap on the datastore.