When you are buying a cheap server from DC for your pet projects, those are commonly old HP servers - may have the option to preload with Vmware ESXI 6.0 . Now in present scenrio after so many attacks on vmware hosts it is not really recommended to use Vmware 6.0 anymore and you should upgrade as fast as possible.
To do that, download HP custom VMware image Offline bundle from following page to datastore
https://customerconnect.vmware.com/downloads/details?downloadGroup=OEM-ESXI65-HPE&productId=614
Then,
Check the version and name for the package using
esxcli software sources profile list -d /vmfs/volumes/datastore/Vmware.zip
which will show result like following
Name Vendor Acceptance Level
---------------------------------- -------------------------- ----------------
HPE-Custom-AddOn_700.0.0.10.5.5-46 Hewlett Packard Enterprise PartnerSupported
Now execute following command using the name as profile name
esxcli software profile update -d /vmfs/volumes/datastore/Vmware.zip -p HPE-Custom-AddOn_700.0.0.10.5.5-46
And you are done with upgrading. Please remember, I used profile name just an example. Exact version may not work. Just wanted to provide a quick and easy method rather going to through pain of using ISO or other methods.