source http://www.v-front.de/2014/09/vmware-releases-vsphere-55-update-2.html
How to update your free and/or standalone ESXi host
If you want to update your standalone ESXi host to 5.5 Update 2 then you can use the procedure that I already explained for earlier updates. For your convenience here are the commands for easy copy/paste:
Enable SSH access on your host, log in to it (e.g. using putty) and run the following commands:
view source
print?
2 | esxcli network firewall ruleset set -e true -r httpClient |