This article provides information about the Firewall feature introduced in VMware vSphere ESXi 5.0 and later, which provides a new access control capability for ESXi. These are important points about the ESXi 5.x firewall: ESXi 5.0 has a new firewall engine that is not based on iptables. The firewall is enabled by default and allows Internet Control Message Protocol (ICMP) pings and communication