6.0.3

Table Of Contents
If you are using the vSphere Web Client and connecting to a browser-based virtual machine console, the
following access must be possible:
n
The rewall must allow vSphere Web Client to access vCenter Server on port 9443.
n
The rewall must allow vCenter Server to access the ESXi host on port 902.
Connecting to a Standalone Virtual Machine Console Through the
vSphere Web Client
If you are using the vSphere Web Client and connecting to a standalone virtual machine console, the
following access must be possible:
n
The rewall must allow vSphere Web Client to access vCenter Server on port 9443.
n
The rewall must allow the standalone virtual machine console to access vCenter Server on port 9443
and to access the ESXi host on port 902.
Connecting to ESXi Hosts Directly with the vSphere Client
You can use the vSphere Client virtual machine console if you connect directly to an ESXi host.
N Do not use the vSphere Client to connect directly to hosts that are managed by a vCenter Server
system. If you make changes to such hosts from the vSphere Client, instability in your environment results.
The rewall must allow access to the ESXi host on ports 443 and 902
The vSphere Client uses port 902 to provide a connection for guest operating system MKS activities on
virtual machines. It is through this port that users interact with the guest operating systems and applications
of the virtual machine. VMware does not support conguring a dierent port for this function.
Secure the Physical Switch
Secure the physical switch on each ESXi host to prevent aackers from gaining access to the host and its
virtual machines.
For best protection of your hosts, ensure that physical switch ports are congured with spanning tree
disabled and ensure that the non-negotiate option is congured for trunk links between external physical
switches and virtual switches in Virtual Switch Tagging (VST) mode.
Procedure
1 Log in to the physical switch and ensure that spanning tree protocol is disabled or that Port Fast is
congured for all physical switch ports that are connected to ESXi hosts.
2 For virtual machines that perform bridging or routing, check periodically that the rst upstream
physical switch port is congured with BPDU Guard and Port Fast disabled and with spanning tree
protocol enabled.
In vSphere 5.1 and later, to prevent the physical switch from potential Denial of Service (DoS) aacks,
you can turn on the guest BPDU lter on the ESXi hosts.
3 Log in to the physical switch and ensure that Dynamic Trunking Protocol (DTP) is not enabled on the
physical switch ports that are connected to the ESXi hosts.
4 Routinely check physical switch ports to ensure that they are properly congured as trunk ports if
connected to virtual switch VLAN trunking ports.
Chapter 8 Securing vSphere Networking
VMware, Inc. 231