I just had an issue with vCenter 6.0 and ESXi 6.0 where I was unable to deploy OVF power on a VM.

The error which I was faced with was a relatively generic message based on the host connection status.

"The operation is not allowed in the current connection state of the host"

After I decided to have VSAN on my small home lab, I looked up some best practices, and this is what I've come up with. 

1. The Host Syslog should not be on the VSAN Datastore 

Sometimes you need pass through Trunk to VMs on ESXi emvitonment. Ex: Nested ESXi with NSX.

To set a standard vSwitch portgroup to trunk mode:

1. Edit host networking via the Virtual infrastructure Client.
2. Navigate to Host > Configuration > Networking > vSwitch > Properties.
3. Click Ports > Portgroup > Edit.
4. Click the General tab.
5. Set the VLAN ID to 4095. A VLAN ID of 4095 represents all trunked VLANs.
6. Click OK.

To set a distributed vSwitch portgroup to trunk mode:

1. Edit host networking via the Virtual infrastructure Client.
2. Navigate to Home > Inventory > Networking.
3. Right-click on the dvPortGroup and select Edit Settings.
4. Within that dvPortGroup, go to Policies > VLAN.
5. Set VLAN type to VLAN Trunking and specify a range of VLANs or specificy a list of VLANs to be passed to the Virtual machines connected to this portgroup.
   Note: To improve security, virtual Distributed Switches allow you to specify a range or selection of VLANs to trunk rather than allowing all VLANS via VLAN 4095.

• Configure Single Sign On
• Specify a Syslog Server