The following reference material from the vSphere 6.5 online documentation will assist you in cover the main information that is need to know the section:
- Enable or Disable UEFI Secure Boot for a Virtual Machine
- UEFI Secure Boot for ESXi Hosts
- Incoming and Outgoing Firewall Ports for ESXi Hosts
- NFS Client Firewall Behavior
- Securing ESXi Host
- Assigning Privileges for ESXi Hosts
- Set the vCenter Server Password Policy
- Lockdown Mode
- Disable the Managed Object Browser
- ESXi Passwords and Account lockout
- Best Practices for vCenter Server Access Control
- Manage Certificates with the Platform Services Controller Web Interface
- Using the MOB to explore the Object Model
- Securing vCenter Server
- Preventing a Virtual Machine User or Process from Disconnecting Devices
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