VMware Certified Professional - Data Center Virtualization (VCP-DCV) Practice Exam

When an administrator can manage an ESXi host through vCenter Server but cannot establish a direct connection to it, the likely cause is that Lockdown Mode is enabled on the ESXi host. Lockdown Mode restricts access to the host by disallowing direct connections via the vSphere client, SSH, or other management tools, thus requiring management solely through vCenter Server.

By disabling Lockdown Mode via vCenter Server, the administrator can regain direct access to the ESXi host. This is essential for tasks that need to be performed directly on the host, such as troubleshooting, configuration changes, or updates that may not be manageable through vCenter.

Restarting the management agents may help in scenarios where the management interfaces are unresponsive but does not necessarily address Lockdown Mode. Disabling the ESXi firewall could pose security risks and is not the primary solution since it could leave the host vulnerable. Rebooting the ESXi host should be a last resort as it entails downtime and does not guarantee resolution of the connectivity issue related to Lockdown Mode.