The VMware-hostd service is the main interface between the ESXi host and VMkernel. It is required for most of the management tasks, including connections from vCenter, the VIC client directly, or remote command-line connections with esxcli or PowerCLI.

If the hostd service fails, the ESXi host becomes unmanageable. Fortunately, ESXi is still aware of all the running VMs, datastores, and so on, so the hostd failure does not affect virtual infrastructure availability. At the same time, most of the management operations are performed through vCenter, and the ability to power VMs on and off, vMotion, and so on, is vital for the administrator.

For rare cases, when the hostd service does not respond and cannot be restarted with standard means, vSphere 5 offers a new utility called localcli.

This tool works similar to esxcli but does not go through hostd, which makes it ideal to make changes in emergency situations. Any changes made with the tool will...