Typically, all ESXi hosts in a cluster have the same set of I/O filters installed. Occasionally, failures might happen during installation.

If an I/O filter installation fails on a host, the system generates events that report the failure. In addition, an alarm on the host shows the reason for the failure. Examples of failures include the following:

The VIB URL is not accessible from the host.

The VIB has an invalid format.

The VIB requires the host to be in maintenance mode for an upgrade or uninstallation.

The VIB requires the host to reboot after the installation or uninstallation.

Attempts to put the host in maintenance mode fail because the virtual machine cannot be evacuated from the host.

The VIB requires manual installation or uninstallation.

vCenter Server can resolve some failures. You might have to intervene for other failures. For example, you might need to edit the VIB URL, manually evacuate or power off virtual machines, or manually install or uninstall VIBs.