Oracle Solaris 10 9/10: In this Solaris release, the hotplug command is available to manage hot pluggible connections on PCI Express (PCIe) and PCI SHPC (Standard Hot Plug Controller) devices. This feature is not supported on other bus types, such as USB and SCSI.
You would still use the cfgadm to manage hot pluggible USB and SCSI devices as in previous Solaris releases. The benefit of using the hotplug features in this release is that in addition to enable and disable operations, the hotplug command provides offline and online capabilities for your supported PCI devices.
For more information, see PCIe Hot-Plugging With the (hotplug) Command.