Connecting or Disconnecting a SCSI Controller

Use one of the following commands depending on the operation you want to perform.

• cfgadm -c connect controller – connects a controller.

• cfgadm -c disconnect controller – disconnects a controller.

Disconnecting the controller suspends all I/O activity on the SCSI bus until the cfgadm -c connect command is issued. The DR software initiated by the command to disconnect performs some basic checking to prevent critical partitions from being disconnected. However, the software cannot detect all cases. Some controllers on the system might be for disks that contain critical components of the root file system. Disconnecting these controllers would cause the system to hang and would require a system boot.

Thus, as a precaution during disconnect operations, a confirmation prompt always appears after you issue the command to disconnect. The command is executed only after you provide the confirmation.

The following example disconnects the SCSI controller c2 and also shows the confirmation prompt that follows the command.

# cfgadm -c disconnect c2
WARNING: Disconnecting critical partitions may cause system hang.
Continue (yes/no)?

The following example shows the state of the c2 controller after it has been disconnected. In the displayed information, the Receptacle field indicates the controller's new state. Further, the devices that are attached to it are also disconnected.

# cfgadm -al
Ap_Id           Type         Receptacle   Occupant     Condition
c2              unavailable  disconnected configured   unknownThe controller is disconnected.
c2::dsk/c2t0d0  unavailable  disconnected configured   unknownAttached device is disconnected.
c3              scsi-sas     connected    configured   unknown
c3::dsk/c3t0d0  disk         connected    configured   unknown
c3::dsk/c3t1d0  disk         connected    configured   unknown
c3::dsk/c3t2d0  disk         connected    configured   unknown
c3::dsk/c3t3d0  disk         connected    configured   unknown