Diskhotplug

diskhotplug is a command-line utility that you can use to manage IS Controller. 

Starting from the 6.0 version, OnApp Cloud supports diskhotplug for CloudBooted compute resources using the Integrated Storage platform. You can assign and unassign hardware disks from the IS Controllers on the compute resources, using the CLI utility.

To use the hotplug, run the following command from the required compute resource:

diskhotplug

You will see the list of all commands related to the diskhotplug utility.

To avoid warning messages such as DELAYED_PING showing at the Diagnostics page, it will also be necessary to forget the disk drive. Whenever removing a disk drive permanently from OnApp Integrated Storage forget should be used. This can be performed by selecting nodes, finding the corresponding node, and then using the Forget option.

List of Available diskhotplug Commands

• diskhotplug list - lists existing Controllers. Following is an example for a system with 6 disk drives set with default 4 drives per controller:

  > [root@x.x.x.x ~]# /diskhotplug list
  > Controller 0
  >       Slot 0 - /dev/sda (SCSIid:Z2A7VJQD_Z2A7VJQD,NodeID:130322041)
  >       Slot 1 - /dev/sdb (SCSIid:9WM6B5WQS_9WM6B5WQ,NodeID:4043912490)
  >       Slot 2 - /dev/sdc (SCSIid:9WM6B955S_9WM6B955,NodeID:2281894381)
  >       Slot 3 - /dev/sdd (SCSIid:CVPR116003YH160DGN_2CW16_CVPR116003YH160DGN,NodeID:476612602)
  > Controller 1
  >       Slot 0 - /dev/sde (SCSIid:350025388500786eb_S1D9NEAD904298P,NodeID:235613508)
  >       Slot 1 - /dev/sdf (SCSIid:35000cca0220b54c8_KPV675RF,NodeID:2574447922)
  >       Slot 2 - EMPTY
  >       Slot 3 - EMPTY

  CODE

• diskhotplug assign <Controller> <Slot> <device> - assigns disks to Controller

  diskhotplug assign 3 0 /dev/sdh
  result=SUCCESS

  CODE

• diskhotplug unassign <Controller> <Slot> - unassings disk from Controller. You can use the command when you face some mechanical disk failure or to move it to another server manually.

  In the example below, /dev/sdf is being removed:

  > [root@x.x.x.x ~]# /diskhotplug unassign 1 1
  Result of diskhotplug unassign:
  > [root@x.x.x.x ~]# /diskhotplug list
  > Controller 0
  >       Slot 0 - /dev/sda (SCSIid:Z2A7VJQD_Z2A7VJQD,NodeID:130322041)
  >       Slot 1 - /dev/sdb (SCSIid:9WM6B5WQS_9WM6B5WQ,NodeID:4043912490)
  >       Slot 2 - /dev/sdc (SCSIid:9WM6B955S_9WM6B955,NodeID:2281894381)
  >       Slot 3 - /dev/sdd (SCSIid:CVPR116003YH160DGN_2CW16_CVPR116003YH160DGN,NodeID:476612602)
  > Controller 1
  >       Slot 0 - /dev/sde (SCSIid:350025388500786eb_S1D9NEAD904298P,NodeID:235613508)
  >       Slot 1 - EMPTY
  >       Slot 2 - EMPTY
  >       Slot 3 - EMPTY

  CODE

• diskhotplug assign <Controller> <Slot> <device> - assigns disks to Controller

  > [root@x.x.x.x ~]# /diskhotplug assign 1 1 /dev/sdf
  > [root@x.x.x.x ~]# /diskhotplug list
  > Controller 0
  >       Slot 0 - /dev/sda (SCSIid:Z2A7VJQD_Z2A7VJQD,NodeID:130322041)
  >       Slot 1 - /dev/sdb (SCSIid:9WM6B5WQS_9WM6B5WQ,NodeID:4043912490)
  >       Slot 2 - /dev/sdc (SCSIid:9WM6B955S_9WM6B955,NodeID:2281894381)
  >       Slot 3 - /dev/sdd (SCSIid:CVPR116003YH160DGN_2CW16_CVPR116003YH160DGN,NodeID:476612602)
  > Controller 1
  >       Slot 0 - /dev/sde (SCSIid:350025388500786eb_S1D9NEAD904298P,NodeID:235613508)
  >       Slot 1 - /dev/sdf (SCSIid:35000cca0220b54c8_KPV675RF,NodeID:2574447922)
  >       Slot 2 - EMPTY
  >       Slot 3 - EMPTY

  CODE

• diskhotplug initNewController - creates a new one Controller

  diskhotplug initNewController
  Complete: added new controller: 4

  CODE

• diskhotplug restartController <Controller> - restarts existing Controller

  diskhotplug restartController 3
  Stopping Controller 3...DONE
  Re-initialising config...DONE
  Starting Controller 3...DONE

  CODE

NOTE:

• Use the UI diagnostic view to query the current state of the Integrated Storage platform.
• Check that all vDisk content is redundant and all vDisks are in sync before attempting to unassign a physical drive when it is still active in the system.
• If no free slots are available while assigning disks using hotplug, the system will automatically initialize new controllers to assign the required number of disks.