I have an HP Smart Array P400 RAID controller with six physical disks configured in RAID 5. Four of the physical disks are in "OK" state, one is in "Predictive Failure" state, and one is in "spare" state:

logicaldrive 1 (3.6 TB, RAID 5, OK)

physicaldrive 1I:1:1 (port 1I:box 1:bay 1, SATA, 1 TB, Predictive Failure)
physicaldrive 1I:1:2 (port 1I:box 1:bay 2, SATA, 1 TB, OK)
physicaldrive 1I:1:3 (port 1I:box 1:bay 3, SATA, 1 TB, OK)
physicaldrive 1I:1:4 (port 1I:box 1:bay 4, SATA, 1 TB, OK)
physicaldrive 1I:1:5 (port 1I:box 1:bay 5, SATA, 1 TB, OK)
physicaldrive 1I:1:6 (port 1I:box 1:bay 6, SATA, 1 TB, OK, spare)

Is it safe to add (hpacucli controller slot=6 array A add drives=1:6) a "spare" drive to RAID 5 and once its drive type changes from "Spare Drive" to "Data Drive", then remove (either physically or maybe with hpacucli controller slot=6 array A remove drives=1:1) the HDD with the "Predictive Failure" state?

2 Answers 2


Wait until the drive fails or physically remove or replace it.

Seeing "Predictive Failure" in an indication to order a new drive.

The best course of action if to get a new drive and replace the failing drive with it (and not to rely on the spare rebuild).

  • Thanks! So when I physically remove the HDD in Predictive Failure state, then the spare drive will change its Drive Type from Spare Drive to Data Drive? The reason I would like to get rid of this Predictive Failure HDD is that I have some file-system related issues on this server. Maybe they are not related(I don't know what exactly triggers this Predictive Failure in RAID controller), but I would like to exclude any possibilities.
    – Martin
    Commented Oct 13, 2017 at 10:40
  • @Martin Yes, the spare will rebuild automatically. But remember that the spare is subject to the same operating conditions (heat, vibration, wear) that the failing drive is. You should plan to replace the bad disk with another drive, at which point, the spare will go back to standby.
    – ewwhite
    Commented Oct 13, 2017 at 10:42

You may disable this predictive failure drive and this will initiate rebuilding with spare drive if you have it in configuration(you have):

hpacucli controller slot=6 physicaldrive 1I:1:1 modify disablepd

The second variant is to change drive spare activation mode:

hpacucli controller slot=6 modify spareactivationmode=predictive

But it is not supported for all controllers. The set-back command is

hpacucli controller slot=6 modify spareactivationmode=failure

Note, that you may need to use hpacucli or hpssacli or ssacli commands depending on the controller and operating system.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .