Minimum physical drives not reached

[KonstantinT]

Hi there,

Could you please assist



Our HP server has multiple array configuration, for example:


=> ctrl all show config

Smart Array P420i in Slot 0 (Embedded)    (sn: xxxxxxxxxxxxxxxxxx)

   array A (Solid State SATA, Unused Space: 0  MB)


      logicaldrive 1 (223.5 GB, RAID 1, OK)

      physicaldrive 1I:1:1 (port 1I:box 1:bay 1, Solid State SATA, 240.0 GB, OK)
      physicaldrive 1I:1:2 (port 1I:box 1:bay 2, Solid State SATA, 240.0 GB, OK)

   array B (SATA, Unused Space: 0  MB)


      logicaldrive 2 (10.9 TB, RAID 1+0, OK)

      physicaldrive 1I:1:3 (port 1I:box 1:bay 3, SATA, 4000.7 GB, OK)
      physicaldrive 1I:1:4 (port 1I:box 1:bay 4, SATA, 4000.7 GB, OK)
      physicaldrive 1I:1:7 (port 1I:box 1:bay 7, SATA, 8001.5 GB, OK)
      physicaldrive 1I:1:8 (port 1I:box 1:bay 8, SATA, 8001.5 GB, OK)
      physicaldrive 1I:1:9 (port 1I:box 1:bay 9, SATA, 8001.5 GB, OK)
      physicaldrive 1I:1:10 (port 1I:box 1:bay 10, SATA, 8001.5 GB, OK)

   array C (SATA, Unused Space: 0  MB)


      logicaldrive 3 (7.3 TB, RAID 0, OK)

      physicaldrive 1I:1:5 (port 1I:box 1:bay 5, SATA, 4000.7 GB, OK)
      physicaldrive 1I:1:6 (port 1I:box 1:bay 6, SATA, 4000.7 GB, OK)

   Enclosure SEP (Vendor ID HP, Model Gen8 ServBP 12+2) 378 (WWID: xxxxxxxxxxxxxxxxx, Port: 1I, Box: 1)

   Expander 380 (WWID: xxxxxxxxxxxxxxxxxxx, Port: 1I, Box: 1)

   SEP (Vendor ID PMCSIERA, Model SRCv8x6G) 379 (WWID: xxxxxxxxxxxxxxxxxxx)

=>


array A - RAID 1
array B - RAID 10
array C - RAID 0


These arrays are ok, but currently we need to move two physical drives (1I:1:3 and 1I:1:4 which are 4Gb) from the logicaldrive 2 (array B) to logicaldrive 3 (array C)

How can we do this, without physical remove them from the array ?

As an example, we can't do this via utility hpacucli, because of these errors : 

=> controller slot=0 array B remove drives=1I:1:3-1I:1:4

Error: This operation is not supported with the current configuration. Use the
"show" command on devices to show additional details about the
configuration.
Reason: Minimum physical drives not reached

=>

and

=> controller slot=0 array B modify drives=1I:1:3-1I:1:4

Error: This operation is not supported with the current configuration. Use the
"show" command on devices to show additional details about the
configuration.
Reason: Minimum physical drives not reached

=>

[Fritsch James]

I think you cannot do this. You will have to delete array B and array C and create them new in your desired configuration. If you want to do it without data loss you need to create backups and restore those to the newly created raidset.

(If you have BBWC/FBWC enabled you can add drives to an array and expand it, but you cannot remove drives from an array without degrading it)

[KonstantinT]

Hi Fritsch James,

Thanks for replying

I know that RAID 10 configuration requires a minimum of four disks. In my RAID configuration I have six drives, but what heppend if I try to physicaly remove two disks from there.

Does RAID automatically rebuild configuration without data losing with four disks ?

[Torsten.]

According to SSA user guide this is possible:

Removing a drive from an array (restripe the data on an array to occupy fewer physical
drives, then remove the excess drives from the array)

if there is enough free space available.

Some controllers may not support this option or may require a license key to enable this feature.

But:

After the shrink, the array must have sufficient capacity to contain all of the configured logical volumes.

IMHO you need free space not occupied by logical drives for this shrink operation.

[KonstantinT]

More info about RAID:

=> ctrl slot=0 ld 2 show

Smart Array P420i in Slot 0 (Embedded)

array B

Logical Drive: 2
Size: 10.9 TB
Fault Tolerance: 1+0
Heads: 255
Sectors Per Track: 32
Cylinders: 65535
Strip Size: 256 KB
Full Stripe Size: 768 KB
Status: OK
Caching: Enabled
Unique Identifier: xxxxxxxxxxxxxxxxxxxxxxxx
Disk Name: /dev/sdb
Mount Points: None
Logical Drive Label: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Mirror Group 0:
physicaldrive 1I:1:3 (port 1I:box 1:bay 3, SATA, 4000.7 GB, OK)
physicaldrive 1I:1:4 (port 1I:box 1:bay 4, SATA, 4000.7 GB, OK)
physicaldrive 1I:1:7 (port 1I:box 1:bay 7, SATA, 8001.5 GB, OK)
Mirror Group 1:
physicaldrive 1I:1:8 (port 1I:box 1:bay 8, SATA, 8001.5 GB, OK)
physicaldrive 1I:1:9 (port 1I:box 1:bay 9, SATA, 8001.5 GB, OK)
physicaldrive 1I:1:10 (port 1I:box 1:bay 10, SATA, 8001.5 GB, OK)
Drive Type: Data
Caching Association: None

=>

Important to know does RAID automatically rebuild configuration without data losing ?

Because we need to remove two disks:

physicaldrive 1I:1:3 (port 1I:box 1:bay 3, SATA, 4000.7 GB, OK)
physicaldrive 1I:1:4 (port 1I:box 1:bay 4, SATA, 4000.7 GB, OK)

[Torsten.]

I never did this, but you probably need to remove 1 drive from each group:

1I:1:3 and 1I:1:8

If this works, you can "replace" the remaining 4TB disk with the removed 8TB disk.

But the problem might be this:

The 4TB disk is setting the limit, so you have 2 groups of 3x 4TB disks in use = 12 TB, but the logical drive is 10TB, hense there is  not enough space to remove a disk, because you need 3x 4TB disks to reach 10TB.

Maybe you can convert the RAID1+0 to a RAID0 first, remove disks, then convert to RAID1+0 again.

[KonstantinT]

Hi Torsten

Thanks for reply

I know that HP Smart Array controllers split the disks as such:

physicaldrive 1I:1:3 pairs to physicaldrive 1I:1:8
physicaldrive 1I:1:4 pairs to physicaldrive 2I:1:9
physicaldrive 1I:1:7 pairs to physicaldrive 2I:1:10

And if I remove 1 drive from each group:

1I:1:3 and 1I:1:8

I will lose all my data, 

Or I am wrong ?

[Torsten.]

the goal is this - the system re- organize the data, free the disk and tell you ready to remove.

but there is not enough free space ...