I have a HP ProLiant DL360 Gen9 server which has three physical 900GB HDDs. Those three HDDs are in some sort of hardware RAID setup. RAID controller is HP 3239 and it uses hpsa driver. For OS it represents itself as a 900GB sda
device. Now if I check the RAID level with # cat /sys/class/scsi_disk/0:0:0:1/device/raid_level
, then it shows RAID 1(1+0)
. Is this some sort of RAID 10 with three physical drives? Or is it triple mirroring? What is also interesting is that while activity LEDs of two drives blink in sync, then the third drive shows very little activity. Last but not least, I am not able to install additional software on this server because it is Linux based special appliance.
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1What type of "special appliance" is it?– ewwhiteCommented Mar 30, 2016 at 14:04
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It is an AlienVault OSSIM.– MartinCommented Mar 30, 2016 at 19:01
3 Answers
HP DO do a form of R1 where it writes to three disks instead of 2 but it's rarely used, more likely the third disk is set aside as a hot-spare - or it's not being used at all!
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Looks like that third HDD is a dedicated spare drive Does this mean that when one of the drives in RAID1 fails, then this spare drive will automatically take its place?– MartinCommented Mar 30, 2016 at 19:50
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It looks like raid 1 with a hot spare. The HP array tools should be available for Linux from the HP website, depending on distro.
See if the system has the hpssacli
command installed.
If so, you can run
hpssacli ctrl all show config
to get the configuration of the array.If this command is not installed, you may want to install it... depending on the specific operating system being used.
You can also reboot and view the array configuration from the BIOS utility or by launching the
F10
Intelligent Provisioning menu.If you have access to the server's ILO4 interface, you can get the array configuration from that by clicking on the "Storage" menu.
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Thanks! As I did not want to install additional packages to this appliance, I finally reloaded the server and looks like this is a dedicated spare drive. I guess
RAID 1(1+0)
in output ofcat /sys/class/scsi_disk/0:0:0:1/device/raid_level
means that?– MartinCommented Mar 30, 2016 at 19:55 -
1No, it does not mean that. It means RAID 1 (or 1+0). The spare is not visible to the OS.– ewwhiteCommented Mar 30, 2016 at 20:31
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Ok, I see. The spare is visible only to RAID controller which automatically uses this drive if one of the RAID 1 mirror drives fails?– MartinCommented Mar 30, 2016 at 22:49
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