How to find RAID configuration/level and RPM speed having only remote access to the server?

Question

Having only remote access (no physical access), to a server (that is SSH), how do I (or may be is it possible):

1. find out whether it is RAID configured or not? If it is RAID configured, whether it is software or hardware RAID? What level of RAID it is?
2. find the RPM speed of the hard disk?

NOTE: In this case, I've access to both RHEL4/5 and CentOS4/5 based Linux servers.

EDIT

Here is an output of mount command from a RHEL4 server:

/dev/mapper/VolGroup00-LogVol00 on / type ext3 (rw)
none on /proc type proc (rw)
none on /sys type sysfs (rw)
none on /dev/pts type devpts (rw,gid=5,mode=620)
usbfs on /proc/bus/usb type usbfs (rw)
/dev/sda1 on /boot type ext3 (rw)
none on /dev/shm type tmpfs (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)

Solution 1

Software raid would probably show up in a df -h listing. Try to find references to /dev/md*. But you've mentioned vendor hardware, so I'll assume you're trying to get info on hardware RAID controllers.

Depending on the server hardware, I will try a few techniques to get system information. I start with dmidecode, usually piped into less to obtain the server make/model information (and potentially, the serial number). For HP systems, this helps narrow down to a particular model or part number. In that case, I can infer the raid controller info. For Dell, dmidecode | grep -i serial should output the service tag. You can cross reference the initial build info from Dell's support site.

HP setups are fairly easy. You can cat /proc/driver/cciss/cciss* and receive an output like:

cciss1: HP Smart Array P800 Controller
Board ID: 0x3223103c
Firmware Version: 4.12
IRQ: 122
Logical drives: 2
Current Q depth: 0
Current # commands on controller: 0
Max Q depth since init: 217
Max # commands on controller since init: 386
Max SG entries since init: 31
Sequential access devices: 0

cciss/c1d0:      587.12GB       RAID 1(1+0)
cciss/c1d1:     1000.17GB       RAID 1(1+0)

Obtaining the disk rotation speed info would require installing the HP Proliant Support Pack or at least the hpacucli utility to get the drive specifics.

For Dell and most other hardware raid controllers, cat /proc/scsi/scsi should reveal the SCSI controller and/or RAID controller config.

Attached devices:
Host: scsi0 Channel: 00 Id: 00 Lun: 00
  Vendor: TEAC     Model: DVD-ROM DV-28SW  Rev: R.2A
  Type:   CD-ROM                           ANSI  SCSI revision: 05
Host: scsi2 Channel: 00 Id: 00 Lun: 00
  Vendor: SEAGATE  Model: ST9146803SS      Rev: FS62
  Type:   Direct-Access                    ANSI  SCSI revision: 05
Host: scsi2 Channel: 00 Id: 01 Lun: 00
  Vendor: SEAGATE  Model: ST9146803SS      Rev: FS62
  Type:   Direct-Access                    ANSI  SCSI revision: 05
Host: scsi2 Channel: 01 Id: 00 Lun: 00
  Vendor: Dell     Model: VIRTUAL DISK     Rev: 1028
  Type:   Direct-Access                    ANSI  SCSI revision: 05

Armed with the drive model numbers, you can google to obtain the specifications. The last entry in the output clearly shows a virtual disk comprised of the two physical disks listed above. You can get the exact controller spec from lspci -v.

Solution 2

You have an LVM logical volume mounted here :

/dev/mapper/VolGroup00-LogVol00 on / type ext3 (rw)

See the output from lvdisplay, vgdisplay and pvdisplay to have details about the LVM setup. LVM volumes are generally simple aggregates (RAID-0), but they can be mirrored too (RAID-1).

I see that you have a Perc 6/i. These are based upon LSI Megaraid IIRC. You can use the MegaCli tool (dowloaded from lsi.com) to get the RAID hardware configuration :

MegaCli -LDPDInfo -aALL -NoLog

Comments

[ewwhite]

Do you know what type of server hardware the system is running? HP? Dell?

[Gnanam]

@ewwhite: In some cases of mine, we don't even know (or forget) about that because we manage more than one customer production server. But in this particular case, it is Dell.

[Lester Cheung]

@Gnanam dmidecode is your friend if you have no idea what hardware you are working on: linux.die.net/man/8/dmidecode

[Gnanam]

@silviud: FYI. Output of mount command is posted in this question. Can you suggest/comment on this?

[Gnanam]

@silviud: Output of hdparm -tT /dev/mapper/VolGroup00-LogVol00 command: /dev/mapper/VolGroup00-LogVol00: Timing cached reads: 3144 MB in 2.03 seconds = 1548.24 MB/sec Timing buffered disk reads: 114 MB in 4.24 seconds = 26.86 MB/sec

[silviud]

looks like you have software raid but now you need to see if is done only on a disk or two - you can issue lvm pvdisplay -- if you see more then one disk then you have software raid with two or more disks

[Gnanam]

@silviud: But you said, if the output is something like /dev/md then it should be software raid, but my output here doesn't contain/look similar to that, how do you confirm it as software RAID then? Can you clarify?

[Gnanam]

Here is my output of cat /proc/scsi/scsi: Attached devices: Host: scsi0 Channel: 00 Id: 32 Lun: 00 Vendor: DP Model: BACKPLANE Rev: 1.05 Type: Enclosure ANSI SCSI revision: 05 Host: scsi0 Channel: 02 Id: 00 Lun: 00 Vendor: DELL Model: PERC 6/i Rev: 1.21 Type: Direct-Access ANSI SCSI revision: 05 Host: scsi2 Channel: 00 Id: 00 Lun: 00 Vendor: HL-DT-ST Model: CDRW/DVD GCCH30N Rev: A101 Type: CD-ROM ANSI SCSI revision: 05

[ewwhite]

It's a Perc 6/i RAID controller. You can probably install Dell's management agents to get more info from this point.

[silviud]

real devices come into /dev/sda...z - logical devices that is to say you have an extra layer on top of the physical device will come into different forms - you can have /dev/md if you manage the disks with mdadm but you can manage as well with lvm (logical volumes) - your config from what i've seen looks like one physical device and lvm on top - this is default into linux installations if you don't change the disk schema.

[silviud]

also as mentioned you have a perc controller from dell - it could that this does already raid for you but at the hardware level - meaning you can not see much about it unless you install a tool for dell raid - see above. if that is true then you may have -- hardware raid and on top you have lvm (for lvm you need to run the command lvm pvdisplay to see how many drives are part of it)