Trying to cluster a MSA2012 (2312 SAS) on RHEL5.3

[Brendan McDonald]

Hi, I'm trying to cluster a MSA 2012 (in reality it's a MSA2312 SAS) with 2 DL380's running RHEL 5.3.

I've downloaded and configured "hpacucli" drivers. I've then partitioned my disks ("fdisk /dev/sda" and the partition name is /dev/sda1).

The question I have for you is how do I now mount the disks ??? I've tried use "mount /dev/sda1" - doesn't work. I've tried "mount /dev/cciss/c0d1p1" and I get "mount: special device /dev/cciss/c1d0p1 does not exist"

Here's the relevant entry from dmesg.

scsi0 : ioc0: LSISAS1068E B3, FwRev=01192100h, Ports=1, MaxQ=343, IRQ=122
mptsas: ioc0: attaching ssp device: fw_channel 0, fw_id 1, phy 0, sas_addr 0x500
c0ffda2224400
target0:0:0: add device: fw_channel 0, fw_id 1, phy 0, sas_addr 0x500c0ffda2224
400
Vendor: HP Model: MSA2312sa Rev: M110
Type: Enclosure ANSI SCSI revision: 05
Vendor: HP Model: MSA2312sa Rev: M110
Type: Direct-Access ANSI SCSI revision: 05
SCSI device sda: 2148437472 512-byte hdwr sectors (1100000 MB)
sda: Write Protect is off
sda: Mode Sense: 93 00 00 08
SCSI device sda: drive cache: write back
SCSI device sda: 2148437472 512-byte hdwr sectors (1100000 MB)
sda: Write Protect is off
sda: Mode Sense: 93 00 00 08
SCSI device sda: drive cache: write back
sda: unknown partition table
sd 0:0:0:1: Attached scsi disk sda


I'd love some ideas on where to go.

Thanks

[Matti_Kurkela]

Apparently you've plugged your disk MSA into a generic SCSI interface, not into the SmartArray controller. This is what causes your disks to be visible as /dev/sd* instead of /dev/cciss/*.
I guess this might perhaps be a requirement of your cluster configuration?

A simple "mount /dev/sda1" works only if two conditions are met:

- the disk already has a filesystem that is in a valid state, and

- there is a line in /etc/fstab that tells the mount command where this device is supposed to be mounted.

After partitioning the disks, you must first create a filesystem on the partition(s). In Windows, this is called "formatting the partition". For example, to use the ext3 filesystem type:

mkfs.ext3 /dev/sda1

The next step is the creation of the mount point. It's simply an empty directory which will be used as an attachment point for the new filesystem. For example, if you want to mount the new filesystem to /someplace:

mkdir /someplace

If you're building a cluster, look at the instructions of the cluster system of your choice: typically you must not add cluster filesystems to /etc/fstab, but into some cluster configuration file instead. When the cluster is in operation, it will evaluate the state of the entire cluster before mounting the cluster filesystems.

To manually mount your filesystem when /etc/fstab has no information about it, you must specify both the device and the mountpoint you wish to use:

mount /dev/sda1 /someplace

Unmounting has no such requirement: both

umount /dev/sda1

and

umount /someplace

will work just the same.

MK

[Brendan McDonald]

Hi MK, thanks for you response.

I have a HP SC08Ge Host Bus Adapter which is attached to my Hp DL380 server.

The mkfs.ext3 command works and I can mount the disk.

What I was thinking I need to do now is use mdadm. If I use "mdadm --create --level multipath -n 2 /dev/md0 /dev/??? /dev/???"

I know the /dev/??? needs to be the 2 paths to my attached storage. How can I find what these 2 paths are???

[Brendan McDonald]

Found the problem.

Looking at "fdisk /dev/sda" and the partition is "/dev/sda1". I then checked /dev/sdb and found the same disk.

At this point I could use "mdadm --create --level multipath -n 2 /dev/md0 /dev/sda1 /dev/sdb1"

I then rechecked all my connections and made sure the link lights were on on the controllers.

Cheers