Configuring Rdac (Mpp) - IBM System Storage DS3500 Introduction And Implementation Manual

Draft Document for Review March 28, 2011 12:24 pm
NumLunObjects: 2
Another way to list the all available SCSI devices is by using the lsscsi command as is shown
in Example 20-7. This will show each path and the Virtual Disk created by RDAC.
Example 20-7 lsscsi command
# lsscsi
[0:0:0:0]
[1:0:0:0]
[2:0:0:0]
[3:0:0:0]
[4:0:0:0]
[5:0:0:0]
[6:0:0:0]
Now SuSE OS should see the new /dev/sdb disk as shown in Example 20-8:
Example 20-8 fdisk -l Output
# fdisk -l
Disk /dev/sda: 73.4 GB, 73407488000 bytes
255 heads, 63 sectors/track, 8924 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x04b643b3
Device Boot
/dev/sda1
/dev/sda2
Disk /dev/sdb: 64.4 GB, 64424509440 bytes
64 heads, 32 sectors/track, 61440 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes
Disk identifier: 0x00000000
Disk /dev/sdb doesn't contain a valid partition table

20.1.5 Configuring RDAC (MPP)

The Redundant Disk Array Controller Driver (a.k.a. Multi-Path Proxy Driver or MPP) adds a
new layer in the Linux OS driver stack. It is a combination of 2 drivers, one, a upper level
driver and the other, a virtual Host Bus Adapter (HBA) driver.
The upper level driver has the same design role as an "sd" or "sg" driver on Linux. It is
responsible for the management of multiple paths to the disk array.
The virtual HBA driver is a Linux SCSI lower level driver. It sits at the same level of the driver
stack as any driver for a physical QLogic or LSI fibre channel HBA.
Path #1: LunPathDevice: present
DevState: OPTIMAL
RemoveState: 0x0 StartState: 0x1 PowerState: 0x0
Path #2: LunPathDevice: present
DevState: OPTIMAL
RemoveState: 0x0 StartState: 0x1 PowerState: 0x0
disk IBM-ESXS ST9500430SS
cd/dvd HL-DT-ST RW/DVD GCC-T10N 1.00 /dev/sr0
disk IBM 1746
disk IBM 1746
disk IBM 1746
disk IBM VirtualDisk
disk IBM 1746
Start
1
* 263
BD11 /dev/sda
FAStT 1070 -
FAStT 1070 -
FAStT 1070 -
1070 /dev/sdb
FAStT 1070 -
End Blocks Id System
262 2104483+ 82 Linux swap / Solaris
8924 69577515 83 Linux
Chapter 20. SuSE Linux configuration guide
Linux Config.fm
RoundRobinIndex: 0
615