Owner's Manual

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• The external storage logical volumes appear as SCSI devices, and each
node is configured with the same number of LUNs/virtual disks.
For example, if the node is configured with a SCSI drive or RAID
container attached to a Fibre Channel storage device with three
logical disks,
sda identifies the node’s RAID container or internal drive,
and
emcpowera , emcpowerb , and emcpowerc identify the LUNs
(or PowerPath pseudo devices).
If the node is configured with a SCSI drive or RAID container attached to
a Direct-attached SAS or iSCSI storage device with three virtual disks,
sda
identifies the node’s RAID container or internal drive, and sdb , sdc , and
sdd identify the external storage logical volumes.
6 If the external storage devices do not appear in the /proc/partitions file, reboot
the node.
Adjusting Disk Partitions for Linux Systems
In Linux, align the partition table before data is written to the LUN/virtual disk, as
the partition map will be rewritten and all data on the LUN/virtual disk destroyed.
EXAMPLE: fdisk Utility Arguments
The following example indicates the arguments for the fdisk utility. In this
example, the LUN is mapped to
/dev/emcpowera , and the LUN stripe element size
is 128 blocks.
NOTE: In this example, the disk /dev/emcpowera already has a primary partition
/dev/emcpowera1 created. In the case of the MD3000/MD3000i, this process would
need to be performed on /dev/sdb1.
fdisk /dev/emcpowera
NOTE: A partition needs to be created on /dev/emcpowera before performing the
following steps.
x # expert mode
b # adjust starting block number
1 # choose partition 1
128 # set it to 128, (This is the default stripe element
size on Dell|EMC CX Series Fibre Channel Storage)
w # write the new partition