Dell PowerVault MD Series, Administrator'S Manual

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Add A New Partition To Device Mapper
The
kpartx
command adds the new fdisk partition to the Device Mapper list of usable partitions. See examples below,
where
mpath<x>
is the device node on which the partition was created.
# kpartx –a /dev/mapper/mpath<x>
If successful, the command does not display an output. To verify success and view exact partition naming, you can use
these commands to see the full partition names assigned.
# cd /dev/mapper# ls
The following are some examples of the general mapping formats:
• On Red Hat Enterprise Linux (RHEL) hosts, a partition node has the format:/dev/mapper/mpath<x>p<y>
Where <x> is the alphabetic number for the multipathing device, <y> is the partition number for this device.
• On SUSE Linux Enterprise Server (SLES) 11.x hosts, a partition node has the format:/dev/mapper/mpath<x>-
part<y>
Where <x> is letter(s) assigned to the multipathing device and <y> is the partition number.
• On SLES 10.3 hosts, a partition node has the format: /dev/mapper/mpath<x>_part<y>
Where <x> is the letter(s) assigned to the multipathing device and <y> is the partition number.
NOTE: After creating a partition on a device capable of multipathing, all I/O operations, including file system
creation, raw I/O and file system I/O, must be done through the partition node, and not through the multipathing
device nodes.
Create A File System On A Device Mapper Partition
Use the standard
mkfs
command to create the file system on the newly created Device Mapper partition.
For example:
# mkfs –t <filesystem type> /dev/mapper/<partition node>
where
<partition node>
is the partition on which the file system is created.
Mount A Device Mapper Partition
Use the standard mount command to mount the Device Mapper partition, as shown below:
# mount /dev/mapper/<partition_node> <mounting point>
Ready For Use
The newly created virtual disks created on the MD Series storage array are now setup and ready to be used. Future
reboots automatically find multipathing devices along with their partitions.
NOTE: To ensure data integrity protection, reboot a Linux host server attached to an MD Series storage array using
the procedure given below.
Linux Host Server Reboot Best Practices
Its is recommended that you follow the procedures given below when you reboot your Linux host server using Device
Mapper multipathing with an MD Series storage array.
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