create a single partition

[matteedee]

Hi Im following an installation guide (Oracle ASM) which requires me to create a partition on the disk and gives the following example:

fdisk /dev/mapper/< alias >
kpartx /dev/mapper/< alias >< partition >

Im struggelling what <alias> and <partition> need to be substituted for, I have tried to look this up but all that is returned are bug fixes etc... generally things that dont make much sense to a newbie like me.

Can someone help me/explain this please?

The following info may help?

[root@localhost ~]# cd /dev/mapper
[root@localhost mapper]# ls
control  VolGroup00-LogVol00  VolGroup00-LogVol01

[root@localhost mapper]# /sbin/fdisk -l

Disk /dev/sda: 64.4 GB, 64424509440 bytes
255 heads, 63 sectors/track, 7832 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          13      104391   83  Linux
/dev/sda2              14        7832    62806117+  8e  Linux LVM
[root@localhost mapper]#

[matteedee]

anyone?...

[coopstah13]

You can't use existing partition? You only have one disk sda. The mapper stuff is for logical volumes. If you create new partition structure you might mess up the installation.

[matteedee]

im confused.. could you explain what you mean??

Or, lets assume I have another disk called sdb ... and i wanted to do it on that disk instead?

[MikeTbob]

If you want to create partitions, look at the man page for fdisk

man fdisk

You can also get Parted Magic and use that to create partitions.

[matteedee]

Can someone please just help answer the actual origional question I asked...

And give me an example of how I would use the two commands I origionally posted, ie... how does the <alias> and <partition> parts of that command work

plzzz

[coopstah13]

VolGroup00-LogVol00 VolGroup00-LogVol01

VolGroup00 is the logical volume group, LogVol00/LogVol01 are the logical volumes in this group, most likely one is root partition and one is swap partition

also, things under /dev/mapper are for logical volumes, you can use lvdisplay, pvdisplay and see what your logical volumes are and physical volumes and then you can figure out what is in there

if you need to create a separate partition in LVM, you will have to shrink one or both of the logical volumes to create space to create a new logical volume

I don't know what your distro is, but I've used this with both arch and ubuntu server https://wiki.archlinux.org/index.php/Lvm

[matteedee]

... how does the <alias> and <partition> parts of that command work

[coopstah13]

i'm not sure, my best guess is that alias would be VolGroup00 and partition would be LogVol00, but I really have no idea

I've personally never heard of using fdisk on logical volume