Add New Logical Volume

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First, you must have a block device available to you. In this example we will use /dev/mapper/data01, but equally well this could be /dev/sdb or /dev/mmcblk0p1.

First, convert it into a Physical Volume:

# pvcreate /dev/mapper/data01

We can see this using pvs:

# pvs

  PV                   VG   Fmt  Attr  PSize   PFree 
  /dev/sda2            Vsys lvm2 a--    99.52g 30.06g
  /dev/mapper/data01        lvm2 a--   350.00g     0 

Next, we will create a new Volume Group called Vdata to contain this PV:

# vgcreate Vdata01 /dev/mapper/data01

We can see the results of this in pvs and vgs:

# pvs

  PV                   VG    Fmt  Attr PSize   PFree 
  /dev/sda2            Vsys  lvm2 a--   99.52g 30.06g
  /dev/mapper/data01   Vdata lvm2 a--  350.00g     0 

# vgs

  VG    #PV #LV #SN Attr   VSize   VFree 
  Vdata   1   1   0 wz--n- 350.00g     0 
  Vsys    1   8   0 wz--n-  99.52g 30.06g

Lastly, we will create a simple Logical Volume in this VG called Ldata. It will be the maximum available size.

# lvcreate -n Ldata01 -l 100%FREE Vdata01

This is naturally visible using the command lvs:

# lvs

 LV    VG    Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  Ldata Vdata -wi-ao---- 350.00g                                                    
  Lhome Vsys  -wi-ao----   1.91g                                                    
  Llog  Vsys  -wi-ao----   7.63g                                                    
  Lopt  Vsys  -wi-ao----   8.00g                                                    
  Lroot Vsys  -wi-ao----   3.81g                                                    
  Lswap Vsys  -wi-ao----  32.00g                                                    
  Ltemp Vsys  -wi-ao----   7.63g                                                    
  Lusr  Vsys  -wi-ao----   4.67g                                                    
  Lvar  Vsys  -wi-ao----   3.81g                                                    


Excellent. Format this to your preferred filesystem (here, ext4):

# mkfs.ext4 /dev/Vdata01/Ldata01

Then create a mountpoint for this filesystem:

# mkdir /databases/data01

Set the correct permissions at the mount point:

# chown oracle:dba /databases/data01

# chmod 770 /databases/data01

# chmod +s /databases/data01

Edit /etc/fstab So that the filesystem will be mounted on boot:

# vi /etc/fstab

/dev/Vdata01/Ldata01 /databases/data01 ext4 defaults 1 2

Then you can test (and mount) this with:

# mount -a