Ubuntu – How to create a LVM Partition/physical volume > 2TB

hard drivelvmpartitioning

I was following this tutorial found here: How to set up multiple hard drives as one volume?

Which was working out great however i have a 3TB drive and every time i create the partition (whether it be via fdisk or gparted), after i start creating the volumes in LVM, my partition is re-sized to 2TB and the partition table becomes msdos which doesn't allow me to create any more partitions or to extend the current partition.

Is there a way that i can get a 3TB drive working with LVM?

Thanks,
Adam

Best Answer

It seems that by creating a partition to use as a physical volume in LVM, we're limited to a 2TB volume size. This is due to the limitations in the legacy MSDOS partition table system managed by fdisk and why one should use GPT.

Fortunately, LVM also understands plain devices without a partition table. This has the drawback that you'll have to use the whole device as physical volume, but that's exactly what I want to achieve.

To erase the current partition table execute the following command (Warning: this effectively erases all contents on the disk!):

sudo dd if=/dev/zero of=PhysicalVolume bs=512 count=1

replacing PhysicalVolume with your device path, e.g. /dev/sdb. Then run

sudo partprobe

to let the kernel re-read the new now non-existing partition table.

Now actually format it as an LVM physical volume:

sudo pvcreate PhysicalVolume

(again, replace PhysicalVolume with your device path)

This is based on the information mentioned in the manpage of pvcreate:

DESCRIPTION
       pvcreate initializes PhysicalVolume for later use by the Logical Volume
       Manager  (LVM).   Each  PhysicalVolume  can  be a disk partition, whole
       disk, meta device, or loopback file.   For  DOS  disk  partitions,  the
       partition  id  should  be  set  to 0x8e using fdisk(8), cfdisk(8), or a
       equivalent.  For whole disk devices only the partition  table  must  be
       erased, which will effectively destroy all data on that disk.  This can
       be done by zeroing the first sector with:

       dd if=/dev/zero of=PhysicalVolume bs=512 count=1
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