ubuntu - Can't migrate logical volume to newly added physical volumes

I had a partition of 91GB added in a logical volume filled to 61GB. Now I got an external hard drive and added a couple of partitions 43GB and 26GB each to the logical volume.

I now want to move the data to these new pvs and repartition the original 91GB partition. I started out with pvmove -v /dev/sdxx but it says Insufficient free space. Not enough extents. I am confused. My vgdisplay shows me as 91.23GB allocated. Why?

Here's the partition table of my hard disk:

/dev/sda5   91G
/dev/sda1   58G

I have my /home as a logical volume with /dev/sda5 as physical volume.

I now have an external hard drive partition table as follows:

/dev/sdb1    43G
/dev/sdb2    26G
/dev/sdb3    80G

df -h /home gives:

Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/home-home--lvm
                      91G   61G  343M  100% /home

I want to remove /dev/sda5 from /home and repartition it. I have /dev/sdb1 and /dev/sdb2 free, so I want to add them to the lv home. How do I get this done?

Answer

I was initially naive enough to just add /dev/sdb1 and /dev/sdb2. And try pvmove on /dev/sda5.

Here are the steps that solved the problem:

• Boot into maintenance mode, umount the /home




• resize2fs to within the size the new
  partitions can hold. (here 68G).*




• lvresize the logical volume.




• Use pvmove /dev/sda1*




• Now pvremove /dev/sda1



• Format it as you please

  
  
  
  
  
  • -- Both highly time consuming operations.
    You can skip the pvmove and resize the partition following the instructions here. http://www.howtoforge.com/linux_resizing_ext3_partitions
    But then it involves tampering with the partition table, while the data is not backed up. So you better be aware of the risk involved.