[linux-lvm] pvresize after extending RAID array

[Peter Daum]

I have a physical volume consisting of 1 hardware raid array (/dev/sdb).
Now I added some disks to the raid array, extending its size from 4.5
to ~6 TB. The kernel (Linux 2.6.16.51) now correctly reports the new
device size:

# cat /sys/block/sdb/size
12695042048

>From reading the manuals I got the impression, that all that is needed
to be able to use the additional space is "pvresize /dev/sdb".
Unfortunately, it looks like pvresize insists on the old device size:

# pvresize -v  -d  /dev/sdb
File descriptor 3 left open
    Using physical volume(s) on command line
    Archiving volume group "raid6_12" metadata (seqno 19).
    No change to size of physical volume /dev/sdb.
    Resizing volume "/dev/sdb" to 9765416576 sectors.
    Updating physical volume "/dev/sdb"
    Creating volume group backup "/etc/lvm/backup/raid6_12" (seqno 20).
  Physical volume "/dev/sdb" changed
  1 physical volume(s) resized / 0 physical volume(s) not resized

Did I miss something? Is there anything to worry about or should I just
go ahead and set the new device size manually:
# pvresize -v  -d --setphysicalvolumesize 6347521024k /dev/sdb
File descriptor 3 left open
    Using physical volume(s) on command line
    Archiving volume group "raid6_12" metadata (seqno 22).
  WARNING: /dev/sdb: Overriding real size. You could lose data.
    /dev/sdb: Pretending size is 12695042048 not 12695035904 sectors.
    No change to size of physical volume /dev/sdb.
    Resizing volume "/dev/sdb" to 12695041664 sectors.
    Updating physical volume "/dev/sdb"
    Creating volume group backup "/etc/lvm/backup/raid6_12" (seqno 23).
  Physical volume "/dev/sdb" changed
  1 physical volume(s) resized / 0 physical volume(s) not resized

In this case, pvresize comes up with yet another size for the device
(12695035904 sectors) - is this the actual size of the device minus
the space needed for lvm's metadata? Should I manually set to this?

Any comments?

Regards,
                          Peter Daum