I have a server with 4 1TB drives in LVM as shown below. The server is a openvz hardware node with a dozen or so openvz containers. At this time each container uses one disk only. This was designed at the time to maintain most control and separation over the disk io load.
# pvdisplay -s Device "/dev/sdd1" has a capacity of 227.51 GiB Device "/dev/sdc1" has a capacity of 427.51 GiB Device "/dev/sdb1" has a capacity of 427.51 GiB Device "/dev/sda2" has a capacity of 407.02 GiB
ATM each PV is set up with it's own separate VG:
# vgdisplay -s "vg04" 931.51 GiB [704.00 GiB used / 227.51 GiB free] "vg03" 931.51 GiB [504.00 GiB used / 427.51 GiB free] "vg02" 931.51 GiB [504.00 GiB used / 427.51 GiB free] "vg01" 931.02 GiB [524.00 GiB used / 407.02 GiB free]
A number of LV's exist over these VG's:
# lvdisplay | grep Name LV Name /dev/vg04/swap VG Name vg04 LV Name /dev/vg04/vz VG Name vg04 LV Name /dev/vg03/swap VG Name vg03 LV Name /dev/vg03/vz VG Name vg03 LV Name /dev/vg02/swap VG Name vg02 LV Name /dev/vg02/vz VG Name vg02 LV Name /dev/vg01/swap VG Name vg01 LV Name /dev/vg01/root VG Name vg01 LV Name /dev/vg01/vz VG Name vg01
One container has now grown to a size where I need to split it over two disks in order to handle the load.
Essentially I'd like to merge two LV's - /dev/vg03/vz and /dev/vg04/vz into one LV striped over two disks.
How do I best accomplish that? Would vgmerge be able to do this? The manpage for vgmerge is rather brief and I've not been able to find any more in-depth discussion of it's use.
In the end I could accomplish the objective by moving things around but there is a lot of data in play and these are production servers so I'd rather try to avoid that if possible.