On Sun, Jul 14, 2013 at 12:15:59PM +1000, Jeremy Visser wrote:
On 14/07/13 01:53, Craig Sanders wrote:
and, unlike lvm, with both btrfs and zfs, once you've created the pool you don't need to remember or specify the device names of the disks in the pool unless you're replacing one of them
Can you clarify what you mean by this?
My volume group is /dev/vg_glimfeather. I haven?t interacted with the raw PV, /dev/sda6, in over a year.
here's an example from the lvextend man page: Extends the size of the logical volume "vg01/lvol10" by 54MiB on physi- cal volume /dev/sdk3. This is only possible if /dev/sdk3 is a member of volume group vg01 and there are enough free physical extents in it: lvextend -L +54 /dev/vg01/lvol10 /dev/sdk3 and another from lvresize: Extend a logical volume vg1/lv1 by 16MB using physical extents /dev/sda:0-1 and /dev/sdb:0-1 for allocation of extents: lvresize -L+16M vg1/lv1 /dev/sda:0-1 /dev/sdb:0-1 to extend or resize the volume, you've got to tell it which disk(s) to allocate the free space from. with zfs, you'd just do 'zfs set quota=nnnn pool/volume', and not have to give a damn about which particular disks in the pool the extra space came from. actually, 'set reservation' would be closer in meaning to the lvm commands - 'quota' is is from shared space used by all volumes on that pool so overcommit is possible (even default). e.g. on a 1TB pool, you can create 5 volumes each with quotas of 1TB. 'reservation' actually reserves that amount of space for that volume from the pool. no other volume gets to use that reserved space.
All modern distros autodetect all VGs upon boot.
craig -- craig sanders <cas@taz.net.au> BOFH excuse #57: Groundskeepers stole the root password