[linux-lvm] How to confuse lvm using devfs

[Koos van den Hout]

It seems the lvm tools get confused when there is devfs compiled into the
kernel but it's not mounted at /dev. Twice I had

lvcreate -l 1024 vghm -n home

fail on me with an error about /dev/vghm/home being inacessible. That's
simply because it was not there.

When I created /dev/vghm/home with the same data as /devices/vghm/home
it wasn't available right away (according to vgdisplay, the extents
were allocated, but lvdisplay did not show the logical volume). When I reran
vgscan (and maybe rebooted in the process, I have rebooted lots of times)
it showed up and worked. The device is formatted with reiserfs now and
mounted.

Now, when I try to display the volume info:

root at NEWgosper:~# lvdisplay /devices/vghm/home 
lvdisplay -- invalid logical volume name "/devices/vghm/home"


root at NEWgosper:~# lvdisplay /dev/vghm/home 
--- Logical volume ---
LV Name                /dev/vghm/home
VG Name                vghm
LV Write Access        read/write
LV Status              available
LV #                   1
# open                 1
LV Size                4.00 GB
Current LE             1024
Allocated LE           1024
Allocation             next free
Read ahead sectors     120
Block device           58:1

root at NEWgosper:~# ls -l /dev/vghm/home /devices/vghm/home
brw-r-----    1 root     root      58,   1 Apr 29 01:23 /dev/vghm/home
brw-r-----    1 root     root      58,   1 Jan  1  1970 /devices/vghm/home

Kernel 2.4.18, devfs compiled in but mounted on /devices and not on /dev
(just testing with devfs).

Logical Volume Manager 1.0
Heinz Mauelshagen, Sistina Software  14/08/2001 (IOP 10)

                                     Koos van den Hout

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