about the maximum number of lvm

[Rambo_1]

Hi ,
the default lv number in each vg is 255. can I create a vg that lv number contained more than 255 ?

Thanks

[Dino_4]

Hi,

255 is the max.

Look in `man vgcreate` at the option `-l` (ell)

HTH

[Bruno Ganino]

I believe that not possible.
But read this doc
http://publib-b.boulder.ibm.com/Redbooks.nsf/RedbookAbstracts/tips0128.html?Open
Bruno

[Joseph Loo]

hi,

i do not think that is possible as stated that lvol[n] must be between the range of 1 to 255.

# man lvcreate

regards.

[Dino_4]

Hi again,

after thinking about that issue, i came to an explanation why.

Under /dev/$VG-NAME, two devicefiles will be created for each lvol.

The minornumber will hold the vg-no and lvol-no, and since there are only 2 digits-hex for the lvol, u can't go higher than 255, because u can only address that much.

HTH

[twang]

The Max LV is 255, we cannot exceed the maximum number of logical volumes.
You may take a look at the manpage of vgcreate:
VGCREATE (1M)

-l max_lv Set the maximum number of logical volumes
that the volume group is allowed to contain.
The default value for max_lv is 255. The maximum
number of logical volumes can be a value in the
range 1 to 255.

-p max_pv Set the maximum number of physical volumes
that the volume group is allowed to contain.
The default value for max_pv is 16. The
maximum number of physical volumes can be a
value in the range 1 to 255.

[hpuxrox]

I guess the question is WHY? I have found it much better to assign as few lvols per VG as posisble to reduce the LVM overhead per volume group. I have see this question come up before at a place I worked. I got an engeneering document to create 386 lvols in each volume groups. It was soon aparent, the engeneer had no idea what he was doing...

[Rambo_1]

Hi Yates H. Randall
You mean it's possible to create lv number more than 255 ?

[Joseph Loo]

hi,

u should really read this article:

http://www2.itrc.hp.com/service/iv/node.do?source=search&node=prodITRC%2FWW_Start%2FN1%7C20%7C3%7C1%7C4%7C2

if someone is telling u otherwise and not from the horses' mouth (HP), u should really be cautious.

if u do need confirmation, ask HP.

regards.