vgcreate not working

[Scott Frye_1]

I ran pvcreate, I created my directory (/dev/vg01), I ran the mknod command. All appeared to work fine. Now I run 'vgcreate -s 8 /dev/vg01 /dev/dsk/c20t0d0' and I get this message:
vgcreate: Physical Volume "/dev/dsk/c20t0d0" contains no LVM information

What is this telling me? What did I do wrong?

Thanks

[Pete Randall]

Scott,

Re-check your pvcreate command. Did you specify the right device?


Pete

[Thierry Poels_1]

hi,

forgot pvcreate on the disk?

regards,
Thierry.

[john kingsley · Accepted solution]

pvcreate /dev/rdsk/
mkdir /dev/vg01
mknod /dev/vg01/group c 64 0x010000
vgcreate -s 8 /dev/vg01 /dev/dsk/

Make sure you use raw device file with pvcreate.

Double check that you used the correct minor number with mknod.

Do you see the disk when you run "ioscan -fnC disk"?

[Geoff Wild]

Sounds like it contains no LVM info...

Make sure it's not in a volumegroup:

strings /etc/lvmtab |grep c20t0d0

Anything from:
diskinfo /dev/rdsk/c20t0d0

Create it again:
pvcreate -f /dev/rdsk/c20t0d0
pvdisplay /dev/dsk/c20t0d0

Then try the vgcreate again...


Rgds...Geoff

[Tim Sanko]

it sounds like you have exceeded the vgmax in your kernel tuning parameters. Go into sam and check to see if you have vgmax set to something reasonable for your environment.

My vgmax on one box is 255 the absolute max, and one is 86 each to the system needs...

[Jeff Schussele]

Hi,

What does
diskinfo /dev/rdsk/c20t0d0
return?

Did you use -f on the pvcreate command. If it ever had LVM or even VxVM info on it you have to "force" the pvcreate. It's a safety factor in case you specify the wrong PV in the pvcreate command.

Rgds,
Jeff

[Todd McDaniel_1]

I think Tim means... maxvgs


Also, make doubly sure your disk is visible and check for NO_HW in an ioscan...

Use diskinfo to be sure it is there and not just a phantom device in your /dev/dsk directory.


I set mine to 255 as a default... I believe the REAL default is something like 64 vgs...

[Steve Post]

I see you are creating vg01, that sounds like this is the second volume you are creating after vg00. I.e. total volume groups = 2. If that's the case, MAX_VGS(or whatever its called) will be well above 2. You can to sam to take a look under kernel parameters.

So lets look at something else....

Run "ls -l /dev/vg*/group"
You get all of the group files. Are any of # in the 0x0#0000 columns the same? They shouldn't be. You probably already know this. But still...I got stuck once because I inadvertantly tried to use the same number for a volume I was importing.

0x030000 Dec 16 2001 /dev/vgssd5/group

steve

[Dietmar Konermann]

Scott,

no idea if the problem is still present or if you are still watching this thread.

Just an addtl. note... if vgcreate reports "contains no LVM information" then this is typically the absolute truth.

So you should have a closer look at your pvcreate command. Take care... I remember situations where pvcreate failed without reporting an error message.

A sucsessful pvcreate always prints the message:
'Physical volume "%s" has been successfully created.'

Otherwise something is wrong... typically the disk has some kind of problem.

Best regards...
Dietmar.