Error creating mirrored file system

[Yogeeraj_1]

Hello experts,

I was creating a new Mirrored File system on my server using SAM when i got the following error message:
----------------------------------------------
The command used to create logical volumes, /sbin/lvcreate, has
failed. The stderr output from the command is shown below. The
logical volume has not been created.

lvcreate: Not enough free physical extents available.
Logical volume "/dev/vg00/lv_d06" could not be extended.
Run the "lvextend" command to add mirror copies to the Logical
Volume.
----------------------------------------------

Is there a way to create these file systems manually? How do i know if there are enough space available for creating the mirrored file system? My VG00 and VG01 have each 2 disk (18GB)

thank you for your replies

regards
yogeeraj

[Michael Tully · Accepted solution]

Hi,

The first thing you need to do is
work out if you have enough space.
To do this you need to use the
output of 'vgdisplay' to see

For example on my server here I have
this output, where the number of
free PE is the number of extents
available. If this number is less
than the Alloc PE you can mirror
all of the logical volumes in this
group easily. If the number is less
then I suggest you post the output of
'vgdisplay -v' so we can view the output.
I think that you are trying to mirror
to the same disk and that is why it is
coming up with the error. The number of
disks is shown in the row of 'Cur LV'

--- Volume groups ---
VG Name /dev/vg00
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 8
Open LV 8
Max PV 16
Cur PV 2
Act PV 2
Max PE per PV 4350
VGDA 4
PE Size (Mbytes) 8
Total PE 8680
Alloc PE 1546
Free PE 7134
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0

To create a mirrored copy of this you
need to first have a second disk allocated
to the volume group. Have a look at the
information that I posted in this thread
yesterday. To do a second volume group the same rules apply.

http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0x61dc9200caded5118ff40090279cd0f9,00.html

HTH
-Michael

[Michael Tully]

Hi (again),

In my previous post I suggested that
"the same rules" apply when mirroring
subsequent logical volumes and groups.
When you are mirroring vg01 for example
you do not use the 'mkboot' commands.

-Michael

[Michael Tully]

Hi,

The volumes that have the allocated PE
as double the number of Current LE
indicate that these are mirrored.

Neither of your volume groups have
enough free PE to mirror all of the
volumes. For the most part, you will
need to find out which volumes require
the mirroring over others, or additionally
add further disk to mirror the lot.

It looks like /dev/vg00 has the operating
system already mirrored. You can check
this by running the 'lvlnboot -v' command.
If the output is like the below, no problem.
If it is not, please post the output of that.

# lvlnboot -v
Boot Definitions for Volume Group /dev/vg00:
Physical Volumes belonging in Root Volume Group:
/dev/dsk/c1t15d0 (0/0/1/1.15.0) -- Boot Disk
/dev/dsk/c3t15d0 (0/0/2/1.15.0) -- Boot Disk
Boot: lvol1 on: /dev/dsk/c1t15d0
/dev/dsk/c3t15d0
Root: lvol3 on: /dev/dsk/c1t15d0
/dev/dsk/c3t15d0
Swap: lvol2 on: /dev/dsk/c1t15d0
/dev/dsk/c3t15d0
Dump: lvol2 on: /dev/dsk/c1t15d0, 0

HTH
-Michael

[Yogeeraj_1]

Hi again Michael,

Please find below, the output you asked. I guess my boot disk are already mirrorred.

What are recommended steps? I normally use SAM. Is it better to do it manually from the command prompt? For sure it is not recommended to mirror LVs on the same disks. I guess i will need to first verify how much space is left on the other disk before creating a mirrored LV.

In SAM, i don't recall having come across any section where it tell me where i will be putting my mirror!! Cn you please tell me how will i know if the mirrored LV will be on same disk or the other disk from the same VG?

One more question. If i do swlist, will i know if i have Online JFS on my system?
If i don't have it, which of these options for mounting my file system will not work"
-o rw,suid,delaylog,nodatainlog
-o rw,suid,convosync=direct,mincache=direct,delaylog,nodatainlog

Thanks a lot again

Kind regards
Yogeeraj
----------------------------------------------
# lvlnboot -v
Boot Definitions for Volume Group /dev/vg00:
Physical Volumes belonging in Root Volume Group:
/dev/dsk/c1t2d0 (0/0/1/1.2.0) -- Boot Disk
/dev/dsk/c2t2d0 (0/0/2/0.2.0) -- Boot Disk
Boot: lvol1 on: /dev/dsk/c1t2d0
/dev/dsk/c2t2d0
Root: lvol3 on: /dev/dsk/c1t2d0
/dev/dsk/c2t2d0
Swap: lvol2 on: /dev/dsk/c1t2d0
/dev/dsk/c2t2d0
Dump: lvol2 on: /dev/dsk/c1t2d0, 0

[Michael Tully]

Hi,

First off, the output of 'lvlnboot' is exactly
what you need, so no problems there. When doing
any sort of LVM maintenance it always better
to do at the command line level if you can. One
other advantage of this is that you have total
control of what is going on. SAM will not do
everything, but most things.

To check you can run the 'lvdisplay -v /dev/vgxx/yourlv'
to find exactly what disks are being used as
the mirror.

To check on On-Line JFS, you can run the 'swlist'
command, i.e. swlist -l product

We don't have on-line JFS, but I am fairly sure you need it for option 2.

HTH
-Michael

[Mary Ann Lipa]

Hi Yoogeraj...

I have attached a file for your reference.

Hope this will be useful for your mirroring

[Yogeeraj_1]

hello michael,

In the "vgdisplay -v", that i posted previosuly, i find something rather strange. Can you please explain to me this part?
=================================
LV Name /dev/vg00/lv_d01
LV Status available/syncd
LV Size (Mbytes) 5120
Current LE 1280
Allocated PE 768
Used PV 1

LV Name /dev/vg00/lv_d01
LV Status available/syncd
LV Size (Mbytes) 5120
Current LE 1280
Allocated PE 1280
Used PV 2
=================================
BDF shows me lv_d01 mounted on /d01
# bdf
Filesystem kbytes used avail %used Mounted on
/dev/vg00/lv_d01 5242880 5015703 213000 96% /d01
=================================

The thing is that i will need to review all my file systems since my server will soon be going live. I need to have all my Oracle FS to be mirrored. I will need to remove some temporary LVs. I don't think i can add additional internal disks - I have a L-class.

regards
Yogeeraj