topic Re: vgextend Linux FS in Operating System - Linux

vgextend Linux FS

Duffs — Tue, 13 Apr 2010 08:11:33 GMT

Hi,

I have got a RH Linux FS (listed below) that has been created from space presented from an EVA. I need to extend this FS by creating another LUN (of 50G) from the EVA, presenting it to the server and then extending the VG and FS accordingly.

/dev/mapper/vg02-lvol0
145G 131G 6.5G 96% /cuar2

My problem however is that when I run a vgdisplay on the FS I get the following:
# vgdisplay vg02
Volume group "vg02" not found

It is not present in the 'vgdisplay -v' yet the FS appears fine:

ll /dev/mapper/vg02-lvol0
brw-rw---- 1 root disk 253, 11 Jul 29 2009 /dev/mapper/vg02-lvol0

Is there any way of re-scanning the vg so it can be seen from the vgdisplay in order for me to extend this FS?

R,
D.

Re: vgextend Linux FS

Jean-Yves Picard — Tue, 13 Apr 2010 08:38:27 GMT

Hello,

Does vg02 appear whe running vgs or pvscan ?
Is data in /cuar2 FS still available ?

Jean-Yves

Re: vgextend Linux FS

Duffs — Tue, 13 Apr 2010 08:44:55 GMT

Hi,

No, vg02 does not appear when vgs or pvscan are run but the data on /cuar2 is fine.

R,
D.

Re: vgextend Linux FS

nightwich — Wed, 14 Apr 2010 13:14:31 GMT

Hi,

I think you need to do a:

vgdisplay -v /dev/mapper/vg02-lvol0

also try vgdisplay -v

Regards.

Re: vgextend Linux FS

Duffs — Wed, 14 Apr 2010 13:18:17 GMT

Hi

# vgdisplay -v /dev/mapper/vg02-lvol0
Using volume group(s) on command line
Invalid volume group name: mapper/vg02-lvol0

.....and as I mentioned in my above post the 'vgdisplay -v' does not show the vg either.

R,
D.

Re: vgextend Linux FS

nightwich — Wed, 14 Apr 2010 14:49:21 GMT

ok

try strings /etc/lvmtab

If the vg in not in lvmtab

Try mv /etc/lvmtab /etc/lvmtab.BCK

And then vgscan -a

This is risky command.

Hope this helps

Re: vgextend Linux FS

Matti_Kurkela — Thu, 15 Apr 2010 06:27:51 GMT

@nightwich: Linux LVM does not have /etc/lvmtab. Don't try to blindly apply HP-UX LVM instructions to Linux.

In Linux, vgscan is not so risky operation as in HP-UX. Try running "vgscan -vvv" to get a lot of information about the scan process. If it says it's filtering out some devices, check the /etc/lvm/lvm.conf file for customizations.

You might also check the state of the device-mapper, the low-level system service that is used by LVM:

dmsetup info /dev/mapper/vg02-lvol0
dmsetup table /dev/mapper/vg02-lvol0

MK

Re: vgextend Linux FS

Ralph Grothe — Thu, 15 Apr 2010 13:52:30 GMT

Hi R.

as Matti wrote, often applied filters are the cause for seemingly undetected PVs.

But you wouldn't have to grep for "filter"
but rather for "skip".

e.g.
I needed to deliberately apply such a filter in order to use a DRBD and to prevent LVM from grabbing the sub meta devices that form the DRBD.

# grep ^\ *filter /etc/lvm/lvm.conf
filter = [ "a|^/dev/md[145]$|", "a|/dev/drbd0|", "r/.*/" ]

Because of the trailing catch all "remove" pattern "r/.*/" I get lots of devices that are ignored by LVM scans.

# pvscan -vvv 2>&1|grep -i skip|tail
/dev/ram14: Skipping (regex)
/dev/ram15: Skipping (regex)
/dev/sdb: Skipping (regex)
/dev/sdb1: Skipping (regex)
/dev/sdb2: Skipping (regex)
/dev/sdb3: Skipping (regex)
/dev/sdb4: Skipping (regex)
/dev/sdb5: Skipping (regex)
/dev/sdb6: Skipping (regex)
/dev/sdb7: Skipping (regex)

Re: vgextend Linux FS

Duffs — Wed, 21 Apr 2010 13:52:06 GMT

Hi,

Thanks for the feedback but I am still unable to see the vg although the state of the lvol appears active:

[root@rhmidlog ~]# dmsetup info /dev/mapper/vg02-lvol0
Name: vg02-lvol0
State: ACTIVE
Tables present: LIVE
Open count: 1
Event number: 0
Major, minor: 253, 11
Number of targets: 1
UUID: LVM-Yr9KH40fpQcgL3nhStugbwo0vd4uNpCQb38gQP1NGItXEsFHDzTkpaXDbi7y0S2H

[root@rhmidlog ~]# dmsetup table /dev/mapper/vg02-lvol0
0 307200000 linear 8:32 384
[root@rhmidlog ~]#
[root@rhmidlog ~]# vgs
VG #PV #LV #SN Attr VSize VFree
VolGroup00 2 9 0 wz--n- 184.81G 928.00M
VolGroup01 1 1 0 wz--n- 100.00G 99.02G

pvscan -vvv 2>&1|grep -i skip|tail
/dev/md25: Skipping (sysfs)
/dev/md26: Skipping (sysfs)
/dev/md27: Skipping (sysfs)
/dev/md28: Skipping (sysfs)
/dev/md29: Skipping (sysfs)
/dev/md30: Skipping (sysfs)
/dev/md31: Skipping (sysfs)
/dev/sdc: Skipping: Partition table signature found
/dev/sdd: Skipping: Partition table signature found
/dev/sde: Skipping: Partition table signature found

R,
D.

Re: vgextend Linux FS

Steven E. Protter — Wed, 21 Apr 2010 17:15:37 GMT

Shalom,

Suggest: vgchange -a y /dev/vg02

SEP