Extending volumes

achudacoff · 08-30-2017, 02:02 PM

Hello, I am running CentOS 7.2 in a VM. I started off with 20GB of disk space, but need to extend it.

I've increased the number from 20 to 45 in VMWare client, but now I have to go into the host environment to increase the size there.

I was following an article on how to do this and ran into a blocker with the lvextend command. (https://ma.ttias.be/increase-a-vmwar...oting/#respond)

The goal of this article was to create an additional volume (sda3) and extend sda2 into it. Here is what I have:

Code:

[root@localhost /]# pvscan
  PV /dev/sda2   VG cl              lvm2 [19.00 GiB / 0    free]
  PV /dev/sda3   VG cl              lvm2 [25.00 GiB / 25.00 GiB free]
  Total: 2 [43.99 GiB] / in use: 2 [43.99 GiB] / in no VG: 0 [0   ]
[root@localhost /]#

The command in this article states

Quote:

"lvextend /dev/VolGroupxx /dev/sdXX"

, but I am getting the following error:

Code:

[root@localhost /]# lvextend /dev/cl /dev/sda3
  "/dev/cl": Invalid path for Logical Volume.
  Run `lvextend --help' for more information.
[root@localhost /]#

Thanks in advance for your smart help.

michaelk · 08-30-2017, 02:49 PM

You need to specify the Logical volume. cl is the volume group. Look at the output of the lvdisplay and then pick the one you want to extend.

lvextend /dev/cl/lv_to_be_extended /dev/sda3

achudacoff · 08-30-2017, 02:55 PM

OK, that makes sense. This is what is in the cl directory:

Does it matter which one I select?

Code:

[root@localhost dev]# ll /dev/cl/
total 0
lrwxrwxrwx. 1 root root 7 Aug 30 05:36 root -> ../dm-0
lrwxrwxrwx. 1 root root 7 Aug 30 05:36 swap -> ../dm-1
[root@localhost dev]#

smallpond · 08-30-2017, 02:55 PM

/dev/cl is your PV (physical volume). You also need the name of the LV (logical volume). Run the "lvs" command to list logical volume names. The whole name should be /dev/<pv>/<lv>, something like: /dev/cl/foo.

sundialsvcs · 08-30-2017, 02:58 PM

Use LV/PV commands, not examination of directory contents, to see what LVM considers to be the logical and the physical picture.

All Linux mount-points reside in some logical volume, which is then spread over one-or-more allocations taken from a physical group. Space in a physical group comes from designated partitions on physical drives.

The physical picture concerns itself with devices, not with where the space on those devices is apportioned. Likewise, the logical picture concerns itself with what the OS sees, not the physical resources from whence it comes.

achudacoff · 08-30-2017, 03:25 PM

Does this look right?

Code:

[root@localhost /]# lvs
  LV   VG Attr       LSize  Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root cl -wi-ao---- 17.00g
  swap cl -wi-ao----  2.00g

Code:

[root@localhost /]# pvs
  PV         VG Fmt  Attr PSize  PFree
  /dev/sda2  cl lvm2 a--  19.00g     0
  /dev/sda3  cl lvm2 a--  25.00g 25.00g
[root@localhost /]#

michaelk · 08-30-2017, 03:54 PM

Yes, The logical volume you want to extend is root.

gunrunner45 · 08-30-2017, 03:56 PM

Try,

lvextend -L +25G /dev/cl/root

then

resize2fs /dev/cl/root

!!! · 08-30-2017, 04:07 PM

Also see man for -r
Lots of great tutorials on the www, for quick&easy learning

Welcome both to LQ!!!

achudacoff · 08-30-2017, 04:54 PM

Thanks for having me!

Getting closer.

Code:

[root@localhost /]# resize2fs /dev/cl/root
resize2fs 1.42.9 (28-Dec-2013)
resize2fs: Bad magic number in super-block while trying to open /dev/cl/root
Couldn't find valid filesystem superblock.
[root@localhost /]#

michaelk · 08-30-2017, 05:08 PM

CentOS 7 defaults to xfs. To resize xfs use xfs_growfs using its mount point.

xfs_growfs /dev/mapper/root

achudacoff · 08-30-2017, 06:30 PM

And there it is!

Code:

[root@localhost /]# xfs_growfs /dev/cl/root
meta-data=/dev/mapper/cl-root    isize=512    agcount=4, agsize=1113856 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=0 spinodes=0
data     =                       bsize=4096   blocks=4455424, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal               bsize=4096   blocks=2560, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 4455424 to 10746880
[root@localhost /]#

Thanks guys and gals!