[CentOS] "No free sectors available" while try to extend logical volumen in a virtual machine running CentOS 6.5

Mon Oct 27 19:56:55 UTC 2014
reynierpm at gmail.com <reynierpm at gmail.com>

I'm trying to extend a logical volume and I'm doing as follow:

1- Run `fdisk -l` command and this is the output:

    Disk /dev/sda: 85.9 GB, 85899345920 bytes 255 heads, 63 sectors/track,
    10443 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes I/O size
    (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00054fc6

    Device Boot      Start         End      Blocks   Id  System
    /dev/sda1   *           1          64      512000   83  Linux
    Partition 1 does not end on cylinder boundary.
    /dev/sda2             64        10444    83371008   8e  Linux LVM

    Disk /dev/mapper/vg_devserver-lv_swap: 4194 MB, 4194304000 bytes 255
    heads, 63 sectors/track, 509 cylinders Units = cylinders of 16065 *
    512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512
    bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk
    identifier: 0x00000000

    Disk /dev/mapper/vg_devserver-lv_root: 27.5 GB, 27523022848 bytes 255
    heads, 63 sectors/track, 3346 cylinders Units = cylinders of 16065 *
    512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512
    bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk
    identifier: 0x00000000

2- Run `fdisk /dev/sda`and print partition using `p`:

    Disk /dev/sda: 85.9 GB, 85899345920 bytes 255 heads, 63 sectors/track,
    10443 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes I/O size
    (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00054fc6

    Device    Boot      Start         End      Blocks   Id  System
    /dev/sda1   *         1           64       512000   83  Linux
    Partition 1 does not end on cylinder boundary.
    /dev/sda2             64         10444    83371008   8e  Linux LVM

Try to create the partition by running:

        Command (m for help): n
        Command action
           e   extended
           p   primary partition (1-4)
        p
        Partition number (1-4): 3
        No free sectors available

I also check the free available space using vgdisplay and watching the Free
PE / Size part near the end and seems like I've free space available (Free
PE / Size 7670 / 29.96 GiB) so I tried to extend the LV by using the
command:lvextend -L+29G /dev/vg_devserver/lv_root but I got some errors and
don't know where to go from here. The first error I see at console is
this /dev/root:
read failed after 0 of 4096 at 27522957312: Input/output error /dev/root:
read failed after 0 of 4096 at 27523014656: Input/output error Couldn't
find device with uuid vSbuSJ-o1Kh-N3ur-JYkM-Ktr4-WEO2-JWe2wS. Cannot change
VG vg_devserver while PVs are missing. Consider vgreduce --removemissing.

Then following the suggestion from the previous command results I run this
other command vgreduce --removemissing vg_devserver but again got this
error: WARNING: Partial LV lv_root needs to be repaired or removed. There
are still partial LVs in VG vg_devserver. To remove them unconditionally
use: vgreduce --removemissing --force. Proceeding to remove empty missing
PVs. so I change the command to the one suggested but once again another
message Removing partial LV lv_root. Logical volume vg_devserver/lv_root
contains a filesystem in use. so at this point I don't know what else to
do,can any give me some ideas or help?

Don't kill me if is something basic I'm not a Linux Admin or a Linux
Advanced User just a developer trying to setup their development
environment. How I can get this done? What I'm doing wrong?

I'm following [this][1] guide because my filesytem is Ext4. Also [this][2]
is helpful too but applies to Ext3 only

 [1]:
http://www.uptimemadeeasy.com/vmware/grow-an-ext4-filesystem-on-a-vmware-esxi-virtual-machine/
 [2]:
http://kb.vmware.com/selfservice/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=1006371