How to resize a virtual disk on a Linux system

Virtual systems are much more flexible than physical servers, for instance you can
resize the virtual disk also you need to update LVM configurations.

[root@db2test ~]# pvs
  /dev/cdrom: open failed: No medium found
  PV         VG         Fmt  Attr PSize  PFree
  /dev/sda2  VolGroup00 lvm2 a-   14.88G  3.38G
  /dev/sdb   VGDATOS    lvm2 a-   11.00G 96.00M

[root@db2test ~]# pvresize /dev/sdb
  /dev/cdrom: open failed: No medium found
  Physical volume "/dev/sdb" changed
  1 physical volume(s) resized / 0 physical volume(s) not resized

[root@db2test ~]# lvresize -L +1G /dev/VGDATOS/DB2
  /dev/cdrom: open failed: No medium found
  Extending logical volume DB2 to 9.90 GB
  Logical volume DB2 successfully resized

[root@db2test ~]# resize2fs /dev/mapper/VGDATOS-DB2
resize2fs 1.39 (29-May-2006)
Filesystem at /dev/mapper/VGDATOS-DB2 is mounted on /home/db2inst1; on-line resizing required
Performing an on-line resize of /dev/mapper/VGDATOS-DB2 to 2595840 (4k) blocks.
The filesystem on /dev/mapper/VGDATOS-DB2 is now 2595840 blocks long.