Centos_Lvm expand capacity without restarting CentOS

• Rescan the new disk(/dev/sdb):

#ls /sys/class/scsi_host/
host0  host1  host2
[root@db210_13:56:14 /data]  
#echo "- - -" > /sys/class/scsi_host/host0/scan
[root@db210_13:57:57 /data]  
#echo "- - -" > /sys/class/scsi_host/host1/scan
[root@db210_13:57:57 /data]  
#echo "- - -" > /sys/class/scsi_host/host2/scan
[root@db210_13:57:58 /data]  
#fdisk -l

Disk /dev/sda: 64.4 GB, 64424509440 bytes, 125829120 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x00084df7

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048     1026047      512000   83  Linux
/dev/sda2         1026048     5222399     2098176   82  Linux swap / Solaris
/dev/sda3         5222400    86259711    40518656   83  Linux
/dev/sda4        86259712   125829119    19784704    5  Extended
/dev/sda5        86261760   125829119    19783680   83  Linux
--- new disk is  /dev/sdb ---
Disk /dev/sdb: 214.7 GB, 214748364800 bytes, 419430400 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

**Disk /dev/sdc: 536.9 GB**, 536870912000 bytes, 1048576000 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0xb4f30c82

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1            2048  1048575999   524286976   83  Linux

• format the new disk

[root@db210_12:15:04 /backup] 
#fdisk /dev/sdb
Welcome to fdisk (util-linux 2.23.2).

Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0xb4f30c82.

Command (m for help): n
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): p
Partition number (1-4, default 1):
First sector (2048-1048575999, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-1048575999, default 1048575999):
Using default value 1048575999
Partition 1 of type Linux and of size 500 GiB is set

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

• Create a PV

[root@db210_12:15:23 /backup] 
#pvcreate /dev/sdb1
  Physical volume "/dev/sdb1" successfully created.
[root@db210_12:15:47 /backup] 
#pvs
  PV         VG Fmt  Attr PSize    PFree  
  /dev/sdb1     lvm2 ---  <500.00g <500.00g

• Gets the existing VG name

#vgdisplay 
  --- Volume group ---
  VG Name               MySQL
  System ID             
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  3
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                1
  Open LV               1
  Max PV                0
  Cur PV                2
  Act PV                2
  VG Size               699.99 GiB
  PE Size               4.00 MiB
  Total PE              179198
  Alloc PE / Size       127744 / 499.00 GiB
  Free  PE / Size       51454 / 200.99 GiB
  VG UUID               VkivHp-IPdu-bPwW-kRNx-UUB3-ZWj1-SJ9gjo
   

• Add /dev/sdb1 to VG(MySQL)

[root@db210_12:39:53 /data]  
#vgextend MySQL /dev/sdb1
  Volume group "MySQL" successfully extended

-Expand capacity to LV

#df -h
Filesystem               Size  Used Avail Use% Mounted on
/dev/sda3                 39G   12G   28G  30% /
devtmpfs                 3.9G     0  3.9G   0% /dev
tmpfs                    3.9G     0  3.9G   0% /dev/shm
tmpfs                    3.9G  8.6M  3.9G   1% /run
tmpfs                    3.9G     0  3.9G   0% /sys/fs/cgroup
/dev/sda5                 19G   33M   19G   1% /home
/dev/sda1                497M  119M  379M  24% /boot
tmpfs                    783M     0  783M   0% /run/user/0
/dev/mapper/MySQL-lvol0  499G   44G  456G   9% /data

#lvextend -rl +100%FREE /dev/MySQL/lvol0
  Size of logical volume MySQL/lvol0 changed from <500.00 GiB (127999 extents) to 699.99 GiB (179198 extents).
  Logical volume MySQL/lvol0 successfully resized.
meta-data=/dev/mapper/MySQL-lvol0 isize=256    agcount=4, agsize=32702464 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=0        finobt=0
data     =                       bsize=4096   blocks=130809856, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=0
log      =internal               bsize=4096   blocks=63872, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 130809856 to 183498752

[root@db210_13:49:04 /data]  
#df -h
Filesystem               Size  Used Avail Use% Mounted on
/dev/sda3                 39G   12G   28G  30% /
devtmpfs                 3.9G     0  3.9G   0% /dev
tmpfs                    3.9G     0  3.9G   0% /dev/shm
tmpfs                    3.9G  8.6M  3.9G   1% /run
tmpfs                    3.9G     0  3.9G   0% /sys/fs/cgroup
/dev/sda5                 19G   33M   19G   1% /home
/dev/sda1                497M  119M  379M  24% /boot
tmpfs                    783M     0  783M   0% /run/user/0
/dev/mapper/MySQL-lvol0  700G   44G  657G   7% /data