一.環境資訊
  OS：CentOS 6.6
  mysql ：mariadb 10.0.20

二.環境準備

先安裝xfs相關的包：
yum install xfs*
300G盤建立pv:
pvcreate /dev/sdc
  Physical volume "/dev/sdc" successfully created
建立vg:
vgcreate vgdata /dev/sdc
 Volume group "vgdata" successfully created
建立lv:
 lvcreate -L 299G -n lvdata vgdata
 Logical volume "lvdata" created

建立xfs檔案系統：
mkfs.xfs -f -i attr=2 -l lazy-count=1,sectsize=4096 -b size=4096 -d sectsize=4096 -L data /dev/vgdata/lvdata
臨時掛載：
mkdir -p /datatemp
mount -o rw,noatime,nodiratime,noikeep,nobarrier,allocsize=100M,attr2,largeio,inode64,swalloc /dev/vgdata/lvdata /datatemp
停掉mysql:
/apps/svr/mariadb10/bin/mysqladmin  -uroot -p -S /tmp/mysql3306.sock shutdown
先將原盤資料copy到新盤上:
cd /data
cp -p -r * /datatemp/
umount檔案系統：
umount /data
umount /datatemp
mount新盤：
mount -o rw,noatime,nodiratime,noikeep,nobarrier,allocsize=100M,attr2,largeio,inode64,swalloc /dev/vgdata/lvdata /data
啟動mysql:
 /apps/svr/mariadb10/bin/mysqld_safe --defaults-file=/apps/dbdat/my3306.cnf &
檢視vg:
[

[email protected] data]# vgs
  VG      #PV #LV #SN Attr   VSize   VFree  
  vg_root   1   2   0 wz--n-  39.80g       0
  vgapp     1   1   0 wz--n- 200.00g    5.00g
  vgdata    1   1   0 wz--n- 300.00g 1020.00m
刪除原VG:
[[email protected] data]# vgremove vgapp
Do you really want to remove volume group "vgapp" containing 1 logical volumes? [y/n]: y
Do you really want to remove active logical volume lvapp? [y/n]: y
  Logical volume "lvapp" successfully removed
  Volume group "vgapp" successfully removed

檢視pv:
[[email protected] data]# pvs
  PV         VG      Fmt  Attr PSize   PFree  
  /dev/sda2  vg_root lvm2 a--   39.80g       0
  /dev/sdb1          lvm2 ---  200.00g  200.00g
  /dev/sdc   vgdata  lvm2 a--  300.00g 1020.00m

三.線上擴容

現在是需要將/dev/sdb1線上加到vgdata中，並在線擴容xfs檔案系統/dev/vgdata/lvdata，現在才到正題，前面是準備環境。

將/dev/sdb1加到vgdata:
vgextend vgdata /dev/sdb1

Volume group "vgdata" successfully extended

[[email protected] data]# vgs
  VG      #PV #LV #SN Attr   VSize   VFree 
  vg_root   1   2   0 wz--n-  39.80g      0
  vgdata    2   1   0 wz--n- 499.99g 200.99g

[[email protected] data]# lvs
  LV       VG      Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  LogVol01 vg_root -wi-ao----  35.80g                                                   
  lv_swap  vg_root -wi-ao----   4.00g                                                   
  lvdata   vgdata  -wi-ao---- 299.00g 

lv擴充套件：
lvextend -L 499G /dev/vgdata/lvdata (若+10G，用-L +10G來表示)

Size of logical volume vgdata/lvdata changed from 299.00 GiB (76544 extents) to 499.00 GiB (127744 extents).
  Logical volume lvdata successfully resized
[[email protected] data]# lvs
  LV       VG      Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  LogVol01 vg_root -wi-ao----  35.80g                                                   
  lv_swap  vg_root -wi-ao----   4.00g                                                   
  lvdata   vgdata  -wi-ao---- 499.00g                                                   
[[email protected] data]# vgs
  VG      #PV #LV #SN Attr   VSize   VFree  
  vg_root   1   2   0 wz--n-  39.80g       0
  vgdata    2   1   0 wz--n- 499.99g 1016.00m

xfs檢視：
xfs_info /dev/vgdata/lvdata
[[email protected] data]# xfs_info /dev/vgdata/lvdata
meta-data=/dev/mapper/vgdata-lvdata isize=256    agcount=4, agsize=19595264 blks
         =                       sectsz=4096  attr=2, projid32bit=0
data     =                       bsize=4096   blocks=78381056, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0
log      =internal               bsize=4096   blocks=38272, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

xfs擴充套件：

擴充套件前：
/dev/mapper/vgdata-lvdata 299G   36G  264G  12% /data

xfs_growfs /dev/vgdata/lvdata  ---若加-D 引數可以指定擴大到多少，不加直接加到最大空間
[[email protected] data]# xfs_growfs /dev/vgdata/lvdata
meta-data=/dev/mapper/vgdata-lvdata isize=256    agcount=4, agsize=19595264 blks
         =                       sectsz=4096  attr=2, projid32bit=0
data     =                       bsize=4096   blocks=78381056, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0
log      =internal               bsize=4096   blocks=38272, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 78381056 to 130809856
擴充套件後：
/dev/mapper/vgdata-lvdata 499G   36G  464G   8% /data

四.檢查mysql是否正常

檢查程序：
[[email protected] data]# ps -ef|grep mysql
apps     25359     1  0 14:21 pts/0    00:00:00 /bin/sh /apps/svr/mariadb10/bin/mysqld_safe --defaults-file=/apps/dbdat/my3306.cnf
apps     25915 25359  0 14:21 pts/0    00:00:03 /apps/svr/mariadb10/bin/mysqld --defaults-file=/apps/dbdat/my3306.cnf --basedir=/apps/svr/mariadb10 --datadir=/apps/dbdat/mariadb10_data3306 --plugin-dir=/apps/svr/mariadb10/lib/plugin --log-error=/apps/logs/mysql/error3306.log --open-files-limit=8192 --pid-file=/apps/dbdat/mariadb10_data3306/mysql.pid --socket=/tmp/mysql3306.sock --port=3306
root     26402 25101  0 14:55 pts/0    00:00:00 grep mysql
檢查埠:
[[email protected] data]# netstat -an|grep 3306
tcp        0      0 0.0.0.0:3306                0.0.0.0:*                   LISTEN     
unix  2      [ ACC ]     STREAM     LISTENING     15455908 /tmp/mysql3306.sock
 
mysql表查詢操作正常。