CentOS7.x系统根目录分区扩容

说明：系统版本为 Linux version 3.10.0-327.el7.x86_64

step1. 查看现有磁盘信息，可以看出根分区有45G

[root@DEV-CMDB-DB02 ~]# df -h
Filesystem                           Size  Used Avail Use% Mounted on
/dev/mapper/centos_mb--centos7-root   45G  .8G   35G  % /
devtmpfs                             .9G       .9G   % /dev
tmpfs                                .9G   84K  .9G   % /dev/shm
tmpfs                                .9G  8.9M  .9G   % /run
tmpfs                                .9G       .9G   % /sys/fs/cgroup
/dev/sda1                            497M  142M  356M  % /boot
tmpfs                                .2G   16K  .2G   % /run/user/
tmpfs                                .2G       .2G   % /run/user/

step2. 查看新增加的磁盘信息

[root@DEV-CMDB-DB02 ~]# fdisk -l

Disk /dev/sda: 53.7 GB,  bytes,  sectors
Units = sectors of  *  =  bytes
Sector size (logical/physical):  bytes /  bytes
I/O size (minimum/optimal):  bytes /  bytes
Disk label type: dos
Disk identifier: 0x000e0945

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *                        Linux
/dev/sda2                   8e  Linux LVM

Disk /dev/sdb: 107.4 GB,  bytes,  sectors
Units = sectors of  *  =  bytes
Sector size (logical/physical):  bytes /  bytes
I/O size (minimum/optimal):  bytes /  bytes

Disk /dev/mapper/centos_mb--centos7-root: 47.7 GB,  bytes,  sectors
Units = sectors of  *  =  bytes
Sector size (logical/physical):  bytes /  bytes
I/O size (minimum/optimal):  bytes /  bytes

Disk /dev/mapper/centos_mb--centos7-swap:  MB,  bytes,  sectors
Units = sectors of  *  =  bytes
Sector size (logical/physical):  bytes /  bytes
I/O size (minimum/optimal):  bytes /  bytes

step3. 根据以上信息，对新增加的磁盘进行分区

[root@DEV-CMDB-DB02 ~]# fdisk /dev/sdb
Welcome to fdisk (util-linux 2.23.).

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 0x232defba.

Command (m for help): p

Disk /dev/sdb: 107.4 GB,  bytes,  sectors
Units = sectors of  *  =  bytes
Sector size (logical/physical):  bytes /  bytes
I/O size (minimum/optimal):  bytes /  bytes
Disk label type: dos
Disk identifier: 0x232defba

   Device Boot      Start         End      Blocks   Id  System

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

Command (m for help): t
Selected partition
Hex code (type L to list all codes): L

   Empty             NEC DOS           Minix / old Lin bf  Solaris
   FAT12             Hidden NTFS Win   Linux swap / So c1  DRDOS/sec (FAT-
   XENIX root        Plan             Linux           c4  DRDOS/sec (FAT-
   XENIX usr       3c  PartitionMagic    OS/ hidden C:  c6  DRDOS/sec (FAT-
   FAT16 <32M        Venix        Linux extended  c7  Syrinx
   Extended          PPC PReP Boot     NTFS volume set da  Non-FS data
   FAT16             SFS               NTFS volume set db  CP/M / CTOS / .
   HPFS/NTFS/exFAT 4d  QNX4.x            Linux plaintext de  Dell Utility
   AIX             4e  QNX4.x 2nd part 8e  Linux LVM       df  BootIt
   AIX bootable    4f  QNX4.x 3rd part   Amoeba          e1  DOS access
 a  OS/ Boot Manag   OnTrack DM        Amoeba BBT      e3  DOS R/O
 b  W95 FAT32         OnTrack DM6 Aux 9f  BSD/OS          e4  SpeedStor
 c  W95 FAT32 (LBA)   CP/M            a0  IBM Thinkpad hi eb  BeOS fs
 e  W95 FAT16 (LBA)   OnTrack DM6 Aux a5  FreeBSD         ee  GPT
 f  W95 Ext'd (LBA) 54  OnTrackDM6      a6  OpenBSD         ef  EFI (FAT-12/16/
  OPUS              EZ-Drive        a7  NeXTSTEP        f0  Linux/PA-RISC b
  Hidden FAT12      Golden Bow      a8  Darwin UFS      f1  SpeedStor
  Compaq diagnost 5c  Priam Edisk     a9  NetBSD          f4  SpeedStor
  Hidden FAT16 <   SpeedStor       ab  Darwin boot     f2  DOS secondary
  Hidden FAT16      GNU HURD or Sys af  HFS / HFS+      fb  VMware VMFS
  Hidden HPFS/NTF   Novell Netware  b7  BSDI fs         fc  VMware VMKCORE
  AST SmartSleep    Novell Netware  b8  BSDI swap       fd  Linux raid auto
1b  Hidden W95 FAT3   DiskSecure Mult bb  Boot Wizard hid fe  LANstep
1c  Hidden W95 FAT3   PC/IX           be  Solaris boot    ff  BBT
1e  Hidden W95 FAT1   Old Minix
Hex code (type L to list all codes): 8e
Changed type of partition 'Linux' to 'Linux LVM'

Command (m for help): p

Disk /dev/sdb: 107.4 GB,  bytes,  sectors
Units = sectors of  *  =  bytes
Sector size (logical/physical):  bytes /  bytes
I/O size (minimum/optimal):  bytes /  bytes
Disk label type: dos
Disk identifier: 0x232defba

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1                     8e  Linux LVM

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

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

step4. 创建物理卷

[root@DEV-CMDB-DB02 ~]# pvcreate /dev/sdb1
  Physical volume "/dev/sdb1" successfully created

step5. 查看物理卷信息

[root@DEV-CMDB-DB02 ~]# pvdisplay
  --- Physical volume ---
  PV Name               /dev/sda2
  VG Name               centos_mb-centos7
  PV Size               49.51 GiB / not usable 3.00 MiB
  Allocatable           yes
  PE Size               4.00 MiB
  Total PE
  Free PE
  Allocated PE
  PV UUID               8WbgjB-T1Lf-kqUD-qPFw-UwJu-B9Lc-GAUTUB

  "/dev/sdb1" is a new physical volume of "100.00 GiB"
  --- NEW Physical volume ---
  PV Name               /dev/sdb1
  VG Name
  PV Size               100.00 GiB
  Allocatable           NO
  PE Size
  Total PE
  Free PE
  Allocated PE
  PV UUID               HOknRs-TnMy-wtfX-sGqD-5RK9-dk9q-ze13fj

[root@DEV-CMDB-DB02 ~]# vgdisplay
  --- Volume group ---
  VG Name               centos_mb-centos7
  System ID
  Format                lvm2
  Metadata Areas
  Metadata Sequence No
  VG Access             read/write
  VG Status             resizable
  MAX LV
  Cur LV
  Open LV
  Max PV
  Cur PV
  Act PV
  VG Size               49.51 GiB
  PE Size               4.00 MiB
  Total PE
  Alloc PE / Size        / 49.47 GiB
  Free  PE / Size        / 40.00 MiB
  VG UUID               aN2D2P-Rk1y-wGFz-5l2I-5CcD-7s88-Z8czc7

step6. 将新增加的分区/dev/sdb1加入到根目录分区centos_mb-centos7中

[root@DEV-CMDB-DB02 ~]# vgextend centos_mb-centos7 /dev/sdb1
  Volume group "centos_mb-centos7" successfully extended

step7. 重新查看卷组信息

[root@DEV-CMDB-DB02 ~]# vgdisplay
  --- Volume group ---
  VG Name               centos_mb-centos7
  System ID
  Format                lvm2
  Metadata Areas
  Metadata Sequence No
  VG Access             read/write
  VG Status             resizable
  MAX LV
  Cur LV
  Open LV
  Max PV
  Cur PV
  Act PV
  VG Size               149.50 GiB
  PE Size               4.00 MiB
  Total PE
  Alloc PE / Size        / 49.47 GiB
  Free  PE / Size       25609 / 100.04 GiB
  VG UUID               aN2D2P-Rk1y-wGFz-5l2I-5CcD-7s88-Z8czc7

step9. 进行卷扩容

[root@DEV-CMDB-DB02 ~]# lvextend -l +%FREE /dev/mapper/centos_mb--centos7-root
  Size of logical volume centos_mb-centos7/root changed from 44.47 GiB ( extents) to 144.50 GiB ( extents).
  Logical volume root successfully resized.

step10. 调整卷分区大小

[root@DEV-CMDB-DB02 ~]# xfs_growfs /dev/mapper/centos_mb--centos7-root
meta-data=/dev/mapper/centos_mb--centos7-root isize=    agcount=, agsize= blks
         =                       sectsz=   attr=, projid32bit=
         =                       crc=        finobt=
data     =                       bsize=   blocks=, imaxpct=
         =                       sunit=      swidth= blks
naming   =version               bsize=   ascii-ci= ftype=
log      =internal               bsize=   blocks=, version=
         =                       sectsz=   sunit= blks, lazy-count=
realtime =none                   extsz=   blocks=, rtextents=
data blocks changed from  to 

最后，查看磁盘信息可以看出根目录分区大小已成功扩容

[root@DEV-CMDB-DB02 ~]# df -h
Filesystem                           Size  Used Avail Use% Mounted on
/dev/mapper/centos_mb--centos7-root  145G  .8G  135G   % /
devtmpfs                             .9G       .9G   % /dev
tmpfs                                .9G   84K  .9G   % /dev/shm
tmpfs                                .9G  8.9M  .9G   % /run
tmpfs                                .9G       .9G   % /sys/fs/cgroup
/dev/sda1                            497M  142M  356M  % /boot
tmpfs                                .2G   16K  .2G   % /run/user/
tmpfs                                .2G       .2G   % /run/user/