centos根分区大小增加

第一步
添加第二块硬盘sdb进行分区
[root@linuxidc ~]# fdisk /dev/sdb
n+P+4+空格+w
说明：上面操作对sdb硬盘进行了分区操作，设为sdb4分区了（当然上面建立的主分区可以为1-4中的任意一个，我这里选择的4）。
 第二步、对新建立的sdb4分区进行格式
[root@linuxidc ~]# mkfs.ext4 /dev/sdb4
mke2fs 1.41.12 (17-May-2010)
文件系统标签=
操作系统:Linux
块大小=4096 (log=2)
分块大小=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
1048576 inodes, 4192957 blocks
209647 blocks (5.00%) reserved for thesuper user
第一个数据块=0
Maximum filesystem blocks=4294967296
128 block groups
32768 blocks per group, 32768 fragments pergroup
8192 inodes per group
Superblock backups stored on blocks:
 32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
 4096000
 正在写入inode表: 完成
Creating journal (32768 blocks): 完成
Writing superblocks and filesystemaccounting information: done完成
 This filesystem will be automaticallychecked every 20 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
 说明：将sdb4分区格式化为ext4格式，因为CentOS安装是系统的格式ext4，所以这里要注意一下。
 第三步、格式后的sdb4分区添加为物理卷
[root@linuxidc ~]# pvcreate /dev/sdb4
Physical volume "/dev/sdb4" successfully created
第四步、查看当前系统的物理卷（PV）情况
 [root@linuxidc ~]# pvdisplay
---Physical volume ---
PVName /dev/sda2
VGName VolGroup
PVSize 15.51 GiB / not usable3.00 MiB
Allocatable yes (butfull)
PESize 4.00 MiB
Total PE 3970
Free PE 0
Allocated PE 3970
PVUUID Up77sG-sNKf-Ja0k-crBf-N0wz-a5hy-T6sVFh
 "/dev/sdb4" is a new physical volume of "15.99 GiB"
---NEW Physical volume ---
PVName /dev/sdb4
VGName
PVSize 15.99 GiB
Allocatable NO
PESize 0
Total PE 0
Free PE 0
Allocated PE 0
PVUUID Gqnw7N-HooX-S2Nz-1NIZ-YpOe-g0jo-grG1rQ
说明：可以看到添加的新物理卷sdb4，大小都符合我们添加时的设置
 第五步、查看当前卷组情况
[root@linuxidc ~]# vgdisplay
---Volume group ---
VGName VolGroup
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 3
VGAccess read/write
VGStatus resizable
MAXLV 0
CurLV 2
Open LV 2
MaxPV 0
CurPV 1
ActPV 1
VGSize 15.51 GiB
PESize 4.00 MiB
Total PE 3970
Alloc PE / Size 3970 / 15.51GiB
Free PE / Size 0 / 0
VGUUID PPrifh-glzl-nnxX-YkBm-xJ1s-rgnw-d1WsJd
 第六步、将分区sdb4转换为扩展分区
 [root@linuxidc ~]# vgextend VolGroup/dev/sdb4
Volume group "VolGroup" successfully extended
 第七步、查看当前的逻辑卷
 [root@linuxidc ~]# lvdisplay
---Logical volume ---
LVPath /dev/VolGroup/lv_root
LVName lv_root
VGName VolGroup
LVUUID dCIsej-0NWX-bVFe-bT6L-c4eY-oy4G-9lNBOC
LVWrite Access read/write
LVCreation host, time ,
LVStatus available
#open 1
LVSize 7.75 GiB
Current LE 1985
Segments 1
Allocation inherit
Read ahead sectors auto
-currently set to 256
Block device 253:0
 ---Logical volume ---
LVPath /dev/VolGroup/lv_swap
LVName lv_swap
VGName VolGroup
LVUUID K5bxJo-2SmM-6NCU-mBJP-Qzp1-ZODH-nbLK0k
LVWrite Access read/write
LVCreation host, time ,
LVStatus available
#open 1
LVSize 7.75 GiB
Current LE 1985
Segments 1
Allocation inherit
Read ahead sectors auto
-currently set to 256
Block device 253:1
 说明：这里可以看到“/”根分区的路径名称为：/dev/VolGroup/lv_root
 第八步、查看扩展后的卷组情况
[root@linuxidc ~]# vgdisplay
---Volume group ---
VGName VolGroup
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 4
VGAccess read/write
VGStatus resizable
MAXLV 0
CurLV 2
Open LV 2
MaxPV 0
CurPV 2
ActPV 2
VGSize 31.50 GiB
PESize 4.00 MiB
Total PE 8064
Alloc PE / Size 3970 / 15.51GiB
Free PE / Size 4094 / 15.99 GiB
VGUUID PPrifh-glzl-nnxX-YkBm-xJ1s-rgnw-d1WsJd
说明：扩展后的卷子情况
 第九步、将新增的逻辑卷全部扩展到“/”分区中
扩展逻辑卷LogVol00的容量(根目录"/"的挂载点)
lvextend -L +1024M /dev/VolGroup00/LogVol00
/sbin/resize2fs /dev/VolGroup00/LogVol00
说明：-L 添加所需大小，resize2fs刷新根分区大小