Vm虚拟机下Linux扩展原有磁盘空间，10G
10G的基础上不能满足需求，只好进行磁盘扩展。
调整到合适的磁盘空间
需注意以下几点： linux只能扩展磁盘容量而不能减小， 所填写的容量为总容量，即包含已分区的磁盘。
- 启动虚假机，查看磁盘分区
[root@node1 ~]# fdisk -l
总磁盘大小32.2GB,其中磁盘分了sda1,sda2两个分区。Linux LVM为虚拟机分区约有9GB磁盘空间。
- 创建新分区
[root@node1 ~]# fdisk /dev/sda #输入m查看帮助文档 Command (m for help): m Command action a toggle a bootable flag b edit bsd disklabel c toggle the dos compatibility flag d delete a partition g create a new empty GPT partition table G create an IRIX (SGI) partition table l list known partition types m print this menu n add a new partition #创建新分区 o create a new empty DOS partition table p print the partition table q quit without saving changes s create a new empty Sun disklabel t change a partition's system id u change display/entry units v verify the partition table w write table to disk and exit x extra functionality (experts only)
3.执行分区创建
Command (m for help): n
Partition type:
p primary (2 primary, 0 extended, 2 free) #创建主分区
e extended #创建扩展分区
Select (default p): p
Partition number (3,4, default 3): #由前面已有2个分区，所有从3开始
First sector (20971520-62914559, default 20971520): #一路回车即可
Using default value 20971520
Last sector, +sectors or +size{K,M,G} (20971520-62914559, default 62914559):
Using default value 62914559
Partition 3 of type Linux and of size 20 GiB is set
Command (m for help): w #保存退出
The partition table has been altered!
4.重新查看分区
我们的新建分区/dev/sda3
[root@node1 ~]# fdisk -l Disk /dev/sda: 32.2 GB, 32212254720 bytes, 62914560 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: 0x00009cb6 Device Boot Start End Blocks Id System /dev/sda1 * 2048 2099199 1048576 83 Linux /dev/sda2 2099200 20971519 9436160 8e Linux LVM #sda3为新创建的分区 /dev/sda3 20971520 62914559 20971520 83 Linux Disk /dev/mapper/centos-root: 8585 MB, 8585740288 bytes, 16769024 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/mapper/centos-swap: 1073 MB, 1073741824 bytes, 2097152 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
4.查看文件系统格式、分区格式化
#查看文件系统格式 df -T -h #分区格式化 mkfs.xfs /dev/sda3 #格式化为xfs格式
#进入lvm管理 lvm lvm> pvcreate /dev/sda3 #这是初始化刚才的分区3 WARNING: ext4 signature detected on /dev/sda3 at offset 1080. Wipe it? [y/n]: y Wiping ext4 signature on /dev/sda3. Physical volume "/dev/sda3" successfully created. lvm> vgdisplay -v #卷和卷组的命令可以通过 vgdisplay查看 --- Volume group --- VG Name centos System ID Format lvm2 metadata Areas 1 metadata Sequence No 3 VG Access read/write VG Status resizable MAX LV 0 Cur LV 2 Open LV 2 Max PV 0 Cur PV 1 Act PV 1 VG Size <9.00 GiB PE Size 4.00 MiB Total PE 2303 Alloc PE / Size 2303 / <9.00 GiB Free PE / Size 0 / 0 VG UUID zy2221-18Zz-hNix-Xa40-fn2S-ymfs-QfifRi --- Logical volume --- LV Path /dev/centos/swap LV Name swap VG Name centos LV UUID ypW1dW-fdTc-qCso-7Wck-L1gH-hsOp-v4ZBey LV Write Access read/write LV Creation host, time localhost, 2021-06-25 13:10:00 +0800 LV Status available # open 2 LV Size 1.00 GiB Current LE 256 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 253:1 --- Logical volume --- LV Path /dev/centos/root LV Name root VG Name centos LV UUID 2IDcZo-HeDY-VzTg-FIAP-YhvQ-qU0K-cxyuBr LV Write Access read/write LV Creation host, time localhost, 2021-06-25 13:10:00 +0800 LV Status available # open 1 LV Size <8.00 GiB Current LE 2047 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 253:0 --- Physical volumes --- PV Name /dev/sda2 PV UUID kb7rhp-Lcow-6z3W-RBYx-fJxo-pHUc-cLxYTN PV Status allocatable Total PE / Free PE 2303 / 0 lvm> vgextend centos /dev/sda3 #将初始化过的分区加入到虚拟卷组centos Volume group "centos" successfully extended
可以查看到新加入的物理卷sda3
通过vgdisplay再次查看，可以发现Volume group中多了Free PE / Size 5119 / <20.00 GiB一行记录
lvm> vgdisplay -v --- Volume group --- VG Name centos System ID Format lvm2 metadata Areas 2 metadata Sequence No 4 VG Access read/write VG Status resizable MAX LV 0 Cur LV 2 Open LV 2 Max PV 0 Cur PV 2 Act PV 2 VG Size 28.99 GiB PE Size 4.00 MiB Total PE 7422 Alloc PE / Size 2303 / <9.00 GiB Free PE / Size 5119 / <20.00 GiB VG UUID zy2221-18Zz-hNix-Xa40-fn2S-ymfs-QfifRi --- Logical volume --- LV Path /dev/centos/swap LV Name swap VG Name centos LV UUID ypW1dW-fdTc-qCso-7Wck-L1gH-hsOp-v4ZBey LV Write Access read/write LV Creation host, time localhost, 2021-06-25 13:10:00 +0800 LV Status available # open 2 LV Size 1.00 GiB Current LE 256 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 253:1 --- Logical volume --- LV Path /dev/centos/root LV Name root VG Name centos LV UUID 2IDcZo-HeDY-VzTg-FIAP-YhvQ-qU0K-cxyuBr LV Write Access read/write LV Creation host, time localhost, 2021-06-25 13:10:00 +0800 LV Status available # open 1 LV Size <8.00 GiB Current LE 2047 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 253:0 --- Physical volumes --- PV Name /dev/sda2 PV UUID kb7rhp-Lcow-6z3W-RBYx-fJxo-pHUc-cLxYTN PV Status allocatable Total PE / Free PE 2303 / 0 PV Name /dev/sda3 PV UUID V708hY-OO5p-IH3v-ZRlU-Torj-tXOC-ERvLr1 PV Status allocatable Total PE / Free PE 5119 / 5119 #/dev/mapper/centos-root 为根路径挂载点 lvm> lvextend -l+5119 /dev/mapper/centos-root ##扩展已有卷的容量（5119 是通过vgdisplay查看Free PE / Size的大小） Size of logical volume centos/root changed from <8.00 GiB (2047 extents) to 27.99 GiB (7166 extents). Logical volume centos/root successfully resized. lvm> pvdisplay --- Physical volume --- PV Name /dev/sda2 VG Name centos PV Size <9.00 GiB / not usable 3.00 MiB Allocatable yes (but full) PE Size 4.00 MiB Total PE 2303 Free PE 0 Allocated PE 2303 PV UUID kb7rhp-Lcow-6z3W-RBYx-fJxo-pHUc-cLxYTN --- Physical volume --- PV Name /dev/sda3 VG Name centos PV Size 20.00 GiB / not usable 4.00 MiB Allocatable yes (but full) PE Size 4.00 MiB Total PE 5119 Free PE 0 Allocated PE 5119 PV UUID V708hY-OO5p-IH3v-ZRlU-Torj-tXOC-ERvLr1 lvm>quit #退出3.文件系统的扩容
以上只是做成了卷扩容，接下来做文件系统的真正扩容
#执行df -h时根目录的挂载点 df -h
centos7执行执行扩容
xfs_growfs /dev/mapper/centos-root
再次查看磁盘使用情况
df -h
可以看见根目录下的磁盘空间已经扩展为28G了
