最近在VMware虚拟机上使用Centos，用着用着，发现虚拟机的磁盘空间不够了。通过以下步骤成功扩展了根目录的磁盘空间
1、Centos 关机，选择编辑虚拟机设置，硬盘，在实用工具那里选择“扩展”
填写扩展的磁盘容量
点击扩展后，VMware会提示磁盘已成功扩展。您必须从客户机操作系统内部对磁盘重新进行分区和扩展文件系统。也就是说，这里扩展的磁盘空间，在操作系统里面还不可用，还没生效，需要在操作系统里面进行设置后才能使用。
2、启动客户机操作系统Centos，查看磁盘情况
输入指令
fdisk -l
显示结果如下
[root@localhost ~]# fdisk -lDisk /dev/sda: 75.2 GB, 75161927680 bytes, 146800640 sectorsUnits = sectors of 1 * 512 = 512 bytesSector size (logical/physical): 512 bytes / 512 bytesI/O size (minimum/optimal): 512 bytes / 512 bytesDisk label type: dosDisk identifier: 0x000ab772Device BootStart EndBlocks Id System/dev/sda1 * 204820991991048576 83 Linux/dev/sda2 2099200 41943039 19921920 8e Linux LVMDisk /dev/mapper/centos-root: 18.2 GB, 18249416704 bytes, 35643392 sectorsUnits = sectors of 1 * 512 = 512 bytesSector size (logical/physical): 512 bytes / 512 bytesI/O size (minimum/optimal): 512 bytes / 512 bytesDisk /dev/mapper/centos-swap: 2147 MB, 2147483648 bytes, 4194304 sectorsUnits = sectors of 1 * 512 = 512 bytesSector size (logical/physical): 512 bytes / 512 bytesI/O size (minimum/optimal): 512 bytes / 512 bytes[root@localhost ~]# fdisk /dev/sdaWelcome 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 mand (m for help): n # 输入 n 进入Partition type:p primary (2 primary, 0 extended, 2 free)e extendedSelect (default p): p # 输入 p 进行扩容模式Partition number (3,4, default 3): 3# 输入 3 因为前面已经有两个了First sector (41943040-146800639, default 41943040):Using default value 41943040Last sector, +sectors or +size{K,M,G} (41943040-146800639, default 146800639):Using default value 146800639Partition 3 of type Linux and of size 50 GiB is setCommand (m for help): w # 输入 w 保存退出The partition table has been altered!Calling ioctl() to re-read partition table.WARNING: Re-reading the partition table failed with error 16: Device or resource busy.The kernel still uses the old table. The new table will be used atthe next reboot or after you run partprobe(8) or kpartx(8)Syncing disks.
再次查看分区情况
fdisk -l
这时可以看到
Disk /dev/sda: 75.2 GB, 75161927680 bytes, 146800640 sectorsUnits = sectors of 1 * 512 = 512 bytesSector size (logical/physical): 512 bytes / 512 bytesI/O size (minimum/optimal): 512 bytes / 512 bytesDisk label type: dosDisk identifier: 0x000ab772Device BootStart EndBlocks Id System/dev/sda1 * 204820991991048576 83 Linux/dev/sda2 2099200 41943039 19921920 8e Linux LVM/dev/sda3 41943040 146800639 52428800 83 LinuxDisk /dev/mapper/centos-root: 18.2 GB, 18249416704 bytes, 35643392 sectorsUnits = sectors of 1 * 512 = 512 bytesSector size (logical/physical): 512 bytes / 512 bytesI/O size (minimum/optimal): 512 bytes / 512 bytesDisk /dev/mapper/centos-swap: 2147 MB, 2147483648 bytes, 4194304 sectorsUnits = sectors of 1 * 512 = 512 bytesSector size (logical/physical): 512 bytes / 512 bytesI/O size (minimum/optimal): 512 bytes / 512 bytes
其中，分区已变为3个了，但这时还没挂载，还不能用
Device BootStart EndBlocks Id System/dev/sda1 * 204820991991048576 83 Linux/dev/sda2 2099200 41943039 19921920 8e Linux LVM/dev/sda3 41943040 146800639 52428800 83 Linux
3、重启操作系统
reboot
4、查看文件系统格式
输入指令
[root@localhost ~]# blkid
结果为 xfs格式文件系统：
/dev/sda1: UUID="b82649ca-dbc6-4ad7-8757-b8ac8506f1e6" TYPE="xfs"/dev/sda2: UUID="r7VR1e-fCbC-as1M-KAEz-Nf9S-LuLP-yVYwmf" TYPE="LVM2_member"/dev/sr0: UUID="-11-25-23-54-16-00" LABEL="CentOS 7 x86_64" TYPE="iso9660" PTTYPE="dos"/dev/mapper/centos-root: UUID="3808fa57-2fed-4fc0-a04b-63d976d602d9" TYPE="xfs"/dev/mapper/centos-swap: UUID="607a6401-d2f3-4417-835f-730ec0c7e22b" TYPE="swap"
5、将物理硬盘分区初始化为物理卷，以便被LVM使用，输入指令
lvspvcreate /dev/sda3
6、新分区加入物理卷组，更改逻辑卷大小，扩容xfs文件系统
查看lvm组名，输入指令df -h
[root@test001 ~]# df -hFilesystem Size Used Avail Use% Mounted on/dev/mapper/centos-root8.3G 5.4G 2.5G 69% /tmpfs1001M0 1001M 0% /dev/shm/dev/sda1 477M 54M 394M 12% /boot
其中，centos 就是 根 所在的组名
输入指令，增加卷组的容量
vgextend centos /dev/sda3
7、查看可扩展的空间大小
输入指令，显示LNM卷组的元数据信息
vgdisplay
结果为
--- Volume group ---VG NamecentosSystem IDFormatlvm2Metadata Areas 2Metadata Sequence No 4VG Access read/writeVG Status resizableMAX LV0Cur LV2Open LV2Max PV0Cur PV2Act PV2VG Size68.99 GiBPE Size4.00 MiBTotal PE 17662Alloc PE / Size 4863 / <19.00 GiBFree PE / Size 12799 / <50.00 GiBVG UUIDZu3nec-EiMo-dafs-UG3R-RGO0-5qvk-qvqCp9
其中 Free PE / Size 就是可供分配的自由空间，最多有 50G，在扩展时输入小于该值
8、检查下文件系统的正确性
输入：
[root@ucx-auto dev]# e2fsck -f /dev/mapper/centos-root
结果为：
e2fsck 1.42.9 (28-Dec-)/dev/mapper/centos-root is mounted.e2fsck: Cannot continue, aborting.
9、.重新定义大小
[root@localhost ~]# lvextend -L+49.99G /dev/mapper/centos-root /dev/sda3
10、扩容xfs文件系统
[root@ucx-auto dev]# xfs_growfs /dev/mapper/centos-root
结果为：
meta-data=/dev/mapper/centos-root isize=512 agcount=4, agsize=1113856 blks= sectsz=512 attr=2, projid32bit=1= crc=1 finobt=0 spinodes=0data= bsize=4096 blocks=4455424, imaxpct=25= sunit=0swidth=0 blksnaming =version 2 bsize=4096 ascii-ci=0 ftype=1log=internalbsize=4096 blocks=2560, version=2= sectsz=512 sunit=0 blks, lazy-count=1realtime =none extsz=4096 blocks=0, rtextents=0data blocks changed from 4455424 to 17560576
11、最后输入
[root@ucx-auto dev]# df -lh
看到根目录已经扩大了
FilesystemSize Used Avail Use% Mounted on/dev/mapper/centos-root 67G 2.4G 65G 4% /devtmpfs 475M0 475M 0% /devtmpfs487M0 487M 0% /dev/shmtmpfs487M 7.7M 479M 2% /runtmpfs487M0 487M 0% /sys/fs/cgroup/dev/sda11014M 133M 882M 14% /boottmpfs 98M0 98M 0% /run/user/0
