怎样给centos系统扩展磁盘分区的实现方法

  root@eve-ng:~# df -h  Filesystem          Size Used Avail Use% Mounted on  udev             7.9G   0 7.9G  0% /dev  tmpfs             1.6G  19M 1.6G  2% /run  /dev/mapper/eve--ng--vg-root  38G  13G  23G 36% /  tmpfs             7.9G   0 7.9G  0% /dev/shm  tmpfs             5.0M   0 5.0M  0% /run/lock  tmpfs             7.9G   0 7.9G  0% /sys/fs/cgroup  /dev/sda1           472M  83M 365M 19% /boot    root@eve-ng:~# fdisk -l  ...省略部分内容  Disk /dev/sda: 250 GiB, 268435456000 bytes, 524288000 sectors  //可以看到已经有250G了  Units: sectors of 1 * 512 = 512 bytes  Sector size (logical/physical): 512 bytes / 512 bytes  I/O size (minimum/optimal): 512 bytes / 512 bytes  Disklabel type: dos  Disk identifier: 0x3e3ca055    Device   Boot  Start   End Sectors Size Id Type  /dev/sda1 *    2048  999423  997376 487M 83 Linux  /dev/sda2    1001470 83884031 82882562 39.5G 5 Extended  /dev/sda5    1001472 83884031 82882560 39.5G 8e Linux LVM    Disk /dev/mapper/eve--ng--vg-root: 38.6 GiB, 41406169088 bytes, 80871424 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/eve--ng--vg-swap_1: 980 MiB, 1027604480 bytes, 2007040 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    //下面执行分区  root@eve-ng:~# fdisk /dev/sda    Welcome to fdisk (util-linux 2.27.1).  Changes will remain in memory only, until you decide to write them.  Be careful before using the write command.    Command (m for help): n  Partition type    p  primary (1 primary, 1 extended, 2 free)    l  logical (numbered from 5)  Select (default p): p  Partition number (3,4, default 3): 3  First sector (999424-524287999, default 999424): 83884032 //注意，这里是之前分配的最后一块（sda5 end）加一（83884031+1）  Last sector, +sectors or +size{K,M,G,T,P} (83884032-524287999, default 524287999): //注意看这是不是最后一块    Created a new partition 3 of type 'Linux' and of size 210 GiB.    Command (m for help): t  Partition number (1-3,5, default 5): 3 3  Partition type (type L to list all types): 8e    Changed type of partition 'Linux' to 'Linux LVM'.    Command (m for help): w  The partition table has been altered.  Calling ioctl() to re-read partition table.  Re-reading the partition table failed.: Device or resource busy    The kernel still uses the old table. The new table will be used at the next reboot or after you run partprobe(8) or kpartx(8).    root@eve-ng:~# reboot    root@eve-ng:~# pvcreate /dev/sda3   Physical volume "/dev/sda3" successfully created  root@eve-ng:~# vgdisplay   --- Volume group ---   VG Name        eve-ng-vg   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        39.52 GiB   PE Size        4.00 MiB   Total PE       10117   Alloc PE / Size    10117 / 39.52 GiB   Free PE / Size    0 / 0   VG UUID        EvwUbc-nfsg-dHqA-znxB-U3gv-V782-Q8ZxkI    root@eve-ng:~# vgextend eve-ng-vg /dev/sda3   Volume group "eve-ng-vg" successfully extended  root@eve-ng:~# vgdisplay   --- Volume group ---   VG Name        eve-ng-vg   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        249.52 GiB   PE Size        4.00 MiB   Total PE       63877   Alloc PE / Size    10117 / 39.52 GiB   Free PE / Size    53760 / 210.00 GiB   VG UUID        EvwUbc-nfsg-dHqA-znxB-U3gv-V782-Q8ZxkI    root@eve-ng:~# lvdisplay   --- Logical volume ---   LV Path        /dev/eve-ng-vg/root   LV Name        root   VG Name        eve-ng-vg   LV UUID        ktUpR0-VpqS-rJJv-a1FC-u6Gd-U8yN-2WYQ53   LV Write Access    read/write   LV Creation host, time eve-ng, 2018-03-21 02:25:21 +0200   LV Status       available   # open         1   LV Size        38.56 GiB   Current LE       9872   Segments        1   Allocation       inherit   Read ahead sectors   auto   - currently set to   256   Block device      253:0    //扩展逻辑卷  root@eve-ng:~# lvextend -l +100%FREE /dev/eve-ng-vg/root   Size of logical volume eve-ng-vg/root changed from 38.56 GiB (9872 extents) to 248.56 GiB (63632 extents).   Logical volume root successfully resized.    root@eve-ng:~# df -h  Filesystem          Size Used Avail Use% Mounted on  udev             7.9G   0 7.9G  0% /dev  tmpfs             1.6G  19M 1.6G  2% /run  /dev/mapper/eve--ng--vg-root  38G  13G  23G 36% /  tmpfs             7.9G   0 7.9G  0% /dev/shm  tmpfs             5.0M   0 5.0M  0% /run/lock  tmpfs             7.9G   0 7.9G  0% /sys/fs/cgroup  /dev/sda1           472M  83M 365M 19% /boot    //在线扩容,要先查看当前的文件系统的类型，可以通过cat /etc/fstab来查看  root@eve-ng:~# resize2fs /dev/eve-ng-vg/root  resize2fs 1.42.13 (17-May-2015)  Filesystem at /dev/eve-ng-vg/root is mounted on /; on-line resizing required  old_desc_blocks = 3, new_desc_blocks = 16  The filesystem on /dev/eve-ng-vg/root is now 65159168 (4k) blocks long.    root@eve-ng:~# df -h  Filesystem          Size Used Avail Use% Mounted on  udev             7.9G   0 7.9G  0% /dev  tmpfs             1.6G  19M 1.6G  2% /run  /dev/mapper/eve--ng--vg-root 245G  13G 222G  6% /  tmpfs             7.9G   0 7.9G  0% /dev/shm  tmpfs             5.0M   0 5.0M  0% /run/lock  tmpfs             7.9G   0 7.9G  0% /sys/fs/cgroup  /dev/sda1           472M  83M 365M 19% /boot