resize2fs 功能说明：调整ext2/ext3/ext4文件系统大小 resize2fs命令用于扩容或收缩未挂载的ext2/ext3/ext4文件系统。 在Linux2.6或更高版本的内核中，该命令还支持在线扩容已经挂载的文件系统，该命令常用来针对LVM扩容后的分区使用。 参数选项： -p 打印完成任务的进度条 -f 强制执行操作 范例：动态修改分区大小的例子 假设是要对/dev/sdb上的分区进行操作，将/mnt/data1扩容。 [root@cs6 ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_cs6-lv_root 26G 834M 24G 4% / tmpfs 931M 0 931M 0% /dev/shm /dev/sda1 477M 28M 424M 7% /boot /dev/sdb1 194M 1.8M 182M 1% /mnt/data1 /dev/sdb2 194M 1.8M 182M 1% /mnt/data2 [root@cs6 ~]# touch /mnt/data1/{1..5}.html [root@cs6 ~]# touch /mnt/data2/{1..5}.html 提示：/dev/sdb是一块1GB的磁盘，现在分了两个主分区sdb1、sdb2，分别是200MB，剩余800MB未分区。现在需要把sdb2分区和sdb1分区合并，以实现对sdb1的扩容， 注意，此种情况不要在生产场景操作，仅作为演示用，生产场景一般是事先规划好不会出现扩容需求，非I/O密集应用可以采用LVM实现规范动态扩容。 以下是扩容实战步骤。 1）记录分区的柱面起始信息： [root@cs6 ~]# fdisk -l /dev/sdb Disk /dev/sdb: 1073 MB, 1073741824 bytes 255 heads, 63 sectors/track, 130 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x1bc7d413 Device Boot Start End Blocks Id System /dev/sdb1 1 26 208813+ 83 Linux /dev/sdb2 27 52 208845 83 Linux 2）卸载分区： [root@cs6 ~]# umount /mnt/data1 [root@cs6 ~]# umount /mnt/data2 [root@cs6 ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_cs6-lv_root 26G 834M 24G 4% / tmpfs 931M 0 931M 0% /dev/shm /dev/sda1 477M 28M 424M 7% /boot 3）重新分区： [root@cs6 ~]# fdisk /dev/sdb WARNING: DOS-compatible mode is deprecated. It's strongly recommended to switch off the mode (command 'c') and change display units to sectors (command 'u'). Command (m for help): d Partition number (1-4): 1 Command (m for help): d Selected partition 2 Command (m for help): n Command action e extended p primary partition (1-4) p Partition number (1-4): 1 First cylinder (1-130, default 1): Using default value 1 Last cylinder, +cylinders or +size{K,M,G} (1-130, default 130): 52 Command (m for help): p Disk /dev/sdb: 1073 MB, 1073741824 bytes 255 heads, 63 sectors/track, 130 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x1bc7d413 Device Boot Start End Blocks Id System /dev/sdb1 1 52 417658+ 83 Linux Command (m for help): w The partition table has been altered! Calling ioctl() to re-read partition table. Syncing disks. [root@cs6 ~]# partprobe /dev/sdb [root@cs6 ~]# mount /dev/sdb1 /mnt/data1 [root@cs6 ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_cs6-lv_root 26G 834M 24G 4% / tmpfs 931M 0 931M 0% /dev/shm /dev/sda1 477M 28M 424M 7% /boot /dev/sdb1 194M 1.8M 182M 1% /mnt/data1 [root@cs6 ~]# ls /mnt/data1 1.html 2.html 3.html 4.html 5.html lost+found [root@cs6 ~]# resize2fs /dev/sdb1 #<==在线调整磁盘大小， resize2fs 1.41.12 (17-May-2010) Filesystem at /dev/sdb1 is mounted on /mnt/data1; on-line resizing required old desc_blocks = 1, new_desc_blocks = 2 Performing an on-line resize of /dev/sdb1 to 417656 (1k) blocks. The filesystem on /dev/sdb1 is now 417656 blocks long. [root@cs6 ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_cs6-lv_root 26G 834M 24G 4% / tmpfs 931M 0 931M 0% /dev/shm /dev/sda1 477M 28M 424M 7% /boot /dev/sdb1 392M 2.3M 369M 1% /mnt/data1 [root@cs6 ~]# ls /mnt/data1 1.html 2.html 3.html 4.html 5.html lost+found 但是数据还是只有sdb1里的了，sdb2的数据丢失了。 此种方法不适合生产场景扩容，比较规范方法是通过LVM逻辑卷管理进行扩容，扩容后也需要resize2fs进行最终实现扩容。