文件系统宕机，重启后报错，无法启动
处理流程：
1.编辑/etc/fstab将文件系统挂载去掉
# vim /etc/fstab
#/dev/xvdb /data ext3 defaults 1 2
#/dev/xvdc /data1 ext3 defaults 0 0
2.重启进入系统，对两个分区进行fsck修复检测(建议使用screen，避免中途被打断)
# screen -S xvdc
# fsck -y /dev/xvdc
fsck from util-linux-ng 2.17.2
e2fsck 1.41.12 (17-May-2010)
/dev/xvdc: recovering journal
/dev/xvdc has gone 510 days without being checked, check forced.
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
/dev/xvdc: ***** FILE SYSTEM WAS MODIFIED *****
/dev/xvdc: 425/32768000 files (68.5% non-contiguous), 4265913/131072000 blocks
# fsck -y /dev/xvdb
fsck from util-linux-ng 2.17.2
e2fsck 1.41.12 (17-May-2010)
/dev/xvdb contains a file system with errors, check forced.
Pass 1: Checking inodes, blocks, and sizes
Free blocks count wrong for group #2637 (10474, counted=14592).
Fix? yes
Free blocks count wrong for group #2638 (9318, counted=10345).
Fix? yes
Free blocks count wrong for group #2639 (11172, counted=12429).
Fix? yes
Free blocks count wrong for group #2640 (8375, counted=8887).
Fix? yes
Free blocks count wrong (22177812, counted=22268375).
Fix? yes
Inode bitmap differences: -19694041 -19709957 -19718159
Fix? yes
Free inodes count wrong for group #2404 (7638, counted=7639).
Fix? yes
Free inodes count wrong for group #2406 (8104, counted=8105).
Fix? yes
Free inodes count wrong for group #2407 (8088, counted=8089).
Fix? yes
Free inodes count wrong (32383813, counted=32383816).
Fix? yes
/dev/xvdb: ***** FILE SYSTEM WAS MODIFIED *****
/dev/xvdb: 384184/32768000 files (63.4% non-contiguous), 108803625/131072000 blocks
3.检测完磁盘以后打开挂载，并重新挂载，重启系统
# cat /etc/fstab
#
# /etc/fstab
# Created by anaconda on Thu Aug 14 21:16:42 2014
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
UUID=94e4e384-0ace-437f-bc96-057dd64f42ee / ext4 defaults,barrier=0 1 1
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
/dev/xvdb /data ext3 defaults 1 2
/dev/xvdc /data1 ext3 defaults 0 0
# ll /data
total 0
# ll /data1
total 0
# mount /dev/xvdb /data
# mount /dev/xvdc /data1
重启系统
# reboot