Linux file system becomes read-only fix

A simple and temporary way for a Linux system to restart or to become read-only causes the site to fail to access normally:

One

1. Mount:

Used to see which module input is read-only, typically shown as:

/DEV/HDA1 on/type ext3 (rw)

None On/proc type proc (rw)

Usbdevfs ON/PROC/BUS/USB type USBDEVFS (rw)

None on/dev/pts type devpts (rw,gid=5,mode=620)

/dev/hda5 on/home type ext3 (rw)

None On/dev/shm type TMPFS (rw)

/dev/hda2 on/usr/local type ext3 (rw)

/DEV/NB1 on/earthview/raw type ext3 (RO) (changed to read-only)

2, if found RO, re-mount, or Umount later remount

3, UMOUNT/DEV/NB1

If you find a hint "device is busy", find out what process is making him busy

Fuser-m/mnt/data will show the PID using this module

Fuser-mk/mnt/data will kill the PID directly.

Then you can re-mount.

4, there is also a method is direct remount, command for

Mount-o Rw,remount/mnt/data

Two

Specific in-depth approach, different circumstances can be selected by oneself:

Server/var/log/messages Error:

END_REQUEST:I/O error, Dev SDA, Sector 122194293 Buffer I/O error on device sda1, logical block 446493 lost page write du E to I/O error on SDA1

Here's the whole process.

[Email protected] ~]# Fdisk-lu #第一步: Find the partition where the local slice is located.

disk/dev/sda:73.4 GB, 73407868928 bytes

255 heads, Sectors/track, 8924 cylinders, total 143374744 sectors

Units = sectors of 1 * MB = bytes

Device Boot Start End Blocks Id System

/DEV/SDA1 * 4096574 2048256 Linux

/dev/sda2 4096575 75778604 35841015-up Linux

/dev/sda3 75778605 129034079 26627737+-up Linux

/DEV/SDA4 129034080 143364059 7164990 5 Extended

/dev/sda5 129034143 139267484 5116671-up Linux

/dev/sda6 139267548 143364059 2048256, Linux swap

[Email protected] ~]# tune2fs-l/dev/sda3 |grep "Block size" #找到block大小.

Block size:4096

(122194293-75778605) *512/4096 = 528691 Use the formula to calculate the logical block address

b = (int) ((l-s) *512/b)

[Email protected] ~]# Debugfs

Debugfs 1.35 (28-feb-2004)

Debugfs:open/deb/sda3

/deb/sda3:no such file or directory while opening filesystem

Debugfs:open/dev/sda3

Debugfs:icheck 582391

Block Inode Number

582391 277584

Debugfs:ncheck 277584

Inode Pathname

277584/users/inn.net.cn/data/upload/download/innshow004.rar

Debugfs:quit

[[Email protected] ~] #dd if=/dev/zero of=/dev/sda1 bs=4096 count=1 seek=582391 #找到这个快的文件之后, need to do backup, we force it to set to 0 bytes.

[[Email protected] ~]# Sync

2009-10-14

This article is from the "Five Corners" blog, please be sure to keep this source http://hi289.blog.51cto.com/4513812/1764624

Linux file system becomes read-only fix