Linux Change password solution to authentication token manipulation error

Transferred from: http://blog.163.com/junwu_lb/blog/static/1916798920120103647199/

Authentication Token manipulation Error
The cause of this error occurs:

1, the partition has no space to cause.

2,/etc/passwd and/etc/shadow different steps

But this time the above two does not work, through DF to see the root partition and 40% remaining.

1, try to change the password, an error occurred

# passwd
Changing password for user root.
New UNIX Password:
Bad Password:it is the too short
Retype new UNIX Password:
Passwd:authentication Token manipulation Error

2, synchronous/etc/passwd and/etc/shadow error
#pwconv
Pwconv:can ' t lock passwd file

3, see Permissions No exception, there is no process to lock the file
# LL/ETC/PASSWD
-rwxr--r--1 root root 2752 Dec 17:29/etc/passwd
# fuser-u/ETC/PASSWD
# lsof |grep passwd

4, CP lock file Error, insufficient space to indicate

# cp/tmp/.pwd.lock/etc/
Cp:cannot Create regular file '/etc/.pwd.lock ': No space left on device

5, the above error woke me up, check is really inode full, delete useless files
#df-I.
Filesystem inodes iused IFree iuse% mounted on
/dev/sda5 2562240 2562240 0 100%/
/DEV/SDA1 50200 50153 1%/boot
/dev/sda2 51300000 51299988 1%/data/cache1
/DEV/SDB1 51300000 7080311 44219689 14%/data/cache2
/DEV/SDB2 9863168 9863157 1%/data/proclog
None 215907 1 215906 1%/DEV/SHM
/dev/sda3 3842720 305795 3536925 8%/usr
/dev/sda7 3162112 7893 3154219 1%/var
6, again change the password still error, so try to modify/etc/passwd also appeared error

# chmod 777/ETC/PASSWD
chmod:changing permissions of '/etc/passwd ': Operation not permitted
7, the implementation of CHATTR
#chattr-I./etc/passwd
# lsattr-v/ETC/PASSWD
2095582053-------------/etc/passwd

# chattr-i/etc/shadow

8. Synchronizing files
Pwconv

9. Successful Password change
passwd
Changing password for user root.
New UNIX Password:
Bad Password:it is the too short
Retype new UNIX Password:
Passwd:all authentication tokens updated successfully.

Pwconv function Description: Turn on the user's projection password.
Syntax: Pwconv
Additional note: The user and group passwords in the Linux system are stored in files named passwd and group, which are located in the/etc directory. As the system works, anyone can read them, creating a security flaw. The projection password changes the password inside the file into the shadow and Gshadow files in the/etc directory, only allows the System Manager to read, and replaces the original password with the "X" character, which effectively strengthens the security of the system.
Pwconv: Turn on the user's shadow password.
Generally to use Pwconv to synchronize the password, the following, it's workflow:
Pwconv relies on the cipher area ' X ' in passwd to synchronize the two files with/etc/passwd and/etc/shadow, and/etc/passwd to control the items in/etc/shadow:
A: If/etc/shadow does not exist, then Pwconv will use/ETC/PASSWD to establish
B: If/etc/shadow already exists, then:
1. If the entry already exists in passwd and not in the shadow, add the relevant entry in the shadow
2. If the entry already exists in shadow and not in the passwd, delete the relevant entry from the shadow

Linux Change password solution to authentication token manipulation error