Why the Linux system cannot add user accounts for analysis

Production environment configuration:

Operating system: CentOS 6.6

1. The problem arises:

"SERADD:CANNOTOPEN/ETC/PASSWD" appears when you add an account using the Useradd command

[[Email protected] ~] #useradd-D/home/wwwroot/ftupuser-g ftp-s/sbin/nologin Ftpuser

useradd:cannotopen/etc/passwd

2. reasons for the resulting:

a) After adding the "I" hidden property, the file cannot be changed.

[[Email protected] ~] #chattr +i/etc/passwd

[[Email protected] ~] #chattr +i/etc/shadow

[[Email protected] ~] #chattr +i/etc/group

[[Email protected] ~] #chattr +i/etc/gshadow

b) The last time you use SSH to telnet to the "change" to half is a power outage, restart, or some programs also need to access the properties of a particular file.

3. problem Solving:

[email protected] ~] #chattr-I/etc/passwd

[[Email protected] ~] #chattr-I/etc/shadow

[[Email protected] ~] #chattr-I/etc/group

[[Email protected] ~] #chattr-I/etc/gshadow

through the above approach, there is no problem solved. the "lsattr" command to further review the related properties, found that there is a "chattr +a" permission attribute is not removed, so the right to operate.

[[Email protected] ~] #lsattr/etc/passwd

-----a-------e-/etc/passwd

[[Email protected] ~] #lsattr/etc/passwd

-----a-------e-/etc/passwd

[[Email protected] ~] #lsattr/etc/shadow

-----a-------E-/etc/shadow

[[Email protected] ~] #lsattr/etc/group

-----a-------E-/etc/group

[[Email protected] ~] #lsattr/etc/gshadow

-----a-------E-/etc/gshadow

[[Email protected] ~] #chattr-a/etc/passwd

[[Email protected] ~] #chattr-a/etc/shadow

[[Email protected] ~] #chattr-a/etc/group

[[Email protected] ~] #chattr-a/etc/gshadow

[[Email protected] ~] #lsattr/etc/passwd

-------------E-/ETC/PASSWD

[[Email protected] ~] #lsattr/etc/shadow

-------------E-/etc/shadow

[[Email protected] ~] #lsattr/etc/group

-------------E-/etc/group

[[Email protected] ~] #lsattr/etc/gshadow

-------------E-/etc/gshadow

[[Email protected] ~] #useradd-P/home/wwwroot/ftpuser-g ftp-s/sbin/nologin Ftpuser

[[Email protected] ~] #useradd-P/home/wwwroot/ftpuser-g ftp-s/sbin/nologin Ftpuser

Useradd:user ' Ftpuser ' already exists

solve the problem by doing the above.

This article is from the "linux~dba~mba~edu" blog, make sure to keep this source http://sky9896.blog.51cto.com/2330653/1698416

Why the Linux system cannot add user accounts for analysis