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I tried to install an OpenVPN access server in Centos 6 on a linode VPS.

The installation error occours when adding the user "openvpn". However, the installation is okay for my ubuntu 11.10 distro in another VPS.

The error message is

"useradd: canot open /etc/passwd"

The detail of My "/etc/passwd" file:

"-rw-r--r-- 1 root root 1194 Oct  9 00:33 /etc/passwd"

So how can I add the user "openvpn" to setup the VPN service?


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up vote 0 down vote accepted

I have found out the solution.

The attributes of "/etc/passwd" and "/etc/shadow" are both set hiden in Centos of linode.

Change the attributes of two file by the following two commands:

chattr -ai /etc/passwd
chattr -ai /etc/shadow

Then I can add user by typing:

useradd -s /sbin/nologin openvpn
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