193 lines
3.2 KiB
HTML
193 lines
3.2 KiB
HTML
<HTML
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><HEAD
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>Disabling User Accounts</TITLE
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NAME="GENERATOR"
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TITLE="Linux Administration Made Easy"
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TITLE="Changing User Passwords"
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HREF="changing-user-passwords.html"><LINK
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TITLE="Removing User Accounts"
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>Chapter 6. General System Administration Issues</TD
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><DIV
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><H1
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CLASS="SECT1"
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><A
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NAME="DISABLING-USER-ACCOUNTS"
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>6.4. Disabling User Accounts</A
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></H1
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><P
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>To disable a user account, edit, as root, the
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``<TT
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CLASS="LITERAL"
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><TT
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CLASS="FILENAME"
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>/etc/shadow</TT
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></TT
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>'' file (assuming
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you're using shadow passwords; if not, edit the
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``<TT
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CLASS="LITERAL"
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><TT
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CLASS="FILENAME"
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>/etc/passwd</TT
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></TT
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>'' file instead),
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and replace the password (which is stored in its encrypted form) with a
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``*'' asterisk character. All Unix passwords, regardless of length (up
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to a maximum of 8 characters), are stored in the password file as
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encrypted strings of 13 characters. Therefore, by replacing the password
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with a single ``*'' character, it is impossible for the user to sign
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in.</P
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><DIV
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CLASS="NOTE"
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><BLOCKQUOTE
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CLASS="NOTE"
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><P
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><B
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>Note: </B
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>Note: This method will require you to assign a new password to
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the user if you re-enable the account, since the encrypted password field
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will have been replaced. One solution to this which seems to be popular
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among system administrators is to simply prefix the ``*'' asterisk
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character in front of the encrypted password to disable the account, and
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simply removing the asterisk to enable it.</P
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></BLOCKQUOTE
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></DIV
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><P
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>For more information on the
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``<TT
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CLASS="LITERAL"
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><TT
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CLASS="FILENAME"
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>/etc/passwd</TT
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></TT
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>'' and
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``<TT
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CLASS="LITERAL"
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><TT
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CLASS="FILENAME"
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>/etc/shadow</TT
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></TT
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>'' files, see <A
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HREF="shadow-file-formats.html"
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>Section 6.6</A
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> below.</P
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>Prev</A
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>Changing User Passwords</TD
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>Removing User Accounts</TD
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> |