PASSWD(1)						    BSD General Commands Manual 						 PASSWD(1)

NAME

     passwd -- modify a user's password

SYNOPSIS

     passwd [user]
     passwd [-d files | -l] [user]
     passwd [-d nis | -y] [user]
     passwd [-d krb5 | -k] [principal]

DESCRIPTION

     passwd changes the user's password.  First, the user is prompted for their current password.  If the current password is correctly typed, a
     new password is requested.  The new password must be entered twice to avoid typing errors.

     The new password should be at least six characters long and not purely alphabetic.  Its total length must be less than _PASSWORD_LEN (cur-
     rently 128 characters).  Numbers, upper case letters and meta characters are encouraged.

     All options may not be available on all systems.

     -d database
	   This option specifies the password database that should be updated.	The following databases are supported:

	   files  This specifies that the password change should be applied to the local password file.  When changing only the local password,
		  passwd uses pwd_mkdb(8) to update the password databases.

	   nis	  This specifies that the password change should be applied to the NIS password database.  The rpc.yppasswdd(8) daemon should be
		  running on the master NIS server.

	   krb5   This specifies that the user's Kerberos 5 password should be changed.  The host must be configured to use Kerberos.  See
		  krb5.conf(5).

     -l    This is the equivalent of -d files.

     -y    This is the equivalent of -d nis.

     -k    This is the equivalent of -d krb5.

     If a password database is not specified, passwd will change the password database as determined by the Pluggable Authentication Module (PAM)
     library.

     The type of cipher used to encrypt the password depends on the configuration in passwd.conf(5).  It can be different for local and NIS pass-
     words.

FILES

     /etc/master.passwd  The user database
     /etc/passwd	 A Version 7 format password file
     /etc/passwd.XXXXXX  Temporary copy of the password file

SEE ALSO

     chpass(1), login(1), pwhash(1), passwd(5), passwd.conf(5), pam(8), pwd_mkdb(8), vipw(8)

     Robert Morris and Ken Thompson, UNIX password security.

HISTORY

     A passwd command appeared in Version 6 AT&T UNIX.

BSD
								 February 25, 2005							       BSD