Linux中让用户的密码必须有一定的长度，并且符合复杂度?
出于安全的考虑，我们在建立用户或是对用户进行管理的时候，对于密码的设置往往有一定的严格要求，过于简单的密码会对系统产生">安全隐患，所以我们可以通过一些规则来实现强制要求输入复杂的密码。
操作如下：
修改PASS_MIN_LEN的长度即可
[root@localhost software]# vi /etc/login.defs
# # Please note that the parameters in this configuration file control the # behavior of the tools from the shadow-utils component. None of these # tools uses the PAM mechanism, and the utilities that use PAM (such as the # passwd command) should therefore be
configured elsewhere. Refer to # /etc/pam.d/system-auth for more information. # # *REQUIRED* #
Directory where mailboxes reside, _or_ name of file, relative to the # home directory. If you _do_
define both, MAIL_DIR takes precedence. # QMAIL_DIR is for Qmail # #QMAIL_DIR Maildir MAIL_DIR /var/spool/mail #MAIL_FILE .mail # Password aging controls: # # PASS_MAX_DAYS Maximum number of days a password may be used. # PASS_MIN_DAYS Minimum number of days allowed between password changes. # PASS_MIN_LEN Minimum acceptable password length. # PASS_WARN_AGE Number of days warning given before a password expires. # PASS_MAX_DAYS 99999 PASS_MIN_DAYS 0 PASS_MIN_LEN 5 PASS_WARN_AGE 7 # # Min/max values for automatic uid selection in useradd # UID_MIN 500 UID_MAX 60000 # # Min/max values for automatic gid selection in groupadd # GID_MIN 500 GID_MAX 60000 # # If
defined, this command is run when remo
ving a user. "/etc/login.defs" 66L, 1816C # # Please note that the parameters in this configuration file control the # behavior of the tools from the shadow-utils component. None of these # tools uses the PAM mechanism, and the utilities that use PAM (such as the # passwd command) should therefore be configured elsewhere. Refer to # /etc/pam.d/system-auth for more information. # # *REQUIRED* # Directory where mailboxes reside, _or_ name of file, relative to the # home directory. If you _do_ define both, MAIL_DIR takes precedence. # QMAIL_DIR is for Qmail # #QMAIL_DIR Maildir MAIL_DIR /var/spool/mail #MAIL_FILE .mail # Password aging controls: # # PASS_MAX_DAYS Maximum number of days a password may be used. # PASS_MIN_DAYS Minimum number of days allowed between password changes. # PASS_MIN_LEN Minimum acceptable password length. # PASS_WARN_AGE Number of days warning given before a password expires. # PASS_MAX_DAYS 99999 PASS_MIN_DAYS 0 PASS_MIN_LEN 5 PASS_WARN_AGE 7 # # Min/max values for automatic uid selection in useradd # UID_MIN 500 UID_MAX 60000 # # Min/max values for automatic gid selection in groupadd # GID_MIN 500 GID_MAX 60000 # # If defined, this command is run when removing a user. # It should remove any at/cron/print jobs etc. owned by # the user to be removed (passed as the first argument). # #USERDEL_CMD /usr/sbin/userdel_local # # If useradd should create home directories for users by default # On RH systems, we do. This option is overridden with the -m flag on # useradd command line. # CREATE_HOME yes # The permission mask is
initialized to this value. If not specified, # the permission mask will be initialized to 022. UMASK 077 # This enables userdel to remove user groups if no members exist. # USERGROUPS_ENAB yes # Use SH
A512 to encrypt password. ENCRYPT_METHOD SHA512