useradd의 환경을 지배하는 3개의 파일(디렉토리)실무1편- /etc/default/useradd파일 실무활용 개론

[root@RockyLinux01 ~]# cat /etc/default/useradd

# useradd defaults file

GROUP=100

HOME=/home

INACTIVE=-1

EXPIRE=

SHELL=/bin/bash

SKEL=/etc/skel

CREATE_MAIL_SPOOL=yes

[root@RockyLinux01 ~]#

[root@RockyLinux01 ~]# ls -al /etc/skel

합계 32

drwxr-xr-x.   4 root root   111  6월 14 15:24 .

drwxr-xr-x. 182 root root 12288  6월 21 16:18 ..

-rw-r--r--    1 root root    18  1월 24 07:42 .bash_logout

-rw-r--r--    1 root root   141  1월 24 07:42 .bash_profile

-rw-r--r--    1 root root   492  1월 24 07:42 .bashrc

drwxr-xr-x    4 root root    39  4월 28 15:57 .mozilla

-rw-r--r--.   1 root root   658  5월 15  2022 .zshrc

drwxr-xr-x    2 root root    24  6월 14 15:24 public_html

[root@RockyLinux01 ~]#

[root@RockyLinux01 ~]# cat /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.

#

#

# Delay in seconds before being allowed another attempt after a login failure

# Note: When PAM is used, some modules may enforce a minimum delay (e.g.

#       pam_unix(8) enforces a 2s delay)

#

#FAIL_DELAY             3

# Currently FAILLOG_ENAB is not supported

#

# Enable display of unknown usernames when login(1) failures are recorded.

#

#LOG_UNKFAIL_ENAB       no

# Currently LOG_OK_LOGINS is not supported

# Currently LASTLOG_ENAB is not supported

#

# Limit the highest user ID number for which the lastlog entries should

# be updated.

#

# No LASTLOG_UID_MAX means that there is no user ID limit for writing

# lastlog entries.

#

#LASTLOG_UID_MAX

# Currently MAIL_CHECK_ENAB is not supported

# Currently OBSCURE_CHECKS_ENAB is not supported

# Currently PORTTIME_CHECKS_ENAB is not supported

# Currently QUOTAS_ENAB is not supported

# Currently SYSLOG_SU_ENAB is not supported

#

# Enable "syslog" logging of newgrp(1) and sg(1) activity.

#

#SYSLOG_SG_ENAB         yes

# Currently CONSOLE is not supported

# Currently SULOG_FILE is not supported

# Currently MOTD_FILE is not supported

# Currently ISSUE_FILE is not supported

# Currently TTYTYPE_FILE is not supported

# Currently FTMP_FILE is not supported

# Currently NOLOGINS_FILE is not supported

# Currently SU_NAME is not supported

# *REQUIRED*

#   Directory where mailboxes reside, _or_ name of file, relative to the

#   home directory.  If you _do_ define both, MAIL_DIR takes precedence.

#

MAIL_DIR        /var/spool/mail

#MAIL_FILE      .mail

#

# If defined, file which inhibits all the usual chatter during the login

# sequence.  If a full pathname, then hushed mode will be enabled if the

# user's name or shell are found in the file.  If not a full pathname, then

# hushed mode will be enabled if the file exists in the user's home directory.

#

#HUSHLOGIN_FILE .hushlogin

#HUSHLOGIN_FILE /etc/hushlogins

# Currently ENV_TZ is not supported

# Currently ENV_HZ is not supported

#

# The default PATH settings, for superuser and normal users.

#

# (they are minimal, add the rest in the shell startup files)

#ENV_SUPATH     PATH=/sbin:/bin:/usr/sbin:/usr/bin

#ENV_PATH       PATH=/bin:/usr/bin

#

# Terminal permissions

#

#       TTYGROUP        Login tty will be assigned this group ownership.

#       TTYPERM         Login tty will be set to this permission.

#

# If you have a write(1) program which is "setgid" to a special group

# which owns the terminals, define TTYGROUP as the number of such group

# and TTYPERM as 0620.  Otherwise leave TTYGROUP commented out and

# set TTYPERM to either 622 or 600.

#

#TTYGROUP       tty

#TTYPERM                0600

# Currently ERASECHAR, KILLCHAR and ULIMIT are not supported

# Default initial "umask" value used by login(1) on non-PAM enabled systems.

# Default "umask" value for pam_umask(8) on PAM enabled systems.

# UMASK is also used by useradd(8) and newusers(8) to set the mode for new

# home directories if HOME_MODE is not set.

# 022 is the default value, but 027, or even 077, could be considered

# for increased privacy. There is no One True Answer here: each sysadmin

# must make up their mind.

UMASK           022

# HOME_MODE is used by useradd(8) and newusers(8) to set the mode for new

# home directories.

# If HOME_MODE is not set, the value of UMASK is used to create the mode.

HOME_MODE       0700

# 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_WARN_AGE   7

# Currently PASS_MIN_LEN is not supported

# Currently SU_WHEEL_ONLY is not supported

# Currently CRACKLIB_DICTPATH is not supported

#

# Min/max values for automatic uid selection in useradd(8)

#

UID_MIN                  1000

UID_MAX                 60000

# System accounts

SYS_UID_MIN               201

SYS_UID_MAX               999

# Extra per user uids

SUB_UID_MIN                100000

SUB_UID_MAX             600100000

SUB_UID_COUNT               65536

#

# Min/max values for automatic gid selection in groupadd(8)

#

GID_MIN                  1000

GID_MAX                 60000

# System accounts

SYS_GID_MIN               201

SYS_GID_MAX               999

# Extra per user group ids

SUB_GID_MIN                100000

SUB_GID_MAX             600100000

SUB_GID_COUNT               65536

#

# Max number of login(1) retries if password is bad

#

#LOGIN_RETRIES          3

#

# Max time in seconds for login(1)

#

#LOGIN_TIMEOUT          60

# Currently PASS_CHANGE_TRIES is not supported

# Currently PASS_ALWAYS_WARN is not supported

# Currently PASS_MAX_LEN is not supported

# Currently CHFN_AUTH is not supported

#

# Which fields may be changed by regular users using chfn(1) - use

# any combination of letters "frwh" (full name, room number, work

# phone, home phone).  If not defined, no changes are allowed.

# For backward compatibility, "yes" = "rwh" and "no" = "frwh".

#

#CHFN_RESTRICT          rwh

# Currently LOGIN_STRING is not supported

# Currently MD5_CRYPT_ENAB is not supported

#

# If set to MD5, MD5-based algorithm will be used for encrypting password

# If set to SHA256, SHA256-based algorithm will be used for encrypting password

# If set to SHA512, SHA512-based algorithm will be used for encrypting password

# If set to BLOWFISH, BLOWFISH-based algorithm will be used for encrypting password

# If set to DES, DES-based algorithm will be used for encrypting password (default)

#

ENCRYPT_METHOD SHA512

#

# Only works if ENCRYPT_METHOD is set to SHA256 or SHA512.

#

# Define the number of SHA rounds.

# With a lot of rounds, it is more difficult to brute-force the password.

# However, more CPU resources will be needed to authenticate users if

# this value is increased.

#

# If not specified, the libc will choose the default number of rounds (5000).

# The values must be within the 1000-999999999 range.

#

#SHA_CRYPT_MAX_ROUNDS 5000

# Currently SHA_CRYPT_MIN_ROUNDS is not supported

# Currently BCRYPT_MIN_ROUNDS and BCRYPT_MAX_ROUNDS are not supported

# Currently CONSOLE_GROUPS is not supported

#

# Should login be allowed if we can't cd to the home directory?

# Default is yes.

#

#DEFAULT_HOME   yes

# Currently ENVIRON_FILE is not supported

#

# 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

#

# Enables userdel(8) to remove user groups if no members exist.

#

USERGROUPS_ENAB yes

#

# If set to a non-zero number, the shadow utilities will make sure that

# groups never have more than this number of users on one line.

# This permits to support split groups (groups split into multiple lines,

# with the same group ID, to avoid limitation of the line length in the

# group file).

#

# 0 is the default value and disables this feature.

#

#MAX_MEMBERS_PER_GROUP  0

#

# If useradd(8) should create home directories for users by default (non

# system users only).

# This option is overridden with the -M or -m flags on the useradd(8)

# command-line.

#

CREATE_HOME     yes

#

# Force use shadow, even if shadow passwd & shadow group files are

# missing.

#

#FORCE_SHADOW    yes

#

# Select the HMAC cryptography algorithm.

# Used in pam_timestamp module to calculate the keyed-hash message

# authentication code.

#

# Note: It is recommended to check hmac(3) to see the possible algorithms

# that are available in your system.

#

HMAC_CRYPTO_ALGO SHA512

[root@RockyLinux01 ~]#