passwd [options] [LOGIN]

-a, --all : This option can be used only with -S and shows the status for all users.
-d, --delete : Delete a users password (make it empty).
-e, --expire : Immedi­ately expire an account's password.
-i, --inactive INACTIVE : This option is used to disable an account after the password has been expired for a number of days. After an account has had an expired password for INACTIVE days, the user may no longer sign on to the account.
-k, --keep­-to­kens : Indicate password change should be performed only for expired authen­tic­ation tokens (passw­ords).
-l, --lock : Lock the password of the named account. This does not disable the account. The user may still be able to login using another authen­tic­ation token (e.g. a SSH key).
-n, --mindays MIN_DAYS : Set the minimum number of days between password changes to MIN_DAYS. A value of zero indicates that the user may change their password at any time.
-S, --status : Display account status inform­ation. (logi­n,l­ock­ed/­no/­usable passwo­rd,date of last password change,min age, max age, warning period, inactivity period)
-u, --unlock : Unlock the password of the named account.
-w, --warndays WARN_D­AYS : Number of days warning prior to a required password change.
-x, --maxdays MAX_DAYS : Set the maximum number of days a password remains valid. After MAX_DAYS, the password will need to be changed.

gpasswd [option] GROUP

-a, --add USER : Add the user to the named group.
-d, --delete USER : Remove the user from the named group.
-r, --remo­ve-­pas­sword : Remove the password from the named group.
-R, --rest­rict : Restrict the access to the named group.
-A, --admi­nis­trators USER,... : Set the list of admini­str­ative users.
-M, --members USER,... : Set the list of group members.
 

useradd [options] LOGIN

-b, --base-dir BASE_DIR : Default system base directory if -d is not specified.
-d, --home HOME_DIR : Use HOME_DIR as the value for the user's login directory.
-e, --expi­redate EXPIRE­_DATE : Date on which the user account will be disabled. (YYYY­-MM­-DD)
-f, --inactive INACTIVE : Number of days after a password expires until the account is disabled. (0 disables account on expira­tion. -1 disables the feature.)
-g, --gid GROUP : The group name or number of the users initial login group. The group name must exist.
-G, --groups GROUP1­[,...] : List of supple­mentary groups for the user. Subject to same restri­ctions as -g.
-k, --skel SKEL_DIR : The skeleton directory to be copied in the users home directory, upon creation. Only valid if -m option specified
-K, --key KEY=VA­LUE : Overrides /etc/l­ogi­n.defs defaults. Multiple -K options can be specif­ied.
-l, --no-l­og-­init : Do not add the user to the lastlog and faillog databases.
-m, --crea­te-­home : Create the user's home directory if it doesn't exist.
-M : Don't create home directory.
-N, --no-u­ser­-gr­oup : Do not create a group with the same name as the user.
-o, --non-­uni­que : Allow the creation of a user account with a duplicate UID. Only valid along with -u option
-p, --password PASSWORD : The encrypted password. NOT Recomm­end­ed!
-r, --system : Create system account
-s, --shell SHELL : The name of the user's login shell.
-u, --uid UID : The numerical value of the users ID. Must be unique unless -o option used
-U, --user­-gr­oup : Create group with the same name as the user
-Z, --seli­nux­-user SEUSER : The SELinux user for the users login.

groupmod [options] GROUP

-g, --gid GID : The group ID will be changed to GID.
-n, --new-name NEW_GR­OUP : Group name will be changed from GROUP to NEW_GROUP.
-o, --non-­uni­que : When used with -g, allows setting the group GID to a non-unique value.
-p, --password PASSWORD : The encrypted password. NOT Recomm­end­ed!
 

usermod [options] LOGIN

-a, --append : Add user to supple­mentary group(s). Use only with the -G option.
-d, --home HOME_DIR : The user's new login directory.
-e, --expi­redate EXPIRE­_DATE : Date on which the user account will be disabled (YYYY­-MM­-DD)
-g, --gid GROUP : The group name/n­umber of the user's new initial login group.
-G, --groups GROUP1­[,G­ROU­P2...] : A list of supple­mentary groups which the user is also a member
-l, --login NEW_LO­GIN : The name of the user will be changed from LOGIN to NEW_LOGIN.
-L, --lock : Lock a users password. (Can't use option with -p or -U)
-m, --move­-home : Move the content of the users home directory to the new location.
-o, --non-­uni­que : when used with the -u option, this option allows to change the user ID to a non-unique value.
-p, --password PASSWORD : Set password explicitly via shell. Not recomm­end­ed!
-s, --shell SHELL : The name of the users new login shell.
-u, --uid UID : The new numerical value of the users ID. Must be unique unless the -o option is used.
-U, --unlock : Unlock a users password. (Can't use this option with -p or -L.)
-Z, --seli­nux­-user SEUSER : The SELinux user for the users login.

groupadd [options] GROUP

-f, --force : This option causes the command to simply exit with success status if the specified group already exists.
-g, --gid GID : The numerical value of the groups ID. This value must be unique, unless the -o option is used.
-K, --key KEY=VA­LUE : Overrides /etc/l­ogi­n.defs defaults (GID_MIN, GID_MAX and others). Multiple -K options can be specif­ied.
-o, --non-­uni­que : This option permits to add a group with a non-unique GID.
-p, --password PASSWORD : The default is to disable the password. (NOT RECOMM­END­ED: the password will be visible by users listing the proces­ses.)
-r, --system : Create a system group.
 

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Comments

DaveChild DaveChild, 07:27 20 Dec 11

Wow, this is great! Nice job!

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