Flashcards in Administrative Tasks Deck (65):
Format of /etc/passwd entry
username:password:UID:Primary GUID:comment:homedir:default shell
User IDs under _____ are reserved for system users
What can you change the shell section of an /etc/passwd entry to that will cause the user to not be able to login?
Normal user accounts have IDs from ___ to ____
500 to 1000
What should permissions be on /etc/passwd
What should permissions be on /etc/shadow
Verifies the integrity of the users and authentication information by checking /etc/passwd and /etc/shadow
usually used to set user's full name
Used to set the user's home directory
Set the user's expiration date in the form YYYY-MM-DD
Set your own encrypted password
Do not create the home directory
Create the home directory /home/username if it does not exist
Defines all the other groups that the member belongs to. Separate each group by a comma .
Sets the default group that is the users group when the user first logs in
useradd -f INACTIVE
defines the number of days after a password expires that an account is permanently disabled. Value of 0 disables immediately after the password expires and -1 disables the entire inactive feature.
useradd -k skel_dir
Use skel_dir as the skeleton directory instead of /etc/skel
Location for default settings for the useradd command
Used to change and manage users' expiry dates
set the date that the user's password will expire
Set the number of days of inactivity after a password expired before locking the account
Set minimum number of days between password changes
Set maximum number of days which a password is valid
Used to delete a group (cannot do this if any user has the group as their primary group)
Specify a new group id
When used with -g it allows two groups to share the same group id
Specify a new group name
Force the deletion of the user even if they are logged in.
Will also delete home directory and mail
Will remove the home directory and mail.
Note: does not remove all other files owned by the user outside of their home directory
Set the user's home directory
Set the date on which the account will expire
Number of days after a password expires until account is permanently disabled
default login group
List of extra groups a user is part of
Change the login name of the user
Lock the account
File containing list of groups and all the members associated with the group
Specify a group id
Chooses a group id less than 500 used for system groups
Forces group creation even if there is already a group by that name
Specify number of days a password must remain valid
Minimum number of days between password changes
Make account inactive after password has been expired for some number of days
Display current shell process
Display exit value of the last command
Display the PID of the last job run in background
Display the name of the shell or script
Location that crontabs are stored for users
List pending AT jobs
File in which you list users that you want to deny use of at
File in which you list users that you want to specifically allow use of at
File in which you list users that you want to deny use of cron
File in which you list users that you want to allow use of cron
Will remove the at task with the specified jobnum
Program that causes commands specified to be executed once at a specified later time.
End things with ctrl + d
at now + 1 minute
Will perform the specified commands 1 minute from now
minute hour day month day-of-week command
What do locale settings determine?
Language, country, currency symbols, etc.
Language environment variable
Are timezone settings part of locale settings?
Location of the time zone file
How to set the correct timezone?
ln –s some timezone file from /usr/share/zoneinfo to /etc/timezone or copy the
correct zone file from /usr/share/zoneinfo and replace /etc/timezone
GUI tool to help make time zone changes
Utility used to convert between character sets