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Friday, October 11, 2019

Managing User Accounts In Linux Essay

Linux’s most notable advantage over other operating systems such as Windows and Mac is security and in order for a user to modify critical components of the system, such as user accounts, is to have access rights of a ROOT. The root is at the top level of Linux’s user hierarchy and has all the privileges to access all resources. To login as root, a user must use the command su username. After pressing the ENTER key, the system will prompt the user to type in the corresponding password. After entering the correct password, the user will inherit full access privileges including the right to modify other user’s account information. Attempting to enter the correct password will deny the user from inheriting the root’s privileges. # su – [screenshot] Let us now attempt to create a new user called ‘bozo’. But first, let us check if that username is not yet taken. # id bozo [screenshot] Since username bozo is still available we can now create his user account. # useradd bozo -d /home/bozo -u 600 We have just created a username called bozo and makes his default folder under /home/bozo and gave him the UID of 600. by the way, UID’s are unique identifiers of users. Users can be a representation of both human users and services running in the Linux system. UID’s are used by Linux in relation to his password and privilege information stored in the /etc/passwd, /etc/shadow and /etc/group. One of the very first thing Linux does when creating a new user is to copy the files from the skeleton folder, which contains whatever files the admin wants to give to new users, into the newly created user’s folder. Now, let us try to take a look at those files by displaying a detailed listing of files including hidden ones. # ls –la /home/skel/ So far so good. Now let us try creating another user and call her bozoette. # useradd bozo -d /home/bozo -u 600 We had an error. As stated earlier, UID’s are unique. Since we attempted to create a user and assigned the same UID with bozo, the system denied our request. But what if we do want give bozoete the UID #600? One of the many ways to do it is to first change bozo’s UID, say 601 and then create bozoette’s user account using the newly-vacant UID of 600. Change bozo’s UID from 600 to 601. # id bozo # usermod -u 601 bozo # id bozo Then create bozoette’s new account with UID 600. # useradd bozoette -d /home/bozoette -u 600 Now we have two new users bozo(uid:601) and bozoette(uid:600) with user directories /home/bozo and /home/bozoette, respectively. Note that user accounts remain inactive until a password is assigned to them. Let us now activate the two new user accounts by assigning passwords to them. # passwd bozo # passwd bozoette Users bozo and bozoette are now active and users can now login to the system using the correct username and password combinations for the accounts. REFERENCES Linux Headquarters. Adduser: Adding A New User. Advanced Horizons. Linux Users. Mario P. Free November 28, 2007. Tutorial @HowTo. fm. Command Line User Management. Notaras, George. 6 November 2005. G-Loaded! User management from the command line

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