The usermod command works somewhat like useradd command, with similar parameters. The usermod utility changes an existing account, unlike the useradd that adds a new account. The basic syntax of the command is: usermod [-c comment] [-d home_dir [-m]] [-e expire_date] [-f inactive_time] [-g initial_group] [-G group [,…]] [-l login_name] [-p passwd] [-s shell] ↵ [-u uid [-o]] [-L|-U] username...
Rclone is an open source tool that can sync Linux systems with the most important cloud storage services: Google Drive, Amazon Drive, S3, Dropbox, Backblaze B2, One Drive, Box, Hubic, Cloudfiles, Google Cloud Storage, Yandex and more others. Its appearance was determined by the need of synchronizing a local directory with the space in the cloud owned by users, a space that most often has mounting...
When you manage a system with many user accounts, groups, and, by default, passwords, it is necessary that individual information for a particular account can be viewed quickly. It may be tedious to try to locate information about a particular user in a file with hundreds or thousands of records. In most cases, the grep command is used to search for specific records in a file: $ grep mvps...
WPScan is a free, non-commercial tool useful for scanning the vulnerabilities of WordPress-based websites. It was designed to test the security of these websites. In addition to security testing, WPScan is also useful in finding the theme or plugins used by a particular WordPress website – I am sure that not only once you were curious to find out which template or extension uses a particular...
The chage (change age) command allows you to modify user accounts for their expiration. Linux allows you to configure your accounts so they expire automatically if either of the following conditions is met: 1. the password was not changed within the specified time period; 2. if the system date exceeds a predetermined date. These settings are controlled by the chage utility, which has the...
The gpasswd command is the equivalent of the passwd command for groups. This command provides the ability to modify some group features and assign administrators to users who can perform administrative functions relative to their group. The syntax of the command is the following one: gpasswd [-a user] [-d user] [-R] [-r] [-A user [, …]] [-M user[,…]] group Adding a user The -a user...
Groupadd command – adding groups to Linux The groupadd command provides the ability to add a new group to Linux. It is similar to useradd, but has fewer options. The basic syntax of the groupadd command is: groupadd [-g GID [-o]] [-r] [-f] [-K] group_name The parameters used by this command have the following meanings: GID specification We can specify a specific GroupIDentifier (GID) using...
I’m not used to forget things, especially important ones, such as passwords. But unfortunately, such things can happen to anyone – even to me. And I’ve been to it recently: I’ve changed the password for a CentOS 7 system just before I went on vacation with a new password, designed by another algorithm than the one I have been using for years and years, but after a short...
We often have to find a solution to a Linux problem quickly – if we do not have access to the internet, or we need to solve the problem in a very short time. Let’s suppose you’ve just decided to opt out of your shared hosting and you’ve got your first VPS, connected to SSH, and you started configuring it. Below are the ways you can access all the documentation that your...
Linux file systems support some additional attributes for files, attributes that can be assigned or changed using the chattr command. With chattr we can do the following: • do not change the attribute that points to a file: if we set attribute A, Linux will not update the date when we accessed a specific file. This can reduce disk access time, which in particular can save laptop battery life (or...