Listing all users on Linux is best done with the getent passwd command. This isn’t the only way, but it should work an practically any system. Unlike other methods, it uses your systems /etc/nsswitch.conf configuration to show users from all sources. The format is the format used in the file /etc/passwd. $ getent passwd root:x:0:0:root:/root:/bin/bash… Read More »
Linux ACL permissions are based on the draft POSIX 1003.1e. Even though ACLs are in use, the standard never made it out of the draft status. I assume you have a solid grasp on regular file permissions. If not, I suggest reading my guide on the topic before working with ACLs. Use Cases Access control… Read More »
Listing files in a package with dnf is easy. Just follow the example below: # dnf repoquery -l crontabs Last metadata expiration check: 0:12:18 ago on Sat 04 Jan 2020 09:40:27 AM EST. /etc/cron.daily /etc/cron.hourly /etc/cron.monthly /etc/cron.weekly /etc/crontab /etc/sysconfig/run-parts /usr/bin/run-parts /usr/share/licenses/crontabs /usr/share/licenses/crontabs/COPYING /usr/share/man/man4/crontabs.4.gz /usr/share/man/man4/run-parts.4.gz Replace crontabs with the name of the package you wish to… Read More »
UPDATE 2023 April 12: I was going to build RPMs to post here, but found that MATE packages are available in EPEL. Follow the instructions here for setting up the EPEL repositories. I am going to leave the instructions up to assist package maintainers and for anyone interested in the process of building a major… Read More »
I couldn’t find a Tomcat package in the standard repositories or EPEL, so I will walk you through installing Tomcat on CentOS 8. It is a relatively straightforward process. The latest version available at the time of writing (2019 November 23) is 9.0.29, so that is the version I will use in the examples. All… Read More »
The CentOS 8 repositories provide HAProxy version 1.8.15. You may want or need features in newer versions. Fortunately, installing HAProxy 2.0.9 (Latest stable version as of 2019 November, 21) from source is relatively straightforward. The steps to do so are: Install required packages Download the HAProxy source code Compile and install HAProxy Create an unprivileged… Read More »
This guide will walk you through setting up CentOS 8 to use an LDAP directory server for authentication. I am assuming you have a directory server up and running. If you don’t, you can follow these two guides to install and configure OpenLDAP: Install OpenLDAP From Source – CentOS 8 Configure OpenLDAP In this guide,… Read More »
With both DNF and YUM, there are three ways to remove repositories. One of the methods is specific to RHEL. If you are on a system that doesn’t have the dnf command, you can use the yum command instead. Using subscription-manager The subscription-manager program is specific to RHEL and specific to repositories maintained by Red… Read More »
Listing installed packages with dnf is straightforward. Unlike rpm, dnf also shows you the repository packages were installed from. The following example demonstrates listing all packages installed on a system. # dnf list installed Installed Packages acl.x86_64 2.2.53-1.el8 @anaconda audit.x86_64 3.0-0.10.20180831git0047a6c.el8 @anaconda audit-libs.x86_64 3.0-0.10.20180831git0047a6c.el8 @anaconda The left column displays the name of the package along… Read More »
There are a few ways to add a user to a group in Linux. I will cover two methods using the command line. Both methods require the ability to use the root account or the sudo command. Desktop environments often have GUI tools to do this. If you wish to use the GUI, check your… Read More »