Question: How to enable logging in firewalld for CentOS/RHEL 8? 1. Edit the /etc/firewalld/firewalld.conf and change the “LogDenied” line to the following: # vi /etc/firewalld/firewalld.conf LogDenied=all 2. Edit the /etc/sysconfig/firewalld and add or change the “FIREWALLD_ARGS” line to the following: # vi /etc/sysconfig/firewalld FIREWALLD_ARGS=–debug=10 3. Restart the firewalld service: # systemctl restart firewalld.service 4. Check […]
“Failed to Synchronize Cache For Repo ‘repo_name’, Ignoring This Repo” – CentOS/RHEL 8 error
The Problem While installing package or listing using dnf or yum commands getting below errors: # dnf repolist .. Failed to synchronize cache for repo ‘xxx’, ignoring this repo. Failed to synchronize cache for repo ‘yyy’, ignoring this repo. While checking the dnf logs: # tail -f /var/log/dnf.log 2019-08-12T10:58:13Z INFO — logging initialized — 2019-08-12T10:58:13Z […]
How to delete unused kernels and keep only the running kernel in CentOS/RHEL
Question: How to keep only running kernel in a CentOS/RHEL Linux system? Keeping less than 2 kernels in a Linux system is strongly not recommended. There are several reasons for this recommendation: If an installation of a new kernel is interrupted or aborted in any before it completes successfully, rebooting the system with that kernel […]
How to Delete unnecessary Entry in /etc/shadow
Question: How to remove all the unnecessary user entries in /etc/shadow file. 1. Create a backup copy of /etc/shadow file. # cp -p /etc/shadow /etc/shadow.backup 2. Ensure the user is not existing anymore in /etc/password file. # cat /etc/passwd | grep [userid] 3. Edit the /etc/shadow file, look for the line and remove the unnecessary […]
How to see what has changed in Kernel Versions (changelog) in CentOS/RHEL
Please check the following solution to see the changes, bug fixes and security improvements in kernel versions. Download the kernel version through ULN or yum.oracle.com and execute the “# rpm -qp –changelog [kernel rpm package]” command in order to see changes in the kernel versions. # rpm -qp –changelog [kernel rpm package] For example: # […]
User Account “systemd-bus-proxy”
This post provides information about the user account systemd-bus-proxy. The user account systemd-bus-proxy was used in the past by systemd-bus-proxyd service. systemd-bus-proxy:x:999:997:systemd Bus Proxy:/:/sbin/nologin Starting systemd-219-32, bus-proxyd was removed. Therefore, it is no longer in use in later systemd versions. * Mon Feb 20 2017 Lukas Nykryn – 219-32 … – remove bus-proxyd (#1317518) NOTE: […]
How to Manage Virtual Machines from the CentOS/RHEL 8 Web Console-Cockpit
The high-level steps are outlined below: Installing the Cockpit Virtual Machines Module Creating a Virtual Machine in Cockpit Starting the Installation Add other servers in Cockpit to montior The Web Console is installed by default on Oracle Linux 8 installations unless you do a minimal installation. The Web Console is not started by default, so […]
How to Install Cockpit’s Web Console in CentOS/RHEL 8
1. Install the cockpit package On CentOS/RHEL 8 8 systems with non-minimal installations, the cockpit package is included by default. Otherwise, it would need to manually install Cockpit. In either case, running the following command ensures that the package is installed and is up to date. # sudo dnf install cockpit 2. Enable and start […]
How to Install Mokutil package on CentOS/RHEL 7 and 8
The mokutil package is used to update the MOK list with a certificate or hash. Mokutil package is not available for CentOS/RHEL 6. It is available for CentOS/RHEL 7 and 8. If you are using CentOS/RHEL 8, make sure you have the CentOS/RHEL 8 (x86_64) BaseOS Latest repository enabled and then run command below to […]
Kubernetes Command Line Reference (Cheatsheet)
Creating Objects Create resource: $ kubectl apply -f ./<file_name>.yaml Create from multiple files: $ kubectl apply -f ./<file_name_1>.yaml -f ./<file_name_2>.yaml Create all files in directory: $ kubectl apply -f ./<directory_name> Create from url: $ kubectl apply -f https://<url> Create pod: $ kubectl run <pod_name> –image <image_name> Create pod, then expose it as service: $ kubectl […]