How to fix “Failed to synchronize cache for repo appstream” Recently I had explored upgrading CentOS 7 to CentOS 8 and during the process, I encountered the error: Failed to...
How to upgrade CentOS 7 to CentOS 8 Linux This tutorial will guide you step-by-step to upgrade CentOS 7 to Centos 8. Step 1: Boot up any CentOS 7...
Error Access denied need PROCESS privilege [MySQL] I was trying to back up the database using the MySQL dump command, however, the command failed with an error...
“firewall-cmd: command not found” on CentOS 8 [Solved] Recently I started a CentOS 8 VM on my OpenStack setup. When trying to configure firewall rules using firewall-cmd, encountered...
How to Install Certbot on CentOS Stream 8 [Let’s Encrypt] In 2017, we wrote an article on migrating to Let’s Encrypt from StarSSL and also you’ll see a number of...
Upgrade CentOS 8 to CentOS Stream As you all know, CentOS 8 has reached its EOL on 31st Dec 2021, it’s time to upgrade your CentOS...
How to Install xclip on CentOS 8 I recently started using CentOS 8 on my server and I couldn’t see the package xclip installed on CentOS 8...
Failed to download metadata for repo ‘AppStream’ [CentOS] I had installed a minimalist CentOS 8 on one of my servers. Installation went successful, however, when I tried to...
How to check sudoers syntax I have written many articles on sudoers in the past such as best practices and solved many errors related to...
Find number of Lines of Code from GitHub Repository How many lines of code did you write? Well, that was the question asked by one of the interviewers in...
Unable to establish connection using ssh2_connect() in PHP I have used the ssh2_connect() function to establish a connection to a remote SSH server. But it works on one...
error: src refspec main does not match any [GIT] Created a private repository on GitHub and when tried to push the files from my server using the below commands,...
How to stop Apache mod_rewrite log message [Apache] I had written a few rewrite rules to disable HTTP TRACE and TRACK as part of VAPT. When looking at...
How to setup WSO2 with Let’s Encrypt certificate Setting up an SSL certificate for WSO2 API Manager is not straightforward, as it requires creating Keystore and adding an...
How to Enable HSTS (HTTP Strict Transport Security) Policy in Nginx & Apache According to Netcraft’s study, 95% of HTTPS servers are vulnerable to Man-in-the-Middle attacks. Therefore, it is very important to implement...
Error accessing backend service – WSO2 forgot password I had configured WSO2 successfully and NGINX reverse proxy is set up as well. However, clicking forgot password link from...
[CentOS 7 Apache]: Permission denied: file permissions deny server access Whenever I configure Apache on CentOS 7, most of the time I get “(13) Permission denied: file permissions deny server...
Rubygems-update requires Ruby version >= 2.3.0 [Fix] I was trying to update rubygems and ended up with an error “Error installing rubygems-update: rubygems-update requires Ruby version >=...
Using multiple patterns at once with Sed command Here’s a question from one of our regular readers Mr. Manish. His question is, how to use multiple patterns at...
Setup WSO2 with NGINX Reverse Proxy for custom URLs By default, WSO2 interfaces such as Publisher, Developer portal, and Carbon are accessed via port :9443/publisher, :9443/devportal and :9443/carbon respectively....