SELinux (Security-Enhanced Linux) is a security layer on RHEL-family systems that enforces strict rules about what each process can access. It’s valuable, but it sometimes blocks legitimate software and causes “permission denied” errors that aren’t obvious. This guide shows how to check SELinux status and disable it – temporarily or permanently – on CentOS, RHEL, […]
Articles Tagged: server management
How to change crontab editor
When you run crontab -e for the first time, Linux often opens the cron file in vi (or vim), which can be confusing if you don’t know it. The editor crontab uses is controlled by the EDITOR and VISUAL environment variables, so switching it to nano — or any editor you prefer — takes one […]
How to Recursively Change the File’s Permissions in Linux
Changing permissions on a single file is easy with chmod. Doing it across a whole directory tree – hundreds of files and folders – is where people get it wrong. The blanket command chmod -R 755 works, but it makes every file executable, which is incorrect for normal web files. This guide covers the recursive […]
How to install Docker Compose on CentOS 8
⚠ Two updates since the original article: (1) CentOS 8 reached end-of-life on 31 December 2021 – use AlmaLinux 9, Rocky Linux 9, or CentOS Stream. (2) Docker Compose v1 (the docker-compose command) is deprecated. Compose v2 is now a Docker plugin, run as docker compose (with a space). The steps below use the current […]
How to upgrade PHP version on CentOS 7
⚠ CentOS 7 reached end-of-life on 30 June 2024. It no longer receives security updates. If you’re still on CentOS 7, plan a migration to AlmaLinux 9 or Rocky Linux 9 – both are free, RHEL-compatible successors. The modern steps are included below. PHP updates matter for both security and performance – each major version […]
Server management (technical support)
Unihost.com – provides technical support for servers running Linux/Windows operating systems.