Troubleshooting

How to set up Nagios for server infrastructure monitoring, covering host and service checks, alert notifications, and SLA uptime tracking.…

Debugging Bugzilla email notification failures caused by a 504 gateway timeout when routing outbound mail through Gmail SMTP, with a working…

How to install Ruby 2.0.0-p247 using rbenv and ruby-build on CentOS 6.5, including patching for OpenSSL compatibility issues that break the …

Diagnosing SFTP and port connectivity failures using PortQry on Windows and nmap, nc, and ss on Linux to identify blocked or misconfigured p…

Linux performance monitoring for sysadmins: using top, htop, vmstat, iostat, and sar to track CPU, memory, disk I/O, and system load in real…

A curated list of free open-source alternatives to popular paid Windows software, covering tools like Podman, k3s, and Prometheus for everyd…

How a production ingestion server failure caused by a full disk was diagnosed, and how a pre-flight check script was built to prevent it fro…

How to flash a custom Android ROM on the LG Optimus 2X to fix chronic battery drain and performance issues caused by the stock firmware.…

Useful Linux command-line tricks for sysadmins: splitting PDFs with pdftk, converting file formats, and automating repetitive file operation…

Preparing for the RHCE exam: focusing on command-line tools, hands-on lab practice, and the practical skills Red Hat tests in the performanc…