SysAdmin

A quick one-liner to flush every message out of the Exim mail queue. Useful when a misconfigured relay or a flood of bounce messages has clogged up your server.

Learn how to manually decompress an RPM package into a working directory using rpm2cpio and cpio, without installing the package.

A quick reference for enabling verbose output when sending mail from the command line, so you can see the full SMTP transaction and diagnose delivery issues.

Learn how to configure MySQL’s log_output variable to write slow query and general logs to files instead of tables, and why that matters for performance and log management.

A quick reference for running a forced, verbose ext filesystem check with automatic repairs and timestamped logging.

A quick three-command recipe for grabbing a full thread backtrace from a running httpd process with gdb, useful when Apache appears hung or unresponsive.