Practical articles on AI, DevOps, Cloud, Linux, and infrastructure engineering.
A field-tested workflow for diagnosing why a systemd unit refuses to start, from status output to exit codes to the usual root causes.
When a Linux box misbehaves, the same dozen problems come up again and again. This is the map: what each symptom means and the fast path to the fix.
A likelihood-ordered checklist for tracing "Permission denied" on Linux through mode bits, ownership, ACLs, SELinux, and mount options.
The kernel killed your process to save the box, and the log looks like noise until you know exactly which fields to read.
A field-tested workflow for finding which process burns your CPU and whether the time is user, system, or iowait.
Load average counts more than CPU demand, so a high number needs a diagnostic path before you reach for a fix.
A practical method for reading free, top, and ps correctly so you attribute Linux memory to a real cause instead of guessing.
Track down what owns a busy port, decide whether to kill it or rebind, and stop TIME_WAIT from blocking your restart.
A field guide to reclaiming Linux disk space when df reports full but du can't find where the bytes actually went.
When a process hits its file descriptor ceiling everything breaks at once; here is how to find the real limit and raise it correctly.
A pod that logged fine for weeks starts throwing EMFILE at 3am. Here's how to tell a real file-descriptor leak from a limit that's just set too low.
A node flips to NotReady and pods start disappearing. Here's the order we check things in, the usual culprits, and how to recover without making it worse.
