Alert design, on-call, SLAs and SLOs, uptime maths, incidents and runbooks.
Measure the load, check it against both the watt and VA ratings, read runtime off the maker's chart, and know when pure sine matters. A worked example included.
Continue reading How to size a UPS for a home lab: VA, watts and runtime ›
Network Monitoring, Uptime & Alerting
A green ping check only proves a kernel answered. What ICMP, TCP, HTTP and synthetic checks each catch, and a layered plan for one web service.
Continue reading Ping is not monitoring: ICMP, TCP and synthetic checks compared ›
Network UPS Tools from the USB cable to a tested shutdown: drivers, upsd, upsmon, what upsc tells you, and which box should go down last.
Continue reading UPS monitoring with NUT: clean shutdowns for a home rack ›
A good runbook is the calm colleague who is awake when you are not. A six-part template, writing tips, and a full example for a core uplink.
Continue reading Runbooks an on-call engineer can use at 3 a.m. ›
99.9 percent of a 30-day month is 43.2 minutes. The window, the maintenance clause and the place you measure from decide the rest.
Continue reading What 99.9 percent really allows: uptime maths and how SLAs are measured ›
A page should mean someone has to act now. Symptom alerts, severity tiers, hysteresis, dependencies and three bad alerts rewritten.
Continue reading Alert fatigue: writing alerts people still read six months later ›
