Blog
Blog
Writing from the realuptime team on monitoring, incident response, and what we're building. New posts every few days.
What a TCP port check proves, and what it does notA TCP port monitor answers one question: does this host accept a connection on this port, from here, right now? That is the right question for databases, mail, SSH and brokers, and the wrong one for a web app. Where each check type fits, and what each one cannot see.Your cron job stopped and nobody noticed. Heartbeat monitoring, explained.Uptime checks cannot see a backup script or a queue worker, because there is nothing to probe. Heartbeat monitoring turns the check around: the job reports in, and silence is the alarm. How it works, how to size the grace period, and the mistakes that make it useless.How often should an uptime monitor check your site? Less than the interval decidesOne minute, five minutes, thirty seconds: the check interval only sets a ceiling on how fast you find out. Confirmation, timeouts, and region quorum decide the real number. The math, with worked examples.ChatGPT is down. The status page checkmarks are green. Both are true.Is ChatGPT down right now? Measured from four regions: the OpenAI API is fine, the ChatGPT product is not, and the component board stayed green through a major incident.What it takes to track 900+ services honestlyA week ago the outage catalog covered 195 services. It now covers more than 900. The story is not the count, it is the rejection list behind it: what we would not add, and why.RealUptime is publicWe launched on Product Hunt today, and our listings on AlternativeTo and SaaSHub are live. Here is what we built, why, and a launch discount.Uptime monitor false positives: the page you should not have gottenFalse positive alerts train teams to ignore real ones. How we decide a failure is real before waking anyone up, and what we refuse to page on.When the monitor is the problemAn uptime monitor that fails quietly is worse than no monitor at all. We keep a public register of the ways ours can fail and what happens for each.One internet, four speedsWe ping the same 190 services from Virginia, California, Frankfurt, and Tokyo every few minutes. The answers disagree more than you'd think.Status pages that can't lieMost status pages are marketing documents that occasionally mention incidents. We built ours so that the tempting lies are structurally unavailable.