Domnr BlogDomain portfolio management, DNS change tracking, SSL monitoring, and uptime monitoring — in one place.https://domnr.app/Uptime monitoring: HTTP vs TCP checks, and how often to run themhttps://domnr.app/blog/uptime-monitoring-http-vs-tcp/https://domnr.app/blog/uptime-monitoring-http-vs-tcp/Not all uptime checks are equal. Here's the difference between HTTP and TCP monitoring, how to pick check intervals, and what actually counts as "down."Sat, 13 Jun 2026 00:00:00 GMTYour SSL certificate is about to expire: a calm checklisthttps://domnr.app/blog/ssl-certificate-about-to-expire/https://domnr.app/blog/ssl-certificate-about-to-expire/An expired TLS certificate throws a full-page security warning and can take a site down outright. Here's what to check, and how to stop it from happening by surprise.Tue, 02 Jun 2026 00:00:00 GMTDNS propagation explained: why your change isn't live yethttps://domnr.app/blog/dns-propagation-explained/https://domnr.app/blog/dns-propagation-explained/You updated a DNS record an hour ago and it's still serving the old value. Here's what "propagation" actually is, why TTL controls it, and how to check.Tue, 19 May 2026 00:00:00 GMTDNS change monitoring: catch the change before it breaks somethinghttps://domnr.app/blog/why-dns-change-monitoring-matters/https://domnr.app/blog/why-dns-change-monitoring-matters/A single edited DNS record can take a site offline or silently reroute your email. Here's why DNS changes are so easy to miss, and how monitoring catches them early.Tue, 05 May 2026 00:00:00 GMTWHOIS and RDAP: what your domain record actually tells youhttps://domnr.app/blog/what-whois-rdap-tells-you/https://domnr.app/blog/what-whois-rdap-tells-you/WHOIS is more than a registrar name. Here's how to read a domain record — expiry, status codes, nameservers — and why RDAP is quietly replacing it.Tue, 21 Apr 2026 00:00:00 GMTHow to never miss a domain renewal againhttps://domnr.app/blog/never-miss-a-domain-renewal/https://domnr.app/blog/never-miss-a-domain-renewal/A lapsed domain can take a site offline, break email, and even put your name on the open market. Here's a simple system for tracking renewals across every registrar.Tue, 07 Apr 2026 00:00:00 GMTIntroducing the Domnr bloghttps://domnr.app/blog/introducing-the-domnr-blog/https://domnr.app/blog/introducing-the-domnr-blog/Why we built a fast, crawlable public surface with Astro — and what you can expect to read here.Tue, 24 Mar 2026 00:00:00 GMT