Odown product news and updates

Yes. Two domains can share one IP address, and most of the web works this way. The server tells them apart using the TLS SNI field and the HTTP Host header.

Changing nameservers does not cause downtime by itself. It causes downtime when the new nameservers answer differently from the old ones.

An incident commander coordinates the response to a major incident and fixes nothing themselves. Their authority comes from the role, not from seniority.

DNS does not propagate. Old answers expire from caches, and the TTL you set before the change controls the wait. Record changes clear in minutes to hours.

Use 300 seconds before a change, 3600 for records that move occasionally, and 86400 for records that never move. Here is the full ladder with the reasoning.

A domain loading the wrong site is a lookup problem at one of four layers. Trace the delegation, the record, the server, and the cache, in that order.

Certbot renewal has five stages and any one can fail silently. Check the timer, the 30 day window, the challenge, the write, and the reload, in that order.

Renewing a certificate and serving it are different steps. If your site still shows expired, the new file exists but something is still presenting the old one.

A wildcard covers one level of subdomains under one domain. A SAN certificate covers a named list across many domains. Three questions decide which you need.

Yes. Public CAs can issue certificates for IP addresses, and Let's Encrypt has offered them free since January 2026, with a six day lifetime.