TOPIC / CATEGORY
Notes in Web & Networking
8 articles
Inspect a TLS Certificate with OpenSSL
Check the certificate a server actually presents, including names, issuer, validity, and chain details.
Troubleshooting Google Public CA and acme.sh
A focused troubleshooting companion for Google Public CA EAB registration, DNS-01 validation, installation, and renewal with acme.sh.
Nginx Location Matching in the Order That Matters
Understand exact, prefix, and regular-expression locations before adding another Nginx block.
A Small HTTP Header Check with curl
Inspect the headers a real GET request receives, follow redirects deliberately, and keep response bodies out of the terminal.
Measure an HTTP Request with curl Without Guessing
Use curl write-out values to separate DNS, connection, TLS, first-byte, and total request time.
Test Nginx Configuration Before Reloading
Use Nginx's configuration test, inspect included files, and reload without replacing healthy workers with a broken configuration.
Google Trust Services Certificates with acme.sh: A 2026 Guide
Issue and renew a Google Trust Services certificate with acme.sh, Google Public CA EAB credentials, and a scoped Cloudflare DNS token.
Check DNS With dig Before Changing It
A compact dig workflow for separating authoritative DNS, recursive caches, and local resolver behavior.