THE NOTEBOOK / 12 ENTRIES
Articles
Working explanations for the next time a small system asks a difficult question.
A small server needs a baseline
Record enough context to distinguish a system problem from an application symptom.
Reading TCP under load
Use congestion, flow control and application demand as separate explanations.
BBR, buffers and the delay budget
Why a larger buffer and a faster congestion controller are different decisions.
QUIC is more than UDP
Understand the layers before interpreting an HTTP/3 or tunnel trace.
Certificates are a lifecycle
Issuance is only the first part of a dependable TLS deployment.
DNS: from label to destination
Separate authoritative data, recursive caches and application-level routing.
Caddy as a small static origin
Keep the document root, TLS automation and deployment process easy to inspect.
SSH access with an exit plan
Temporary access should be scoped, attributable and easy to remove.
Firewall changes you can explain
Small, owned rule changes are easier to audit and recover.
Monitoring small VPS machines
A handful of well-defined measurements can be more useful than a busy dashboard.
A network debugging ladder
Locate the failing layer before changing a setting.
IPv4 and IPv6 without assumptions
Treat dual-stack service as two paths that each need validation.