Logging | John Nessime

Nginx Rate Limiting and Bot Mitigation Without Blocking Real Users

Post category:Networking Technical Guides Web Security

A limit_req block that parses cleanly can still be doing absolutely nothing, or throttling every visitor behind one CDN edge. This guide covers Nginx rate limiting and bot mitigation as they actually behave in production: getting the key right behind a proxy, what burst and nodelay do to your traffic shape, sizing zones correctly, rolling out in dry run mode, and layering bot handling from robots.txt through user agent maps to firewall escalation.

Docker Logs Ate My Disk: A Working Guide to Log Drivers and Rotation

Post category:DevOps Docker System Administration Troubleshooting

Docker's default logging driver writes container output to a JSON file with no size limit and no rotation. This is a practical guide to Docker log rotation: what the defaults actually do, why your daemon.json change did nothing, why deleting the log file did not free any disk, and how to choose between json-file, local, journald and shipping logs off the box.

journald vs rsyslog: Where Your Linux Logs Actually Live

Post category:DevOps Linux System Administration

On a stock Linux server, journald and rsyslog are both running and both storing the same events, with retention policies that don't know about each other. Here's where each log line actually lives, the three failure modes that bite in production, and how to decide which copy you keep.

Docker Compose in Production: What Works and What Quietly Burns You

Post category:DevOps Docker Technical Guides

Running Docker Compose in production is a reasonable choice for a single host, but the defaults were chosen for a laptop. A walk through the failure families that actually bite: the deploy gap, unrotated logs filling the disk, anonymous volumes, published ports that bypass your firewall, secrets in environment variables, and health checks that report without acting.

Build a Secure AI Medical Assistant on AWS: The Boundaries That Actually Leak

Post category:Case Studies Cloud Computing DevOps Technical Guides

A practical architecture for a secure AI medical assistant on AWS, organised by the boundary the data crosses: the input box, your own invocation logs, cross-Region inference routing, the retrieval index, and clinical accuracy. Includes real commands, the failure modes that stay invisible until an audit, and the trade-offs worth knowing before you build.

Zero Errors, Zero Records: Monitoring Salesforce Integrations with CloudWatch and Grafana

Post category:Cloud Computing DevOps Technical Guides

The error count was zero every day for three weeks. So was the invocation count. A stopped integration and a healthy one produce identical graphs, and every CloudWatch default is tuned to stay quiet when data stops arriving. Four signals worth emitting, and the alarm config that actually fires.

One Label Too Many: Centralized Logging With Loki Without Wrecking It

Post category:DevOps System Administration Technical Guides

Loki was fast until someone added one more label. Now queries time out during incidents and the index no longer fits in memory. Here's the model you have to internalise, what replaced Promtail, and how to keep labels, retention and storage costs under control.

Green Check, Broken Build: How to Build a Fail Fast Pipeline That Explains Why

Post category:DevOps Technical Guides Troubleshooting

A green pipeline that ships a broken build is worse than a red one. Here is how to order stages so failures surface in seconds, stop shell pipes from swallowing exit codes, and write failure output that tells the next engineer exactly what to fix.

Metrics, Logs and Traces: What Each One Answers

Post category:DevOps System Administration Web Performance

Metrics tell you that something is wrong. Traces tell you where. Logs tell you why. Use them in that order and each step narrows the search — start with logs and you are grepping a firehose. Here is what each one is actually for, and the field that connects all three.

HIPAA Compliance on AWS: The Gaps That Pass Every Security Check

Post category:Case Studies Cloud Computing Technical Guides Web Security

A working engineer's guide to HIPAA compliance on AWS, organised by the gap between the control you configured and the obligation you actually carry. Covers BAA account scope, the eligible services list as a contract boundary, KMS key policy versus the encryption checkbox, what "six years" really applies to, backup and restore scope, and the subprocessor chain nobody inventories.