Opscode on Opscode - Linux & Infrastructure Engineering

A complete account of how Linux names network interfaces, why those names change without warning, and how to write configuration that survives it.

Root cause analysis of repeated link up/down transitions at 10 and 100 Mbps during boot on Intel i226 controllers, from an embedded ARM platform to COTS cards on a desktop.

Measuring device-under-test (DUT) latency with i350 hardware timestamping and network namespaces: repeater hub vs 10/100 switch vs gigabit switch.

NFSv3 with AUTH_SYS trusts whatever UID and GID the client claims.

I work with industrial Linux systems that have strict real-time requirements.

Building a GPS-disciplined PTP grandmaster from a NanoPi R5S-LTS and a NEO-M8N GPS module.

Building a GPS-disciplined PTP grandmaster from a Raspberry Pi CM4 and SR1723U10 GPS module.

Setting up sss_ssh_authorizedkeys in a lab environment uncovered two security issues in a common SSSD configuration: disabled AD accounts could authenticate via SSH key, and revoked keys stayed valid for up to 90 minutes after removal from AD.

What actually breaks when you assign two Linux NICs to the same subnet, when it's genuinely necessary, and exactly what you must configure if you have no choice.

How a CMMC Level 2 requirement for automatic session termination exposed a subtle OpenSSH behavior change, and why I ended up using autolog instead of native sshd_config directives.

I inherited a set of Ubuntu servers with inconsistent Dynamic DNS updates and ended up submitting a fix to the systemd man page.

The infrastructure behind opscode.io - Hugo, S3, CloudFront, Route 53, and a GitHub Actions pipeline that deploys on every git push.