#sysadmin

How to run your own Heroku-style PaaS with Dokku: installing it, deploying by git push, and attaching a database to an app.

The gap between something that works and something you can be responsible for is not features. It is backups you have restored, deploys you can undo, logs that survive the crash, and alerts that reach a human.

POODLE killed SSLv3 for good. The nginx configuration that follows from that — protocols, cipher suite, forward secrecy, OCSP stapling and HSTS — and the two lines that matter more than the cipher list everyone copies.

Scaling out with cloud instances or scaling up with bigger machines: what StackOverflow's scale-up architecture says about the trade-off.

Purge, ban and tag-based invalidation in Varnish 3 — why banning a regex does not free memory the way you think, and how surrogate keys turn a hundred invalidations into one.

Forking, detaching from the terminal, PID files and signal handling in PHP — plus an honest look at the one problem the language does not let you solve, and what to do about it.

How to recover a Mac after installing Ubuntu's bootloader into the MBR, on a machine that boots from EFI and GPT.

How to configure pam-pkcs11 so the Spanish DNI-e electronic ID card works as your login credential on Ubuntu 12.04.

Every step to turn an Ubuntu 12.04 box into a Jenkins continuous integration server for PHP projects.

How to serve a remote Git repository over HTTP with push support and digest authentication, and why you might prefer it to SSH.