Auto-Update Docker Containers — Watchtower with Selective Rules, Notifications, and Graceful Rollouts

Keeping Docker containers updated is the kind of chore you automate once and forget about — until a container silently runs a four-month-old image with five CVEs because you forgot to docker compose pull && up -d. Watchtower solves this. It watches your running containers, checks for new images, and restarts them with the latest tag — all on a cron schedule. But a naive “update everything” setup will break your database container and nuke your uptime. ...

May 11, 2026 · 9 min · 1777 words · GnTech