Containers on Homelab Journal

Building a Safe Auto-Update System for Docker After a 2 AM Outage

Mon, 09 Mar 2026 00:00:00 +0000

The 2 AM Wake-Up Call
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I woke up to find my CI/CD platform had been down for 8 hours. Semaphore, the Ansible automation engine that manages my entire homelab, was stuck in a crash loop:

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/usr/local/bin/server-wrapper: line 295: syntax error: unexpected "&&"
/usr/local/bin/server-wrapper: line 295: syntax error: unexpected "&&"
/usr/local/bin/server-wrapper: line 295: syntax error: unexpected "&&"

The same error, repeating every few seconds. The container would start, hit the broken entrypoint script, crash, and restart. Endlessly.

Lesson Learned: Why I Replaced Watchtower with WUD Across My Homelab

Wed, 04 Feb 2026 00:00:00 +0000

The Problem
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Watchtower had been my go-to for automatic Docker container updates across 8+ services. It worked… mostly. But I kept running into issues:

Opt-out model is dangerous - Watchtower watches ALL containers by default. I had to remember to add com.centurylinklabs.watchtower.enable=false to containers I didn’t want updated. Forgetting meant surprise updates.
No visibility - Updates happened silently at 4 AM. I only knew something updated when it broke. No dashboard, no easy way to see pending updates.

Containers on Homelab Journal

Building a Safe Auto-Update System for Docker After a 2 AM Outage

The 2 AM Wake-Up Call #

Lesson Learned: Why I Replaced Watchtower with WUD Across My Homelab

The Problem #

The 2 AM Wake-Up Call
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The Problem
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