diff --git a/backlog/tasks/task-6 - Fix-rinbox.online-rmail.online-tunnel-routing-502-404.md b/backlog/tasks/task-6 - Fix-rinbox.online-rmail.online-tunnel-routing-502-404.md
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+---
+id: TASK-6
+title: Fix rinbox.online/rmail.online tunnel routing (502/404)
+status: Done
+assignee: []
+created_date: '2026-02-25 09:03'
+labels:
+  - infrastructure
+  - bugfix
+dependencies: []
+priority: high
+---
+
+## Description
+
+<!-- SECTION:DESCRIPTION:BEGIN -->
+rinbox.online returned 502 and rmail.online returned 404 due to Next.js HOSTNAME binding and missing Traefik rules. Fixed by: (1) adding export HOSTNAME=0.0.0.0 in entrypoint.sh to override Docker's container ID injection, (2) adding rmail.online and www.rmail.online to Traefik router Host rules in docker-compose.yml, (3) fixing Netcup remote to fetch from rinbox-online repo instead of old rmail-online.
+<!-- SECTION:DESCRIPTION:END -->
+
+## Final Summary
+
+<!-- SECTION:FINAL_SUMMARY:BEGIN -->
+Fixed two routing issues: rinbox.online 502 (Next.js binding to wrong network interface — solved with HOSTNAME=0.0.0.0 in entrypoint.sh) and rmail.online 404 (missing Traefik Host rule). All 25 r* domains now returning HTTP 200.
+<!-- SECTION:FINAL_SUMMARY:END -->