Ansible-manage docker-log-cleanup script and cron (PESO-142) (#128)

docker-log-cleanup.sh lived in the repo but nothing deployed it — the
script and monthly cron on nuremberg-a were set up by hand and got wiped
when the host was reinstalled. Fold both into the docker role so every
docker_hosts member gets the script in /usr/local/bin and a monthly cron,
and it survives a rebuild.

ansible/README.md

@@ -56,7 +56,7 @@ Run a single stage: `ansible-playbook deploy.yml --tags docker`
 |------|-------------|
 | `common` | Base packages, SSH hardening, fish shell, exporters, Alloy |
 | `dotfiles` | Shell config from `dotfiles/` |
-| `docker` | Docker engine install and setup |
+| `docker` | Docker engine install and setup + monthly log-cleanup cron |
 | `docker_services` | Deploy compose files from `services/` |
 | `caddy` | Caddy reverse proxy (helsinki-a) |
 | `status_page` | status.pez.sh generator script + cron |

ansible/roles/docker/tasks/main.yml

@@ -96,3 +96,23 @@
     state: directory
     mode: '0755'
   loop: "{{ docker_services | default([]) }}"
+
+# ── Log maintenance ───────────────────────────────────────────────────────────
+# Truncate oversized container *-json.log files (PESO-142). Mostly a no-op now
+# that logs ship via the Loki driver, but kept as a safety net and managed in
+# IaC so it survives a host rebuild.
+
+- name: Deploy docker-log-cleanup script
+  ansible.builtin.copy:
+    src: "{{ playbook_dir }}/scripts/docker-log-cleanup.sh"
+    dest: /usr/local/bin/docker-log-cleanup.sh
+    mode: '0755'
+
+- name: Schedule monthly docker log cleanup
+  ansible.builtin.cron:
+    name: "Docker log cleanup"
+    minute: "0"
+    hour: "3"
+    day: "1"
+    job: "/usr/local/bin/docker-log-cleanup.sh"
+    user: root

ansible/scripts/docker-log-cleanup.sh

@@ -1,7 +1,12 @@
 #!/bin/bash
-# Truncate large Docker container log files
+# Truncate large Docker container log files.
-# Deployed on: nuremberg-a
+#
-# Cron: 0 3 1 * * /usr/local/bin/docker-log-cleanup.sh
+# Managed by Ansible (docker role) — deployed to /usr/local/bin/ on all
+# docker_hosts and run monthly via cron. Do not edit on the host.
+#
+# Safety net for containers using the json-file log driver; most containers
+# ship logs via the Loki driver and never write *-json.log, so on a healthy
+# host this is usually a no-op.
 
 LOG_DIR=/var/lib/docker/containers
 MAX_SIZE_MB=100