added loki persistent storage

Author: wtripp180901

ansible/roles/kube_prometheus_stack/defaults/main/helm.yml

@@ -198,6 +198,17 @@ kube_prometheus_stack_loki_release_values:
   test_pod:
     image: "bats/bats:{{ kube_prometheus_stack_loki_test_pod_tag }}"
   loki:
+    config:
+      compactor:
+        retention_enabled: true
+      limits_config:
+        retention_period: 72h
+    persistence:
+      enabled: true
+      selector:
+        matchLabels:
+          app.kubernetes.io/name: loki-dir
+      size: "{{ kube_prometheus_stack_loki_persistence_size }}"
     nodeSelector:
       clusterrole: server
     image:

ansible/roles/kube_prometheus_stack/defaults/main/main.yml

@@ -24,6 +24,9 @@ kube_prometheus_stack_loki_chart_version: 2.10.2
 kube_prometheus_stack_loki_image_tag: 2.9.3 # also promtail tag
 kube_prometheus_stack_loki_test_pod_tag: 1.8.2
 
+kube_prometheus_stack_loki_data_dir: "{{ appliances_state_dir }}/loki"
+kube_prometheus_stack_loki_persistence_size: "10Gi"
+
 control_ip: "{{ hostvars[groups['control'].0].ansible_host }}"
 
 grafana_auth_anonymous: false

ansible/roles/kube_prometheus_stack/tasks/main.yml

@@ -82,6 +82,46 @@
           path: "{{ prometheus_db_dir }}"
           type: DirectoryOrCreate
 
+# Loki image seems to be hardcoded to use this uid/gid even when changed in
+# podSecurityContext
+- name: Create Loki group
+  ansible.builtin.group:
+    name: loki
+    gid: 10001
+
+- name: Create Loki user
+  ansible.builtin.user:
+    name: loki
+    uid: 10001
+    group: loki
+
+- name: Create Loki data directory
+  ansible.builtin.file:
+    state: directory
+    path: "{{ kube_prometheus_stack_loki_data_dir }}"
+    owner: 10001
+    group: 10001
+    mode: '775'
+
+- name: Create Loki hostPath volume in /var/lib/state
+  kubernetes.core.k8s:
+    namespace: "{{ kube_prometheus_stack_release_namespace }}"
+    definition:
+      apiVersion: v1
+      kind: PersistentVolume
+      metadata:
+        name: loki-dir
+        labels:
+          app.kubernetes.io/name: loki-dir
+      spec:
+        capacity:
+          storage: "{{ kube_prometheus_stack_loki_persistence_size }}" # not enforced but may be internally by loki?
+        accessModes:
+        - ReadWriteOnce
+        hostPath:
+          path: "{{ kube_prometheus_stack_loki_data_dir }}"
+          type: Directory
+
 - name: Setting up k3s services for OnDemand Exporter
   when: groups['openondemand'] | count > 0
   block: