Only pass journal dirs that are present to Journalbeat

Change-Id: I3e65a0a06c452632847a55effd2ce4d0c3cb4ac0

elk_metrics_6x/installJournalbeat.yml

@@ -32,6 +32,11 @@
   tasks:
     - include_tasks: common_task_install_go1.10.1.yml
 
+    - name: Check for journal directory
+      stat:
+        path: /var/log/journal
+      register: journal_dir
+
     - name: Ensure libsystemd-dev is installed
       apt:
         name: "{{ item }}"

elk_metrics_6x/templates/journalbeat.yml.j2

@@ -68,8 +68,9 @@ journalbeat:
   # If you want to open Journal from directory just pass an array consisting of one element
   # representing the path. See: https://www.freedesktop.org/software/systemd/man/sd_journal_open.html
   # By default this setting is empty thus journalbeat will attempt to find all journal files automatically
+{% if journal_dir.stat.exists and journal_dir.stat.isdir %}
   journal_paths: ["/var/log/journal"]
-
+{% endif %}
   #default_type: journal
 
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