Add test for upgrading from previous version of oss to current

tasks/elasticsearch-config.yml

@@ -86,9 +86,29 @@
     content: ''
   when: ansible_os_family == 'RedHat'
 
-- name: Delete Default Sysconfig File
+- name: Check if default systemd file exists
+  stat:
+    path: "{{ sysd_script }}"
+  register: sysd_stat_result
+
+- name: Remove if it is a normal file
+  file:
+    path: "{{ sysd_script }}"
+    state: absent
+  when: not sysd_stat_result.stat.islnk
+
+- name: Create a symbolic link to the default systemd location to the first instance running on this host
   become: yes
-  file: dest="{{ sysd_script }}" state=absent
+  file:
+    state: link
+    src: "{{ instance_sysd_script }}"
+    path: "{{ sysd_script }}"
+  when:
+  - use_system_d
+  - not sysd_stat_result.stat.islnk
+  notify:
+  - reload systemd configuration
+  - restart elasticsearch
 
 - name: Delete Default Configuration File
   become: yes