/usr/lib/systemd/system does not exist on Ubuntu 18.04.

tasks/main.yml

@@ -257,10 +257,21 @@
   when: tomcat_use_systemd_unit
   tags: ['tomcat', 'tomcat_instances', 'tomcat_init']
 
+- name: Check if /usr/lib/systemd/system exists
+  ansible.builtin.stat:
+    path: /usr/lib/systemd/system
+  register: systemd_system_path
+  tags: ['tomcat', 'tomcat_instances', 'tomcat_init']
+
+- name: Define the installation path of the systemd unit
+  ansible.builtin.set_fact:
+    systemd_unit_dest_dir: '{% if systemd_system_path.stat.exists %}/usr/lib/systemd/system{% else %}/etc/systemd/system{% endif %}'
+  tags: ['tomcat', 'tomcat_instances', 'tomcat_init']
+
 - name: Install the instances systemd unit
   ansible.builtin.template:
     src: tomcat-service.j2
-    dest: "/usr/lib/systemd/system/tomcat-instance-{{ item.http_port }}.service"
+    dest: "{{ systemd_unit_dest_dir }}/tomcat-instance-{{ item.http_port }}.service"
     mode: "0644"
     owner: root
     group: root

templates/catalina.properties.j2

@@ -124,7 +124,7 @@ org.apache.catalina.startup.ContextConfig.jarsToSkip=
 
 # Additional JARs (over and above the default JARs listed above) to skip when
 # scanning for TLDs. The list must be a comma separated list of JAR file names.
-org.apache.catalina.startup.TldConfig.jarsToSkip=tomcat7-websocket.jar
+org.apache.catalina.startup.TldConfig.jarsToSkip=tomcat-websocket.jar
 
 #
 # String cache configuration.