more timer options

docs/admin-guide/configuration/software/timers.md

@@ -1,5 +1,8 @@
 # Systemd Timers for Regular Tasks
 
+
+## Create New Timer
+
 To have custom executables run regulary on given time/interval, you may use the `base::timers` Hiera key:
 
 ```
@@ -12,6 +15,9 @@ base::timers:
             persistence:  false
         service_options:
             Environment: 'SOME_ENV=some_value'
+        service_unit_options:
+            OnSuccess: 'dnf-automatic'
+            OnFailure: 'send-failure-email'
 ```
 
 This then creates both the required timer and service unit files for systemd.
@@ -26,3 +32,9 @@ Optional is
 - `timer_options` for additional configuration in the `Timer` section of the timer unit. In the example it is `persistence` which signals if the timer should run immediately after boot when the node was switched of on the last scheduled run time (default is `false`).
 - `service_options` for additional configuration in the `Service` section of the service unit.
 
+## Enable/Disable Existing Timer
+```
+base::timers:
+    'certbot':
+        enable: true
+```