Here place for user templates for alerts, groups and notifications. Default templates stored in includes/templates/ <- DO NOT TOUCH files here Use this dir for overrides. # change current dirrectory to your observium dir cd /opt/observium # copy (or create) new template from defaults, for example HTML email notifications: cp includes/templates/notification/email_html.tpl templates/notification/ # edit copied file: nano templates/notification/email_html.tpl FORMATS Notifications uses Mustache/CTemplate syntax. Examples and demo see here: https://mustache.github.io/ But note, not all features of mustache supported. Supported: * standart php comments * {{! %^ }} - intext comments * {{var}} - escaped var * {{{var}}} - unescaped var * {{var.subvar}} - dot notation vars * {{.}} - implicit iterator * {{#var}} some text {{/var}} - if/list condition * {{^var}} some text {{/var}} - inverted (negative) if condition Groups and alert templates uses xml syntax. Examples see in includes/templates/ dir.