Upgrade icinga2 and its web-interface using official/dedicated repository and PostgreSQL database.
openssl utility to quickly determine if your web-server still supports deprecated
Define basic authentication on HAProxy load balancer limit access to specific backends.
Pretty print package dependencies from package file itself.
Define allowed HTTP methods on HAProxy load balancer using simple Access Control Lists.
Use encrypted passwords to automatically setup users using configuration management tools like Puppet or Ansible.
Create custom data field to define multiple domain names and service apply rule to verify those SSL certificates.
Check locallly stored SSL certificate using basic utilities like
curl. This knowlege is especially useful when you want to prepare SSL certificate for load balancer.