Use system performance tools for Linux to display process statistics.
Use Filebeat to deal with many small log files.
Protect Netdata using basic access authentication.
Install netdata on Debian Buster to perform real-time performance monitoring.
Convert outdated system activity information binary datafile to current format, so it could be read by up-to-date application.
You already know how to collect and report system activity information, so it is the best time to learn how to export already collected data.
Use netstat, ss or files inside proc filesystem to count TCP connections.
Collect and report system activity information using sysstat a system performance tools for the Linux operating system.
Install and configure Dashing with Icinga 2 to use the external board for your Icinga2 instance.
Upgrade icinga2 and its web-interface using official/dedicated repository and PostgreSQL database.