HERMODR

About

Hermodr is a simple system alert thingie. It runs a number of checks, called scouts, that send a notification if a non-acceptable condition is detected.

It is intended to run periodically, and will only generate output if a problem has been found (unless VERBOSE and/or MOREVERBOSE is set).

Its main alerting channel is ntfy.sh. Set ntfy_enable="YES" to enable it, and remember to change ntfy_topic to your own topic. It can also alert to stdio by setting stdio_enable="YES".

All files in the scouts/ directory need to have the executable bit set.

Currently, it only checks for:

• High load avg
• Letsencrypt certificates about to expire
• Low disk space
• Non-running processes (specific ones)
• High CPU usage
• High CPU temperature
• zpool health

New checks are welcome!

Principles

• Simple: Easy to set up, easy to use, easy to modify
• Portable: Keep dependencies to a minimum

Dependencies

• bourne-compatible shell
• curl
• Base components like bc, grep, awk, top

Installation

It can be run from its own directory, or it can be installed system-wide under a PREFIX like /usr/local. The main script is in ./bin, the common functions and scouts live in ./libexec/hermodr/. There's a sample hermodr.conf.sample in ./etc that needs to be copied to hermodr.conf.

Running

Run it in a crontab as often as you wish, e.g. 0 * * * * /bin/hermodr It does not need root privileges to run.

Portability

It is supposed to work on:

• All BSDs
• SunOS
• Linux