This document describes how you can monitor “private” services and attributes of GNU/Linux devices, such as:
- Memory usage
- CPU load
- Disk usage
- Running processes
- etc.
Several methods to monitor GNU/Linux devices are available:
- SNMP – Install or activate the linux SNMP agent and configure it to serve system statistics;
- Local Agent – Provides faster query interval, more flexibility, passive and active communication methods;
- SSH – Should only be executed for infrequent checks as these have a high impact on the client and server CPU. It’s also very slow to execute overall, and will not scale when polling thousands of devices;
- Monitoring Publicly Available Services – Public services provided by GNU/Linux devices (like HTTP, FTP, POP3, etc.) can be easily monitored.