Multiping - Get MultiPing Support. Network monitoring in 60 seconds. MultiPing provides a graphical view of network performance, monitors hundreds of targets, and sends automatic alerts..
Unimus - Unimus is a Network Automation and Configuration management (NCM) solution designed for fast deployment network-wide and ease of use. Unimus does not require learning any abstraction or templating languages, and does not require any coding skills.
SmokePing - Smokeping is a tool for measuring latency.
Oxidized - configuration backup software (IOS, JunOS) - silly attempt at rancid
Fping (open source) - fping is a program to send ICMP echo probes to network hosts, similar to ping, but much better performing when pinging multiple hosts.
RANCID - RANCID - Really Awesome New Cisco confIg Differ.