downtimed is a program that monitors operating system downtime, uptime, shutdowns, and crashes and records such events. At OS startup it logs information about previous downtime. It then periodically updates a time stamp file on the disk, which is used to determine the approximate time when the system was last up and running. During a graceful system shutdown, it records a time stamp in another file. The downtimes(1) command line tool can be used to inspect records of past downtime.
Jmx4Perl provides an alternate way of accessing Java JEE Server management interfaces that are based on JMX (Java Management Extensions). It is an agent-based approach where a small Web application deployed on the application server provides HTTP/JSON-based access to JMX MBeans registered within the application server. It is set up from a handful of Perl modules, which can be integrated seamlessly in your own programs. It also includes a Nagios plugin, check_jmx4perl, a jmx4perl command line tool for remote JMX queries and operations, and a readline-based JMX shell j4psh, with context sensitive command completion and syntax highlighting.
The XE Toolkit is a multi-platform, network-aware, secure performance monitoring solution for tactical analysis of enterprise computing systems. It uses Java and provides an API in the form of Java jar files that contain the programmatic interfaces needed to craft custom tools. It remains a toolkit, perhaps more complex than the SE Toolkit, but also far more versatile.
Yet Another Flowmeter (YAF) is a tool for network flow capture, primarily designed to operate efficiently on white box hardware and generate IPFIX flow records. It is designed to operate primarily on Unix-based systems (including Mac OS X), and is supported by the Network Situational Awareness team at CERT.
RHQ is a management platform for everything from the OS level load and network metrics through common databases to application servers and projects. The system includes support for monitoring and/or managing Apache httpd, Apache Tomcat, JBoss Application Server, PostgreSQL, and other popular open source projects. It is built on the powerful RHQ plugin model that allows for the quick development of support for new projects. It supports inventory auto-discovery, rich monitoring and alerting, operational control, configuration management, content deployment, log tracking, and full history and auditing. It supports fine-grained security and rich group management.