dstat is a versatile replacement for vmstat, iostat, netstat, nfsstat, and ifstat. It includes various counters (in separate plugins) and allows you to select and view all of your system resources instantly; you can, for example, compare disk usage in combination with interrupts from your IDE controller, or compare the network bandwidth numbers directly with the disk throughput (in the same interval).
Nagstamon is a Nagios status monitor with a UI that resides in the systray or as a floating statusbar on your desktop. It informs you in realtime about the status of your Nagios, Icinga, Opsview, Ninja, Check_MK/Multisite, Centreon, or Thruk-monitored network. It alerts you with sound and visual notification. Failed hosts and services are easy to connect with by SSH, RDP, and VNC. Custom actions can be run on certain events. It works best with GNOME, but also with KDE, Mac OS X, and Windows.
apache-top provides real-time display of the active processes from a remote apache server. It shows: the active apache processes with the associated PID, the status, the active seconds, the CPU usage, the associated VirtualHost, the accessing IP and the request (POST or GET, the file being accessed, and the used protocol); the server uptime and the time it was last restarted; CPU usage; requests per second, Kb per second, and the average Kb per request; the number of active and inactive processes; and a graph with the inactive and active processes and their status.
CaiCai is a network and services monitoring system. It performs tests for ping, DHCP, POP3, SMTP, FTP, etc. It does not require additional software installed on the remote side. It is fully configurable. It provides instant reports (via an HTML page), logs, statistics, and sound alarms.
SysScope is a graphing solution that facilitates the visual representation of RRDtool's Round Robin Databases (RRD). It retrieves the graph options from an Apache-style configuration file and, after making the necessary calls to rrdgraph, it generates static or dynamic HTML pages containing the graphs. The following backends are supported for the generation of the dynamic pages: CGI, FastCGI, mod_python, and WSGI.
Python Tracer lets you see your Python program's execution as a tree of function invocations, each tree node exposing the real time and CPU time (user/sys) of that call. The project consists of two main components: a Python tracer that can run your Python programs (much like "cProfile" and friends), and a GTK+ based GUI that can show the trace results. It uses a tiny auxiliary library (graphfile) to allow append-only writing and reading static DAGs directly from a file without reading it whole into memory at any stage.
Spike Asset Manager (SAM) is a cross-platform framework for probing a system for components and reporting them. It includes a driver file that probes for components commonly found in a LAMPJ stack (Apache, MySQL, PHP, Tomcat, etc). It can find multiple versions that are installed, query the RPM database, and indicate whether components are running.
Rugg is a hard drive and filesystem harness tool that allows you to test and benchmark drives and filesystems by writing simple to complex scenarios that can mimic the behaviour of real-world applications. Test scenarios can be implemented using Rugg's compact and versatile domain specific language.