Check_MK is a complex addon for Nagios/Icinga and consists of three subprojects. The check and inventory system Check_MK is a general purpose Nagios plugin for retrieving data. It adopts a new approach for collecting data and obsoletes NRPE, check_by_ssh, NSClient, and check_snmp. It features a significant reduction of CPU use on the Nagios host and automatic inventory of items to be checked, and is especially useful with larger Nagios installations. "MK Livestatus" gives immediate and fast access to live and historic Nagios status data. It's a supported backend for many addons including NagVis, NagiosBP, and Thruk. "Check_MK Multisite" is a feature complete replacement for the Nagios GUI, and uses MK Livestatus as a backend. It is very fast, and supports efficient distributed monitoring.
encsh is a simple tool that encrypts a shell or other interpreted script and puts a wrapper around it. The end result is an executable which, when given the correct password, will be decrypted and run through a pipe, effectively keeping the plain text of the script away from the disk.
Consh is a set of programs that can turn one or more UNIX hosts on a trusted LAN into a singular Bourne shell multi-computer on which shell scripts are run concurrently. The service abstracts hosts into what appears to be shell process with a fixed number of threads or workers, to which work may be assigned and results received concurrently. It includes utilities that assign commands to workers in parallel and a command that initiates distributed barriers between workers for synchronization purposes. Environment variables can be set on a per-host basis to implement locking mechanisms like semaphores or ticket algorithms. Daemons can delegate work to one another as needed.
The KornShell language is an interactive command language that provides access to the Unix system and to many other systems, on the many different computer systems on which it is implemented. The KornShell language is also a complete, powerful, high-level programming language for writing applications, often more easily and quickly than with other high-level languages. This makes it especially suitable for prototyping. There are two other widely used shells, the Bourne shell developed by Steven Bourne at AT&T Bell Laboratories, and the C shell developed by Bill Joy at the University of California. ksh has the best features of both, plus many new features of its own. Thus ksh can do much to enhance your productivity and the quality of your work, both in interacting with the system, and in programming. ksh programs are easier to write, and are more concise and readable than programs written in a lower level language such as C.