Host Status Monitor App is a program that allows you to automatically monitor multiple Internet hosts for downtime. It runs from command line or GUI and can visually indicate host status or email you when a machine goes down. Configuration is performed through two files: a program configuration file (hoststatsmonitor.conf), and a list of hosts to be monitored (hostlist.txt).
pssh and shmux have some customization issues, like inflexible IPs/hostnames specification, simultaneously spawning threads for all hosts (pssh), which is a problem with many hosts, or having to download/upload files with a separate command. cssh.py was written to resolve such problems. It has a fixed (configurable) length queue of active SSH threads, the ability to specify IPs/hostnames in 3 ways, configurable username, password, and SSH port per host, simultaneous download and upload of files/directories (using a built-in SCP implementation), again with configurable queue length, the ability to upload and execute a script with one switch, and many other useful options, like additional saving cmd outputs in a separate file for each machine (-d output_dir), or suppressing printing out hosts for which a given command produced no output (-b).
Bcfg2 helps system administrators produce a consistent, reproducible, and verifiable description of their environment, and offers visualization and reporting tools to aid in day-to-day administrative tasks. It is based on an operational model in which the specification can be used to validate and optionally change the state of clients, but in a feature unique to bcfg2 the client's response to the specification can also be used to assess the completeness of the specification. Using this feature, bcfg2 provides an objective measure of how good a job an administrator has done in specifying the configuration of client systems. Bcfg2 is therefore built to help administrators construct an accurate, comprehensive specification. Bcfg2 has been designed from the ground up to support gentle reconciliation between the specification and current client states. It is designed to gracefully cope with manual system modifications. Bcfg2 can also enable the construction of complex change management and deployment strategies.
PostRemoteLog is a tool that allows you to send information across the network to a centralized location. Three methods are currently supported: XMLRPC, Email, and Growl. It is generally aimed at system administrators who want to keep track of information such as backup post-run scripts, network monitoring scripts, UPS information, service outages, power on/off, unexpected restarts, etc. PostRemoteLog is designed to be used in other scripts. Captured data can be analyzed and aggregated as needed.
UDP Test is a simple UDP server and client bundled into a single script. It is designed to be used as a network testing tool, and it detects packet loss and corruption. UDP is a lossy network transport in that UDP packets may be dropped if there is not enough capacity to send them. UDP is typically used in real-time scenarios such as voice and video chat. udptest.rb is designed to be as simple as possible. It bounces small packets from the client to the server and back again. If the packet checksum is incorrect at any point, the script exits with an error. This type of script is designed to detect faulty hardware and errors in configuration, as well as network performance.
Quota Check is a simple application which is designed to run when a user logs into a computer. If they have less than a certain amount of free disk quota, they are told to visit the system administrator and are logged out. When a user tries to log into a network home directory which has a quota enforced, and they don't have enough disk space, they risk corrupting their files. Quota Check makes this situation very clear to users who may be otherwise unaware of the problem.