Xymon is Open Source software, licensed under the GNU GPL. This means that you are free to use Xymon as much as you like, and you are free to re-distribute it and change it to suit your specific needs. However, if you change it then you must make your changes available to others on the same terms that you received Xymon originally. See the file COPYING in the Xymon source-archive for details.
Xymon was called "Hobbit" until November 2008, when it was renamed to Xymon. This was done because the name "Hobbit" is trademarked.
Xymon initially began life as an enhancement to Big Brother called "bbgen". Over a period of 5 years, Xymon has evolved from a small add-on to a full-fledged monitoring system with capabilities far exceeding what was in the original Big Brother package. Xymon does still maintain some compatibility with Big Brother, so it is possible to migrate from Big Brother to Xymon without too much trouble.
Migrating to Xymon will give you a significant performance boost, and provide you with much more advanced monitoring. The Xymon tools are designed for installations that need to monitor a large number of hosts, with very little overhead on the monitoring server. Monitoring of thousands of hosts with a single Xymon server is possible - it was developed to handle just this task.
It is recommended that you setup a dedicated account for Xymon.
Communications between the Xymon server and Xymon clients use the Big Brother TCP port 1984. If the Xymon server is located behind a firewall, it must allow for inbound connections to the Xymon server on tcp port 1984. Normally, Xymon clients - i.e. the servers you are monitoring - must be permitted to connect to the Xymon server on this port. However, if that is not possible due to firewall policies, then Xymon includes the xymonfetch(8) and msgcache(8) tools to allows for a pull-style way of collecting data, where it is the Xymon server that initiates connections to the clients.
The Xymon web pages are dynamically generated through CGI programs.
Access to the Xymon web pages is controlled through your web server access controls, e.g. you can require a login through some form of HTTP authentication.
RRDtool This library is used to store and present trend-data. It is required.
libpcre This library is used for advanced pattern-matching of text strings in configuration files. This library is required.
OpenSSL This library is used for communication with SSL-enabled network services. Although optional, it is recommended that you install this for Xymon since many network tests do use SSL.
OpenLDAP This library is used for testing LDAP servers. Use of this is optional.
For more detailed information about Xymon system requirements and how to install Xymon, refer to the on-line documentation "Installing Xymon" available from the Xymon web server (via the "Help" menu), or from the "docs/install.html" file in the Xymon source archive.
An archive of the mailing list is available at http://lists.xymon.com/archive/
If you just want to be notified of new releases of Xymon, please subscribe to the xymon-announce mailing list. This is a moderated list, used only for announcing new Xymon releases. To be added to the list, send an e-mail to email@example.com or visit http://lists.xymon.com/mailman/listinfo/xymon-announce .
xymond(8) is the core daemon that collects all reports about the status of your hosts. It uses a number of helper modules to implement certain tasks such as updating log files and sending out alerts: xymond_client, xymond_history, xymond_alert and xymond_rrd. There is also a xymond_filestore module for compatibility with Big Brother.
xymond_channel(8) Implements the communication between the Xymon daemon and the other Xymon server modules.
xymond_history(8) Stores historical data about the things that Xymon monitors.
xymond_rrd(8) Stores trend data, which is used to generate graphs of the data monitored by Xymon.
xymond_alert(8) handles alerts. When a status changes to a critical state, this module decides if an alert should be sent out, and to whom.
xymond_client(8) handles data collected by the Xymon clients, analyzes the data and feeds back several status updates to Xymon to build the view of the client status.
xymond_hostdata(8) stores historical client data when something breaks. E.g. when a web page stops responding xymond_hostdata will save the latest client data, so that you can use this to view a snapshot of how the system state was just prior to it failing.
xymonping(1) performs network connectivity (ping) tests.
xymonnet(1) runs the network service tests.
xymonnet-again.sh(1) is an extension script for re-doing failed network tests with a higher frequency than the normal network tests. This allows Xymon to pick up the recovery of a network service as soon as it happens, resulting in less downtime being recorded.
xymongen(1) takes care of updating the Xymon web pages.
svcstatus.cgi(1) This CGI program generates an HTML view of a single status log. It is used to present the Xymon status-logs.
showgraph.cgi(1) This CGI program generates graphs of the trend-data collected by Xymon.
hostgraphs.cgi(1) When you want to combine multiple graphs into one, this CGI lets you combine graphs so you can e.g. compare the load on all of the nodes in your server farm.
criticalview.cgi(1) Generates the Critical Systems view, based on the currently critical systems and the configuration of what systems and services you want to monitor when.
history.cgi(1) This CGI program generates a web page with the most recent history of a particular host+service combination.
eventlog.cgi(1) This CGI lets you view a log of events that have happened over a period of time, for a single host or test, or for multiple systems.
ack.cgi(1) This CGI program allows a user to acknowledge an alert he received from Xymon about a host that is in a critical state. Acknowledging an alert serves two purposes: First, it stops more alerts from being sent so the technicians are not bothered wit more alerts, and secondly it provides feedback to those looking at the Xymon web pages that the problem is being handled.
xymon-mailack(8) is a tool for processing acknowledgments sent via e-mail, e.g. as a response to an e-mail alert.
enadis.cgi(8) is a CGI program to disable or re-enable hosts or individual tests. When disabling a host or test, you stop alarms from being sent and also any outages do not affect the SLA calculations. So this tool is useful when systems are being brought down for maintenance.
findhost.cgi(1) is a CGI program that finds a given host in the Xymon web pages. As your Xymon installation grows, it can become difficult to remember exactly which page a host is on; this CGI script lets you find hosts easily.
report.cgi(1) This CGI program triggers the generation of Xymon availability reports, using xymongen(1) as the reporting back-end engine.
reportlog.cgi(1) This CGI program generates the detailed availability report for a particular host+service combination.
snapshot.cgi(1) is a CGI program to build the Xymon web pages in a "snapshot" mode, showing the look of the web pages at a particular point in time. It uses xymongen(1) as the back-end engine.
statusreport.cgi(1) is a CGI program reporting test results for a single status but for several hosts. It is used to e.g. see which SSL certificates are about to expire, across all of the Xymon web pages.
csvinfo.cgi(1) is a CGI program to present information about a host. The information is pulled from a CSV (Comma Separated Values) file, which is easily exported from any spreadsheet or database program.
clientupdate(1) Is used on Xymon clients, to automatically update the client software with new versions. Through this tool, updates of the client software can happen without an administrator having to logon to the server.
msgcache(8) This tool acts as a mini Xymon server to the client. It stores client data internally, so that the xymonfetch(8) utility can pick it up later and send it to the Xymon server. It is typically used on hosts that cannot contact the Xymon server directly due to network- or firewall-restrictions.
xymonproxy(8) is a proxy-server that forwards Xymon messages between clients and the Xymon server. The clients must be able to talk to the proxy, and the proxy must be able to talk to the Xymon server.
xymonfetch(8) is used when the client is not able to make outbound connections to neither xymonproxy nor the Xymon server (typically, for clients located in a DMZ network zone). Together with the msgcache(8) utility running on the client, the Xymon server can contact the clients and pick up their data.
xymon(1) is the tool used to communicate with the Xymon server. It is used to send status reports to the Xymon server, through the custom Xymon/BB protocol, or via HTTP. It can be used to query the state of tests on the central Xymon server and retrieve Xymon configuration files. The server-side script xymoncgimsg.cgi(1) used to receive messages sent via HTTP is also included.
xymoncmd(1) is a wrapper for the other Xymon tools which sets up all of the environment variables used by Xymon tools.
xymongrep(1) is a utility for use by Xymon extension scripts. It allows an extension script to easily pick out the hosts that are relevant to a script, so it need not parse a huge hosts.cfg file with lots of unwanted test-specifications.
xymoncfg(1) is a utility to dump the full hosts.cfg(5) file following any "include" statements.
xymondigest(1) is a utility to compute message digest values for use in content checks that use digests.
combostatus(1) is an extension script for the Xymon server, allowing you to build complicated tests from simpler Xymon test results. E.g. you can define a test that uses the results from testing your web server, database server and router to have a single test showing the availability of your enterprise web application.
trimhistory(8) is a tool to trim the Xymon history logs. It will remove all log entries and optionally also the individual status-logs for events that happened before a given time.
Version 2 of bbgen was released in April 2003, and added a tool for performing network tests.
Version 3 of bbgen was released in September 2004, and eliminated the use of several external libraries for network tests, resulting in a significant performance improvement.
With version 4.0 released on March 30 2005, the project was de-coupled from Big Brother, and the name changed to Hobbit. This version was the first full implementation of the Hobbit server, but it still used the data collected by Big Brother clients for monitoring host metrics.
Version 4.1 was released in July 2005 included a simple client for Unix. Log file monitoring was not implemented.
Version 4.2 was released in July 2006, and includes a fully functional client for Unix.
Version 4.3 was released in November 2010, and implemented the renaming of the project to Xymon. This name was already introduced in 2008 with a patch version of 4.2, but with version 4.3.0 this change of names was fully implemented.
Parts of the Xymon sources are from public-domain or other freely available sources. These are the the Red-Black tree implementation, and the MD5-, SHA1- and RIPEMD160-implementations. Details of the license for these is in the README file included with the Xymon sources. All other files are released under the GNU General Public License version 2, with the additional exemption that compiling, linking, and/or using OpenSSL is allowed. See the file COPYING for details.