# About Xymon

In this document:

- What is Xymon ?
- Where can I download Xymon ?
- Support
- Are there any other sites with Xymon stuff?
- Who are you ?

### What is Xymon ?

Xymon is a tool for monitoring servers, applications and networks. It collects information about the health of your computers, the applications running on them, and the network connectivity between them. All of this information is presented in a set of simple, intuitive webpages that are updated frequently to reflect changes in the status of your systems.

Xymon is capable of monitoring a vast set of network services, e.g. mail-servers, web-servers (both plain HTTP and encrypted HTTPS), local server application logs, ressource utilisation and much more.

Much of the information is processed and stored in RRD files, which then form the basis for providing trend graphs showing how e.g. webserver response-times vary over time.

Xymon was inspired by the Big Brother monitoring tool, a freely available tool from BB4 Technologies (now part of Quest Software) with some of the features that Xymon has. But Xymon is better than Big Brother in many ways:

- Xymon can handle monitoring lots of systems.

  Big Brother is implemented mostly as shell-scripts, and performance suffers badly from this. In large networks where you need to monitor hundreds or thousands of hosts, processing of the data simply cannot keep up. Another problem with BB is that it stores all status-information in individual files; when you have lots of hosts and statuses, the amount of disk I/O triggered by this severely limits how many systems you can monitor with one BB server.
  Xymon avoids these performance bottlenecks by keeping most of the ever-changing data in memory instead of on-disk, and by being implemented in C rather than shell scripts.

- Xymon has a centralized configuration.

  Xymon keeps all configuration data in one place: On the Xymon server. Big Brother has lots of configuration files stored on the individual servers being monitored, so to change a setting you may need to logon to several servers and change each of them individually.

- Xymon is easy to setup and deploy.

  Big Brother has a huge number of add-ons, available from the www.deadcat.net site. This is both a blessing and a curse - you can find anything you need as an add-on, but many of the add-ons really ought to have been part of the base package. E.g. the ability to track historical performance data, simple things such as monitoring SSL-enabled services and SSL certificates, or just something as simple as a GUI for temporarily disabling monitoring of a system. Maintaining and improving all of these add-ons gets really complex.
  Xymon has all of these features built-in so you don't have to worry about getting the right add-ons and maintaining them - they come with the base package.
  Also, when it comes to deploying the client-side packages, Xymon clients require no configuration changes when you install them on multiple hosts. So you can setup a template client installation, and then blindly copy it to all of your hosts.

- Xymon is actively being developed.

  New Xymon versions appear regularly, usually every 4-6 months. In contrast, development of Big Brother appears to have stopped - at least when it comes to the non-commercial (BTF) version.

- Xymon is licensed as Open Source - Big Brother is not.

  Although the BB "Better-than-Free" license permits the use of BB for non-commercial use without having to buy a license, it is still a non-free package in the Open Source sense. I fully respect the decision of the people behind Big Brother to choose the licensing terms they find best - just as I can choose the licensing terms that I find best for the software I develop. It is my sincere belief that an Open Source license works best for a project such as Xymon, where community involvement is essential to get a tool capable of monitoring as many different systems as possible.

  An interesting essay appeared recently, which tries to explain why Open Source is the natural way for a software product to evolve. If you are curious as to why the trend seems to be that more and more software exist in an Open Source version, I suggest you have a look at it.

### Didn't you write something called "bbgen" and "Hobbit" ?

Yes I did. The bbgen toolkit was the name I used for Xymon from 2002 until the end of 2004 (i.e. bbgen version 1.x, 2.x and 3.x). The bbgen versions relied on a Big Brother server to hold the monitoring data and status logs, and this turned out to be a real performance problem for me. So I needed to completely replace Big Brother with something more powerful. In March 2005 version 4 was ready and capable of operating without any need for a Big Brother server, so I decided to change the name to avoid any misunderstanding about whether this was an add-on to Big Brother, or a replacement for it. Xymon no longer has any relation to Big Brother.

From 2005 until November 2008 the project was called "Hobbit". However, it turned out that this is a trademarked name, and I was asked to stop using it. Therefore the project is now called Xymon.

### Why did you call it Xymon ?

During the late summer and autumn of 2008 several new names for the project were discussed on the mailing list. I was looking for a name that was short, easy to pronounce, free of any legal ties, and a suitable group of domain names should be available. "Xymon" fit all of these criteria, and just sounded right to me - "XY" could be seen as meaning "anything" and "mon" is short for "monitor". So "Xymon" really just means "The Anything Monitor".

### Why should I use Xymon ? My Big Brother setup works just fine.

It is your choice. I think Xymon has many improvements over BB, so I would of course say 'Yes, I think you should'. But in the end it is You who have to deal with the hassle of setting up and learning a new system, so if you are comfortable with what Big Brother is doing for you now, I am not forcing you to switch. If you want to see what some of the Xymon users think about changing to Xymon, check out this thread (continued here) from the Xymon mailing list archive. The executive summary of those messages is that You won't regret switching.

### So where can I download Xymon?

The Xymon sources are available on the project page at Sourceforge.

### Support

There are two mailing lists about Xymon:

- The hobbit@hswn.dk mailing list is for general discussion about Xymon. To avoid spam you must be a subscriber to the list before you are allowed to post mesages. To subscribe to the list, send an e-mail to hobbit-subscribe@hswn.dk.
  There is an archive of the list.
- The hobbit-announce list is an announcement-list where new versions of Xymon will be announced. You can subscribe to the list by sending an e-mail to hobbit-announce-subscribe@hswn.dk.

If you have a specific problem with something that is not working, first check the list of known issues, and try to search the list archive. If you don't find the answer, post a message to the Xymon mailing list - I try to answer questions about Xymon in that forum.

### Are there any other sites with Xymon stuff?

Several projects have sprung up around Xymon:

- BBWin is a client for Microsoft Windows systems. It is available from the BBWin project page at Sourceforge.
- DevMon is a tool to collect data from SNMP-capable devices. It is available from the DevMon project page at SourceForge.
- The Shire is a repository of Xymon add-on scripts, utilities, sample configurations etc. which is currently being established. At the time of writing (August 2006) this is just being started, but you can check out The Shire project page at SourceForge.
- The Xymon Wiki has some information about Xymon usage.
- Deadcat is a repository for Big Brother extensions. Although these were written for Big Brother, most of these can be used with Xymon with little or no extra work since Xymon is compatible with the Big Brother extensions. See the Deadcat site.

### Who are you ?

My name is Henrik Storner. I was born in 1964, and live in Copenhagen, the capital of Denmark which is a small country in the northern part of Europe. I have a M.Sc. in Computer Science from the University of Copenhagen, and have been working with computers and Unix systems professionally since 1984. I have been developing bits and pieces of Open Source software for the past 10 years - you'll find my name in the Linux kernel CREDITS file - and I am actively involved in the local Linux Users Group SSLUG, one of the largest LUG's world-wide, where I am a systems administrator for their Internet servers (web, e-mail, news).

I started using Big Brother around 1998, for monitoring a bunch of servers that I was administering. In late 2001 I began working for the CSC Managed Web Services division in Copenhagen, and one of my first tasks was to improve on the monitoring and SLA reporting. After looking at what the standard tools could do, I decided to setup a Big Brother system as a demonstration of what could be done. This was an immediate success. Systems were rapidly added to the Big Brother monitor, and I began to see some of the scalability problems that happen when you go from monitoring 50 servers to monitoring 500 (not to mention the 2500 hosts we are currently - 2006 - keeping tabs on). So I decided it was time to do something about it, and during the autumn and early winter 2002 bbgen was born. The rest is history.