On 2015-05-07 we have changed the way Check_MK is packaged and made available to you for download. Details can be found here. Please also note our article about the version numbers of Check_MK.
Check_MK Raw Edition (CRE)
The Check_MK Raw Edition is a full-blown IT monitoring solution - available under the terms of the GNU GPL version 2 and a couple of other open source licenses. You can you use, modify and pass along the CRE for free as long as you comply with these licenses.
Check_MK Enterprise Edition (CEE)
The Check_MK Enterprise Edition is based on the Raw Edition but contains many additional enterprise-class features and also entitles you to get professional manufacturer support. In order to download it you need a valid subscription.
You also can deploy the CEE by using or hardware or software appliance.
Enterprise Edition - Demo Version
If you like to try out the Check_MK Enterprise Edition without having a subscription, you can use these demo packages.
The Monitoring Agents can be found in your Check_MK installation on the page Monitoring Agents in WATO.
If you are looking for older versions, you will find them in the Download Archive. If you like to download the source code of Check_MK, you can download it here.