Configuring Checkmk

Your entry point to the configuration of Checkmk is the Setup menu, which you can open via the navigation bar:

In this menu you will find the tools with which you can set up and configure Checkmk. The menu is divided into topics. Below each topic you will find the menu items.

The following table gives an overview of the menus and in which part of the User Guide you will find more detailed information.

Once you have more experience in working with the Setup menu, you will have learned its icons by heart — especially if you have the icons in the mega menus displayed for each menu item, as you can set in the User menu.

Then, for quick access, we recommend the Setup shortcuts snap-in for the sidebar with its icons for each Setup menu item:

Checkmk initially saves all changes you make only in a temporary configuration environment, in which you manage hosts, services and settings, and which does not yet affect the currently-running monitoring. Only by 'activating the pending changes' will these be transferred to the production monitoring environment.

Changes in the configuration — e.g. the addition of a new host — therefore initially have no influence on the monitoring. Only through activation do all changes that have accumulated since the last activation become active as a ‘bundle’ at the same time.

This might seem a little cumbersome, but it does have the advantage that more complex changes can be prepared without haste in advance before being put into production. For example, after adding a new host, you might want to define thresholds or remove some services before ‘arming’ the whole thing.

Whenever you make a change to the monitoring configuration using the Setup menu, this change will at first be picked up and held as pending.

You can see the number of pending changes that have not been activated yet in the navigation bar, in the Changes menu, indicated by the number in the yellow circle. If you click this icon, you will see the details of these pending changes:

Clicking the Activate pending changes button applies the changes. After a short wait, you will receive a confirmation that the changes have been successfully activated and everything is up to date. The number in the Changes menu has disappeared and will remain so until the next change is pending.

The slideout shown above provides a summary of the most important information. This allows you to see at a glance whether there are any problems with activation or with sites. Such problems can prevent pending changes from being activated. In this case, it is advisable to get the full overview using the Activate pending changes view. You can open this page from the slideout by clicking the button showing the three numbers or on Open full view:

On this page, you can start activating the changes by clicking Activate on selected sites.

Whichever method you choose, when you activate the changes, a new configuration for the monitoring core is generated from the configuration files, and the monitoring core is instructed to use this configuration immediately:

This clears the list of pending changes. These entries are not lost however — they can subsequently be called up via Setup > General > Audit log. There you will find the contents of the log file with all activated changes that have ever been made in the site. The Audit log can be filtered and shows today’s changes by default.

You will encounter the activation of changes again and again when setting up your monitoring system, as well as every time you adjust the configuration later on. Especially if you make more complex modifications to your system, you may want to revert changes during the editing process instead of activating them. Use the menu item Changes > Revert changes for this purpose.

This allows you to discard all pending changes since the last Activate on selected sites:

All changes that will be reverted if you approve the confirmation dialog are displayed in the lower area. This takes you back to the status of the last change activation.