Set Folders and Host Attributes

These rules control how hosts are exported to Checkmk: which folder they land in, which attributes they carry, and special behaviors like cluster creation or opt-outs.

Go to: Modules → Checkmk → Set Folder and Attributes of Host

Folder-based rules stack automatically. All folder outcomes across all matching rules are combined in sort order to produce a nested folder path like /this/is/my/folder. Use the Last Match option on rules to stop evaluation after the first match and avoid unexpected stacking.

Available Actions

Action	Description
Move to Folder	Move the host to a folder. Supports full Jinja — variables that do not match cause the rule to be skipped.
Folder by Attribute Name	Use the attribute key as the folder name, selected by attribute value.
Pool Folder	Assign host to a Folder Pool. Optionally restrict to specific pool names (comma-separated). See Folder Pools.
CMK Attribute by Syncer Attribute	Export a Syncer attribute to Checkmk under the same or a mapped attribute name.
Custom CMK Attributes	Create a key:value attribute. Use {{HOSTNAME}} as placeholder. Separate multiple values with \|\|.
Remove given Attribute if not assigned	Remove specified Checkmk attributes if no other Syncer rule sets them for this host.
Cluster	Create the host as a Cluster. Specify which attributes contain the node names (comma-separated, wildcard * supported).
Parents	Set the host parent. Jinja supported.
Move Optout	Host is never moved to another folder after initial creation.
Update Optout	Host attributes are never updated after initial creation.
Create Optout	Host is not created in Checkmk, but its attributes are updated if it already exists.
Prefix Labels	Every exported label gets the configured prefix.
Update only Prefixed Labels	Only labels with the given prefix are changed by the Syncer.
Dont update prefixed Labels	Labels with the given prefix are never touched by the Syncer.

Write Status Back (CMK_WRITE_STATUS_BACK)

When CMK_WRITE_STATUS_BACK is enabled in local_config.py, the Syncer writes the Checkmk existence status of each host back into the Syncer host inventory after every export run:

'CMK_WRITE_STATUS_BACK': True

For every host processed during a sync, the Syncer sets the inventory key checkmk_status:

Attribute	Type	Description
is_existing	boolean	True if the host exists in Checkmk, False if not

Access this value in conditions and Jinja templates as cmk__is_existing.

Custom Folder Attributes

The Syncer creates all required folders automatically. You can set Checkmk folder attributes — including the visible title — by appending them after a pipe character in the folder name.

Hardcoded folder with attributes:

/my_folder | {'title': 'My Nice Title', 'tag_something': 'value'}

Jinja-based folder name with attributes:

/{{my_jinja_var}} | {'title': 'My Nice Title', 'tag_something': 'value'}

Jinja in the attributes as well:

/{{my_jinja_var}} | {'title': '{{var_containing_title}}', 'tag_something': 'value'}

The pipe syntax is separate from the Jinja syntax — note where the pipe is placed relative to the closing }}.