This is a feature which is currently only included in the Subscription Edition of Observium.
Observium's Groups system uses the same device and entity matching scheme as the Alerting system.
The Groups system allows you to group together devices and entities based on a set of rules to enable easier categorisation and to make accessing information easier.
The Groups system is also used within the Scheduled Maintenance system to allow scheduling of maintenances for entire groups of devices or other entity types.
The associations pane allows you to define an initial set of rules to match entities to your group. Multiple associations can be added later for more flexibility.
The format of both the device and entity association conditions are
value. The device association conditions match against device attributes like hostname, os, distribution, location and sysObjectID. The Entity association conditions likewise match against entity attributes like a port's ifDescr, ifAlias or ifSpeed, a processor's description or a BGP session's remote AS.
A reference to the attributes for each entity type can be found in the Entity Reference.
An example to match all "Processor" memory pools on all Cisco IOS devices would be
os equals ios
mempool_descr match *processor
To match all possible devices or entities, simply use an asterisk
After creating a checker you need to go back to the run "regenerate". This will rebuild the group table to include the newly associated entities.