There are 2 possible options to automatically assign a Group after selecting an Area.
Install the NX_AUTOASG_GROUP_ONLY option through command window:
1) Open the command prompt on any CA SDM server
2) Run the following command:
pdm_options_mgr -c -s AUTOASG_GROUP_ONLY -v 1 -a pdm_option.inst
NOTE: run the command again adding the -t option to the end to save the changes permanently in NX.env.tpl
3) Open the NX.env file in the CA SDM installation folder and search for the variable @NX_AUTOASG_GROUP_ONLY=1. Typically, the variable is found at the end of the file.
4) Restart the CA SDM Daemon Server service. CA SDM auto assigns the tickets to the group only.
To assign a group based on the Area selected when creating the incident:
1) Install Area Defaults: Go to Administration tab > Options Manager > Request Mgr > Edit > Install > Save > Verify Area_Defaults is installed. Further information about Area_Defaults here: https://wiki.ca.com/display/CASM1401/Options+Manager#OptionsManager-RequestMgrOptions
2) Define a default group for the Area you want to automatically assign a group: Go to Administration tab > Service Desk > Requests/Incidents/Problems > Areas > Click on Area > Edit > Select the Group you want to assign based on the area.
3) Restart the CA SDM Servers.
NOTE: you should restart the SDM services as per your current installation - AA or Conventional.
Refer to the following documents for further details:
How to Assign Tickets to a Group and Not to Contacts within the Group
How to Restart the CA SDM servers