I'm not sure what the default health check interval is.
From the userguide:
OnGuard Health Check Interval (in hours): Specify the number of hours that OnGuard will skip health checks for healthy clients.
NOTE: Note the following information when you set the OnGuard Health Check Interval parameter:
| | You can set this parameter if OnGuard mode is set to health only. |
| | This parameter is valid only for wired and wireless interface types. |
| | This parameter is not applicable for the OnGuard Dissolvable Agent, VPN, and Other interface types. |
You can also specify the health check interval in the Agent enforcement (Configuration > Agent enforcement > New attribute) profile to create different Agent Enforcement Profiles for different users
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Keep-alive Interval (in seconds): Specify a keep-alive interval for OnGuard agents.
The connected OnGuard Agents periodically send heart-beat (Keep-Alive) messages to ClearPass Policy Manager. This interval is defined by the Keep-alive Interval (in seconds) parameter. The default value is 60 seconds.
ClearPass uses Keep-Alive messages to:
| | Update the status of OnGuard Agents regarding OnGuard Activity. |
| | Issue CoA (Change of Authorization) for a Session Restrictions Enforcement Profile if OnGuard Agent is disconnected: |
| | Session-Check > Agent-Connection = Down |
| | Post-Auth-Check > Action = Disconnect |
For related information, see Session Restrictions Enforcement Profile.